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Wind-diesel hybrid power system integration in the south Algeria

Khaireddine ALLALI,El Bahi AZZAG,Nabil KAHOUL

《能源前沿（英文）》 2015年 第9卷 第3期   页码 259-271 doi: 10.1007/s11708-015-0367-5

摘要： In most isolated sites situated in south Algeria, the diesel generators are the major source of electrical energy. Indeed, the power supply of these remote regions still poses order problems (technical, economical and ecological). The electricity produced with the help of diesel generators is very expensive and responsible for CO emission. These isolated sites have significant wind energy potential. Hence, the use of twinning wind-diesel is widely recommended, especially to reduce operating deficits. The objective of this paper is to study the global modeling of a hybrid system which compounds wind turbine generator, diesel generator and storage system. This model is based on the control strategy to optimize the functioning of the hybrid system and to consolidate the gains to provide proper management of energy sources (wind, diesel, battery) depending on the load curve of the proposed site. The management is controlled by a controller which ensures the opening/closing of different power switches according to meteorological conditions (wind speed, air mass, temperature, etc).

关键词： wind-diesel     storage system     isolated site     management     simulation    

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Significance of using isolated footing technique for residential construction on expansive soils

Harry FAR,Deacon FLINT

《结构与土木工程前沿（英文）》 2017年 第11卷 第1期   页码 123-129 doi: 10.1007/s11709-016-0372-8

摘要： Expansive soils cause problems with the founding of lightly loaded structures in many parts of the world. Foundation design for expansive soils is one of the most discussed and problematic issues in Australia as expansive soils were responsible for billions of dollars’ worth of damage to man-made structures such as buildings and roads. Several studies and reports indicate that one of the most common and least recognized problems causing severe structural damage to houses lies in expansive soils. In this study, a critical review has been carried out on the current Australian standards for building on expansive soils and they are compared with some techniques that are not included in the current Australian standards for residential slabs and footings. Based on the results of this review, the most effective and economical method has been proposed for construction of footings on all site classifications without restriction to 75mm of characteristic movement. In addition, it has become apparent that as design procedures for footings resting on sites with extreme characteristic movements are not included in the current Australian standards, there is a strong need for well-developed and simplified standard design procedures for characteristic soil movement of greater than 75mm to be included into the Australian Standards.

关键词： expansive soils     residential slabs     isolated footings     Australian Standards    

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Application of an efficient stochastic calculation method on the seismic analysis of an isolated structure

Wei GUO, Zhiwu YU

《结构与土木工程前沿（英文）》 2012年 第6卷 第4期   页码 379-384 doi: 10.1007/s11709-012-0180-8

摘要： An isolated structure often possesses distinct non-proportional damping characteristics. However, traditional seismic calculation theory and methods are derived based on the assumption that damping is proportional. Based on this drawback, a new, more efficient stochastic calculation method, an improvement on the pseudo-excitation method, is introduced. This method is then applied to the seismic analysis of an isolated structure. By comparing it with the forced decoupling, matrix inversion and iteration methods, it is shown that the presented method can produce accurate results while increasing the efficiency of the stochastic analysis. Moreover, the calculation process of the seismic response of an isolated structure is convergent. Based on the results of the example presented in this paper, the given method is applicable to the seismic analysis of an isolated structure and can be utilized in practice.

关键词： isolated structure     stochastic response     non-proportional damping     efficient     accurate     pseudo-excitation method    

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Influence of site conditions on seismic design parameters for foundations as determined via nonlinearsite response analysis

