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Soil resource availability impacts microbial response to organic carbon and inorganic nitrogen inputs

Journal of Environmental Sciences 2005年第5期17卷 705-710页

作者： ZHANG wei-jian w.zhu S.HU Department of Agronomy Nanjing Agricultural University Nanjing 210095 China Department of Plant Pathology North Carolina State University Raleigh NC 27605 USA Department of Biological Sciences State University of New YorkBinghamton Binghamton NY 13902 USA

Impacts of newly added organic carbon （C） and inorganic nitrogen （N） on the microbial utilization of soil organic matter are important in determining the future C balance of terrestrial ecosystems. we examined microbial responses to cellulose and ammonium nitrate additions in three soils with very different C and N availability. These soils included an organic soil（ 14.2% total organic C, with extremely high extractable N and low labile C）, a forest soi1（4.7% total organic C, with high labile C and extremely low extractable N）, and a grassland soil（1.6% total organic C, with low extractable N and labile C）. while cellulose addition alone significantly enhanced microbial respiration and biomass C and N in the organic and grassland soils, it accelerated only the microbial respiration in the highly-N limited forest soil. These results indicated that when N was not limited, C addition enhanced soil respiration by stimulating both microbial growth and their metabolic activity, New C inputs lead to elevated C release in all three soils, and the magnitude of the enhancement was higher in the organic and grassland soils than the forest soil. The addition of cellulose plus N to the forest and grassland soils initially increased the microbial biomass and respiration rates, but decreased the rates as time progressed. Compared to cellulose addition alone, cellulose plus N additions increased the total C-released in the grassland soil, but not in the forest soil. The enhancement of total C- released induced by C and N addition was less than 50% of the added-C in the forest soil after 96 d of incubation, in contrast to 87.5% and 89.0% in the organic and grassland soils. These results indicate that indigenous soil C and N availability substantially impacts the allocation of organic C for microbial biomass growth and/or respiration, potentially regulating the turnover rates of the new organic C inputs.

关键词： cellulose inorganic nitrogen microbial biomass microbial activity carbon sequestration

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ELECTROCHEMICAL INVESTIGATION ON CARBON NANOTUBE FILM wITH DIFFERENT PRETREATMENTS

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Acta Metallurgica Sinica(English Letters) 2003年第4期16卷 295-301页

作者： C.G.Hu w.L.wang w.zhu DepartmentofAppliedPhysics ChongqingUniversityChongaing400044China KeyLaboftheEducationMinistryforPhotoelectricTechnologyandSystem ChongqingUniversityChongqing400044China DepartmentofChemistry ChongqingUniversityChongqing400044ChinaManuscriptreceived25November2002

wide potential windows were found at carbon nanotube film electrodes in neutral solutions after being treated with nitric acid and mixed acid. Electrochemical reversibility was investigated at carbon nanotube films with different pretreatments for ferri/ferrocyanide and quinone /hydroquinone. Carbon nanotube film electrodes presented quasi-reversible electrochemical behavior for both electrolytes. In the range of scan rate, carbon nanotube film electrodes treated with acids showed heterogeneous electron-transfer properties, which was mainly controlled by its electron state density on the surface of the film. On the whole, the carbon nanotube electrode with nitric acid treatment presented the best electrochemical behaviors, so we chose it as an analytical electrode to determine the trace compound in dilute solution. The results demonstrated that this new electrode material exhibits superior performance characteristics for the detection of azide anion.

关键词： carbon nanotubes cyclic voltammetry treatment azide anion

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ELECTROANALYTICAL APPLICATIONS OF CARBOXYL-MODIFIED CARBON NANOTUBE FILM ELECTRODES

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Acta Metallurgica Sinica(English Letters) 2003年第4期16卷 289-294页

作者： C.G.Hu w.L.wang K.J.Liao w.zhu DepartmentofAppliedPhysics ChongqingUniversityChongqing400044China KeyLaboftheEducationMinistryforPhotoelectricTechnologyandSystem ChongqingUniversityChongqing400044China DepartmentofChemistry ChongqingUniversityChongqing400044ChinaManuscriptreceived25November2002

The electrochemical behavior of a carboxyl-modified carbon nanotube films was investigated to explore its possibility in electroanalytical applicaton. Cyclic voltammetry of quinone was conducted in 1mol/L Na2SO4, which showed a stable, quasi-reversible voltammetric response for quinone / hydroquinone, and the anodic and the cathodic peak potentials were 0.657V and -0.029V (vs. SCE) at a scan rate of 0.1V.s-1, respectively. Both anodic and cathodic peak currents depended linearly on the square root of the scan rate over the range of 0.01-0.5V.s-1, which suggested that the process of the electrode reactions was diffusion-controlled. Carboxyl-modified carbon nanotube electrodes made it possible to determine low level of dopamine selectively in the presence of a large excess of ascorbic acid in acidic media using derivative voltammetry. The results obtained were discussed in details. This work demonstrates the potential of carboxyl-modified carbon nanotube electrodes for electroanalytical applications.