Muhammad Tariq A. CHAUDHARY

《结构与土木工程前沿（英文）》 2021年 第15卷 第1期   页码 275-303 doi: 10.1007/s11709-021-0685-0

摘要： Site conditions, including geotechnical properties and the geological setting, influence the near-surface response of strata subjected to seismic excitation. The geotechnical parameters required for the design of foundations include mass density ( ), damping ratio ( ), shear wave velocity ( ), and soil shear modulus ( ). The values of the last three parameters are sensitive to the level of nonlinear strain induced in the strata due to seismic ground motion. In this study, the effect of variations in soil properties, such as plasticity index ( ), effective stress ( ), over consolidation ratio (OCR), impedance contrast ratio ( ) between the bedrock and the overlying strata, and depth of soil strata over bedrock ( ), on seismic design parameters ( , , and ) was investigated for National Earthquake Hazards Reduction Program (NEHRP) site classes C and D, through 1D nonlinear seismic site response analysis. The Morris one-at-a-time (OAT) sensitivity analysis indicated that , , and were significantly influenced by variations in , while affected more than it affected and . However, the influence of on these parameters was less significant. It was also found that variations in soil properties influenced seismic design parameters in soil type D more significantly than in soil type C. Predictive relationships for , , and were derived based on the 1D seismic site response analysis and sensitivity analysis results. The , , and values obtained from the analysis were compared with the corresponding values in NEHRP to determine the similarities and differences between the two sets of values. The need to incorporate and in the metrics for determining , , and for the seismic design of foundations was highlighted.

关键词： site effects     1D seismic site response analysis     sensitivity analysis     foundations     shear wave velocity     soil shear modulus    

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Reactive power compensation of an isolated hybrid power system with load interaction using ANFIS tuned

Nitin SAXENA,Ashwani KUMAR

《能源前沿（英文）》 2014年 第8卷 第2期   页码 261-268 doi: 10.1007/s11708-014-0298-6

摘要： This paper presents an adaptive neuro fuzzy interference system (ANFIS) based approach to tune the parameters of the static synchronous compensator (STATCOM) with frequent disturbances in load model and power input of a wind-diesel based isolated hybrid power system (IHPS). In literature, proportional integral (PI) based controller constants are optimized for voltage stability in hybrid systems due to the interaction of load disturbances and input power disturbances. These conventional controlling techniques use the integral square error (ISE) criterion with an open loop load model. An ANFIS tuned constants of a STATCOM controller for controlling the reactive power requirement to stabilize the voltage variation is proposed in the paper. Moreover, the interaction between the load and the isolated power system is developed in terms of closed loop load interaction with the system. Furthermore, a comparison of transient responses of IHPS is also presented when the system has only the STATCOM and the static compensation requirement of the induction generator is fulfilled by the fixed capacitor, dynamic compensation requirement, meanwhile, is fulfilled by STATCOM. The model is tested for a 1% step increase in reactive power load demand at = 0 s and then a sudden change of 3% from the 1% at = 0.01 s for a 1% step increase in power input at variable wind speed model.

关键词： isolated wind-diesel power system     adaptive neuro fuzzy interference system (ANFIS)     integral square error (ISE) criterion     load interaction    

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Estimation of composite load model with aggregate induction motor dynamic load for an isolated hybrid

Nitin Kumar SAXENA,Ashwani Kumar SHARMA

《能源前沿（英文）》 2015年 第9卷 第4期   页码 472-485 doi: 10.1007/s11708-015-0373-7

摘要： It is well recognized that the voltage stability of a power system is affected by the load model and hence, to effectively analyze the reactive power compensation of an isolated hybrid wind-diesel based power system, the loads need to be considered along with the generators in a transient analysis. This paper gives a detailed mathematical modeling to compute the reactive power response with small voltage perturbation for composite load. The composite load is a combination of the static and dynamic load model. To develop this composite load model, the exponential load is used as a static load model and induction motors (IMs) are used as a dynamic load model. To analyze the dynamics of IM load, the fifth, third and first order model of IM are formulated and compared using differential equations solver in Matlab coding. Since the decentralized areas have many small consumers which may consist large numbers of IMs of small rating, it is not realistic to model either a single large rating unit or all small rating IMs together that are placed in the system. In place of using a single large rating IM, a group of motors are considered and then the aggregate model of IM is developed using the law of energy conservation. This aggregate model is used as a dynamic load model. For different simulation studies, especially in the area of voltage stability with reactive power compensation of an isolated hybrid power system, the transfer function of the composite load is required. The transfer function of the composite load is derived in this paper by successive derivation for the exponential model of static load and for the fifth and third order IM dynamic load model using state space model.

关键词： isolated hybrid power system (IHPS)     composite load model     static load     dynamic load     induction motor load model     aggregate load    

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Development and application of an off-site maintenance system in the petrochemical industry

Ruisheng YONG, Yanbing YE, Hanbin LUO, Lieyun DING

《工程管理前沿（英文）》 2017年 第4卷 第2期   页码 111-126 doi: 10.15302/J-FEM-2017027

摘要： On-site maintenance (ONSM) is critical to ensuring the safety of equipment in the petrochemical industry. However, many accidents occur during ONSM processes because of unstable equipment, complicated work environment, and human error. To reduce congestion and exposure to hazards during on-site operations and thereby reduce the probability of accidents, off-site maintenance (OFSM) is proposed based on Energy Release Theory (ERT). The information requirements for OFSM are analyzed. A support system for OFSM, which makes use of visualization, information management, and localization capabilities, is developed. A case study utilizing OFSM and its support system for an oil-loading facility of a petrochemical company is conducted. The application results indicated that implementation of OFSM system can significantly reduce the operation risks and can improve the operation efficiency.

关键词： on-site maintenance     petrochemical industry     safety     off-site maintenance system    

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Gene delivery into isolated

Nan Zheng, Ziyuan Song, Yang Liu, Lichen Yin, Jianjun Cheng

《化学科学与工程前沿（英文）》 2017年 第11卷 第4期   页码 521-528 doi: 10.1007/s11705-017-1612-8

摘要： The application of gene delivery materials has been mainly focused on mammalian cells while rarely extended to plant engineering. Cationic polymers and lipids have been widely utilized to efficiently deliver DNA and siRNA into mammalian cells. However, their application in plant cells is limited due to the different membrane structures and the presence of plant cell walls. In this study, we developed the cationic, -helical polypeptide that can effectively deliver DNA into both isolated protoplasts and intact leaves. The PPABLG was able to condense DNA to form nanocomplexes, and they exhibited significantly improved transfection efficiencies compared with commercial transfection reagent Lipofectamine 2000 and classical cell penetrating peptides such as poly(L-lysine), HIV-TAT, arginine9, and poly(L-arginine). This study therefore widens the utilities of helical polypeptide as a unique category of gene delivery materials, and may find their promising applications toward plant gene delivery.

关键词： α-helical polypeptide     plant gene delivery     protoplast     intact leaves     transfection    

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Macrozoobenthic assemblages in relation to environments of the Yangtze-isolated lakes

Baozhu PAN, Haijun WANG, Hongzhu WANG, Zhaoyin WANG

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 246-254 doi: 10.1007/s11783-011-0381-8

摘要： Eutrophication can shift lakes from a clear, macrophyte-dominated state to a turbid, algae-dominated state, and different habitat condition supports different fauna. Macrozoobenthos are good indicators of water environment, and studies on macrozoobenthic assemblage characteristics can help us to know which state a lake is in, thus provide the basis for its eutrophication control. In this study, a systematic investigation on macrozoobenthos was conducted in 17 Yangtze-isolated lakes to explore the macroecological laws of macrozoobenthic assemblages. Detrended correspondence analysis (DCA) revealed that variance of benthic assemblage structure occurred in two types of lakes. In macrophytic lakes, altogether 51?taxa of macrozoobenthos were identified. The average density and biomass of total macrozoobenthos were 2231?individuals·m and 1.69 g dry weight·m , respectively. Macrozoobenthic assemblage was characterized by dominance of scrapers (i.e. gastropods). In algal lakes, altogether 20 taxa of macrozoobenthos were identified. The average density and biomass of total macrozoobenthos were 2814 individuals·m and 1.38 g dry weight·m , respectively. Macrozoobenthic assemblage was characterized by dominance of collector-gatherers (i.e. oligochaetes). Wet biomass of submersed macrophytes ( ) and phytoplankton chlorophyll concentration ( ) were demonstrated as the key factor structuring macrozoobenthic assemblages in macrophytic and algal lakes, respectively.