关键词： carbon nanotube electrochemistry carboxyl modification dopamine

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帕金森病病人脑铁氧代谢的时空模式

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国际医学放射学杂志 2024年第4期 497-497页

作者： S.Yan J.Lu Y.Li J.Cho S.Zhang w.zhu 王笑男

摘要目的铁沉积和线粒体功能障碍与帕金森病（PD）的发生和发展密切相关。旨在提取深部灰质（DGM）的磁敏感值和氧摄取分数（OEF），探讨PD脑铁氧代谢的时空进展模

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Numerical Simulation of Temperature Distribution and ThermalStress Field in a Turbine Blade with Multilayer-Structure TBCs by a Fluid–Solid Coupling Method

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Journal of Materials Science & Technology 2016年第5期32卷 452-458页

作者： w.Z.Tang L.Yang w.zhu Y.C.Zhou J.w.Guo C.LU Key Laboratory of Key Film Materials and Application for Equipment(Hunan Province) School of Materials Science and EngineeringXiangtan UniversityXiangtan 411105China Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education School of Materials Science and EngineeringXiangtan UniversityXiangtan 411105China Hunan Provincial Key laboratory of Thin Film Materials and Devices School of Materials Science and EngineeringXiangtan UniversityXiangtan 411105China School of Mechanical Engineering Xiangtan University Xiangtan 411105China Department of Mechanical Engineering Curtin UniversityPerthWA 6845Australia

To study the temperature distribution and thermal-stress field in different service stages, a two-dimensional model of a turbine blade with thermal barrier coatings is developed, in which the conjugate heat transfer analysis and the decoupled thermal-stress calculation method are adopted. Based on the simulation results, it is found that a non-uniform distribution of temperature appears in different positions of the blade surface, which has directly impacted on stress field. The maximum temperature with a value of 1030 ℃ occurs at the leading edge. During the steady stage, the maximum stress of thermally grown oxide （TGO） appears in the middle of the suction side, reaching 3.75 GPa. At the end stage of cooling, the maximum compressive stress of TGO with a value of-3.5 GPa occurs at the leading edge. Thus, it can be predicted that during the steady stage the dangerous regions may locate at the suction side, while the leadine edge mav be more Drone to failure on cooling.

关键词： Thermal barrier coatings Temperature distribution Thermal-stress field Conjugate heat transfer Decoupled thermal-stress calculation Fluid–solid coupling

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Do specific ultrasonography features identified at the time of early pregnancy loss predict fetal chromosomal abnormality? e A systematic review and meta-analysis

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Genes & Diseases 2019年第2期6卷 129-137页

作者： J.Huang w.zhu J.Tang S.H.Saravelos L.C.Y.Poon T.C.Li Department of Obstetrics and Gynaecology The First Affiliated Hospital of Chongqing Medical UniversityChongqing400016China Department of Obstetrics and Gynaecology The Chinese University of Hong KongHong Kong SARChina IVF Unit Hammersmith HospitalImperial College Healthcare NHS TrustLondonUK

To investigate the association of specific ultrasonography features identified during the diagnosis of early pregnancy loss(EPL)and abnormal karyotype.This was a systematic review and meta-analysis conducted in accordance with PRISMA criteria.we searched PubMed,Cochrane and Ovid MEDLINE from 1977 to Jan 2017 to identify the articles that described EPL with karyotype and ultrasonography features.Risk differences were pooled to estimate the chromosomal abnormality rates in ultrasonography features,including pre-embryonic,enlarged yolk sac(YS),short crown rump length(CRL),small gestational sac(GS),symmetrical arrested growth embryo,or gestational sac with only a YS.Quality assessment of included studies was performed using Strengthening the Reporting of Observational Studies in Epidemiology(STROBE)checklists for Observational Studies(2007 version).Thirteen studies were included in the meta-analysis.Chromosomal abnormality was more likely to occur in embryonic EPL and enlarged YS.On the other hand,short CRL,small GS,symmetrical arrested growth embryo,or gestational sac with only a YS,were not associated with an increased risk of fetal chromosomal abnormality.Ultrasonography features at the time of diagnosis of EPL have limited predictive value of fetal chromosomal abnormality.

关键词： Ultrasonography Early pregnancy loss Chromosomal abnormality Predictive value

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SYNTHESIS OF CoFe_(2)O_(4)/Pb(Zr_(0.53)Ti_(0.47))O_(3)MULTIFERROIC COMPOSITE THICK FILMS BY LOw-SINTERING-TEMPERATURE SCREEN PRINTING METHOD

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Journal of Advanced Dielectrics 2011年第1期1卷 119-125页

作者： w.CHEN C.X.HUANG T.S.YAN w.zhu Z.P.LI X.F.CHEN O.K.TAN Microelectronics Center School of Electrical and Electronic Engineering Nanyang Technological University Singapore 639798 School of Materials and Science Engineering Nanyang Technological University Singapore 639798

CoFe_(2)O_(4)/Pb(Zr_(0.53)Ti_(0.47))TO_(3)(abbreviated as CFO/PZT)multiferroic composite thick films were successfully fabricated on alumina substrate with gold bottom electrode by screen printing method at a low-sintering temperature.The processing included the modi fication and dispersion of ferromagnetic CFO powder and ferroelectric PZT powder,the preparation of uniform pastes,and the selection of proper annealing temperature for composite thick films.Transmission electron microscopic pictures(TEM)indicated the submicron meter of particles size for both CFO and PZT particles.After annealing at 900℃ for 1 h in air,tape test con firmed the quality of multiferroic thick films as well as pure CFO and PZT films.X-ray diffraction(XRD)showed a coexistence of CFO and PZT phases;furthermore,a smooth surface was observed through scanning electron microscopic(SEM)pictures along with the sharp cross-sectional picture,indicative of 100m of film thickness.Ferromagnetic and ferroelectric properties were observed in CFO/PZT films simultaneously at room temperature.Compared with the reported CFO/PZT multiferrroic thin films,the present ferromagnetic property was closing to that of the chemical solgel synthesized film and even that from the physical pulsed laser deposition technique.However,the ferroelectric property showed a degenerated behavior,possible reasons for this was discussed and further optimization was also proposed for the potential multifunctional application.

关键词： Screen printing method composite thickfilms multiferroic properties

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Characterization of interface adhesion properties of the film-substrate system by compression-induced buckling method

Characterization of interface adhesion properties of the fil...

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第十二届全国物理力学学术会议

作者： w.zhu Y.-C.Zhou S.-G.Long Faculty of Materials Optoelectronics and PhysicsKey Laboratory of Low Dimensional Materials and Application Technology of Ministry of EducationXiangtan University

The compression-induced buckling method has been employed to evaluate the interface adhesion properties of electrodeposited nickel film on steel substrate.Based on the classic buckling theory,a thin film in compression bonded to a substrate is prone to interfacial delamination, interface adhesion parameters which related to energy release rate and loading phase angle are evaluated.In this paper,the estimated energy release rate and the loading phase angle increase with the compressive stress in film.The energy release rate is found to 34 J·m for the 60 urn film thickness and the loading phase angle varies from -57°to -65°with different compressive stress in film.According to the variation of loading phase angle,the ModeⅡfracture dominates the delamination growth

关键词： thin film buckling interface adhesion compression

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Determination of interfacial adhesion energies of thermal barrier coatings by compression test combined with a cohesive zone finite element model

Determination of interfacial adhesion energies of thermal ba...

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第十三届全国物理力学学术会议

作者： w.zhu L.Yang J.w.Guo Y.C.Zhou C.Lu Key Laboratory of Low Dimensional Materials & Application Technology Xiangtan UniversityMinistry of Education Faculty of Materials Optoelectronics and PhysicsXiangtan University School of Mechanical Engineering Xiangtan University Department of Mechanical Engineering Curtin University

Determination of interfacial adhesion energies of thermal barrier coatings(TBCs)is very important for understanding the failure mechanism and predicting the life of TBCs.Combined the compression test with cohesive zone finite element method,the interfacial adhesion energy is determined.It is found that the critical interfacial adhesion energy is 120 J/m2 and the corresponding loading phase angle is–56o.with the increases of half-length of crack,the crack propagation tends to steady-state,and the steady-state interface energy release rate reaches 150 J/m2,edge delamination experiences almost pure mode II.The results are good agreement with the FEM simulation results and the values available in the literatures determined by different test methods,which confirms validity of the method used in this study.

关键词： interfacial adhesion energy thermal barrier coatings compression tests edge delamination cohesive zone model

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颅内钙化和出血:定量磁敏感成像描述特征

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国际医学放射学杂志 2014年第2期 175-176页

作者： w.Chen w.zhu I.Kovanlikaya A.Kovanlikaya T.Liu S.wang 张倩 Department of Radiology Tongji HospitalTongji Medical College Huazhong University of Science& Technology

目的比较MR梯度回波(GRE)相位像和定量磁敏感成像(QSM)2种技术在探测颅内钙化和出血的能力。材料与方法本回顾性研究经当地伦理委员会批准。选取38例

关键词：磁敏感成像特异度颅内钙化

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