关键词： macrozoobenthos     assemblage characteristics     environment analyses     macrophytic lake     algal lake    

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Bioproduction of D -psicose using permeabilized cells of newly isolated Rhodobacter sphaeroides SK011

Longtao ZHANG, Bo JIANG, Wanmeng MU, Tao ZHANG,

《化学科学与工程前沿（英文）》 2009年 第3卷 第4期   页码 393-398 doi: 10.1007/s11705-009-0252-z

摘要： -psicose exits in an extremely small amount in nature and is difficult to be chemically synthesized. Only three bacteria have been used in the biotransformation of -psicose from -fructose. In this paper, another bacterium which could convert -fructose to -psicose was isolated and identified as . The process parameters of -psicose production using permeabilized cells of SK011 were optimized, including the permeabilization procedure: 0.1% (w/v) CTAB, 10min, and reaction conditions: cell concentration, 30g dry cell wt/L; concentration of substrate, 50g/L; 40°C, pH 9.0; reaction time, 8 h. Under the optimized conditions, the permeabilized cells produced approximately 6.5g/L -psicose with a -psicose productivity of 0.82g·L·h. This is the first report of bioproduction of -psicose using permeabilized cells of .

关键词： reaction     permeabilized     substrate     bacterium     process    

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Study of the mechanics of progressive collapse of FPB isolated beam-pier substructures

Jingcai ZHANG; Yong DING; Xinchun GUAN

《结构与土木工程前沿（英文）》 2022年 第16卷 第6期   页码 718-728 doi: 10.1007/s11709-022-0815-3

摘要： The horizontal stiffness of the isolated layer is reduced substantially by a friction pendulum bearing (FPB) toprotectthe structure from potential damages caused by earthquakes. However, horizontal stiffness is essential to progressive collapse resistance of structures. This paper presents a simplified model to assess the progressive collapse response of beam-pier substructure isolated by FPB. Progressive collapse resistance by flexural action of the beam and additional resistance owing to the horizontal restraining force was achieved. The influences of the equivalent radius and friction coefficient of the FPB, the applied axial force on the FPB, and span-depth ratio of the beam on the additional resistance were investigated. Simulations were conducted to verify the proposed model. The results show that progressive collapse resistance provided by horizontal restraining can be reduced as large as 46% and 88% during compressive arching action (CAA) and catenary action (CA), respectively. The equivalent radius of the FPB shows limited effect on the progressive collapse response of FPB isolated structures, but friction coefficient and applied axial force, as well as depth ratio of the beam, show significant influences on the additional progressive collapse resistance capacity. Finite element method (FEM) results are in good agreement with the result obtained by the proposed method.

关键词： friction pendulum bearing     progressive collapse     horizontal stiffness     compressive arching action     catenary action    

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Development of rocking constraint device with vertical damping capacity for three-dimensional base-isolated

《结构与土木工程前沿（英文）》 2023年 第17卷 第3期   页码 350-367 doi: 10.1007/s11709-022-0923-0

摘要： A new rocking constraint device (RCD) is developed for three-dimensional (3D) base-isolated frame structures by connecting a custom-designed cylinder pair to provide vertical damping with replaceable damping components installed outside the cylinders when the superstructure undergoes translational motion, and rocking constraint capacity when the superstructure is susceptible to rocking. Theoretical formulas for calculating the damping and rocking constraint stiffness of the RCD are proposed. Two series of sinusoidal loading tests are conducted at different loading frequencies and amplitudes to verify the damping and rocking constraint performance of the RCD. The test results show that the cylinder without orifices on its piston can provide the desired damping with a replaceable damping component, and that the RCD can effectively suppress rocking. Although the vertical stiffness of an individual cylinder is affected by the location of the replaceable damping component and loading frequency, the average vertical stiffness of the two cylinders, which determines the rocking constraint stiffness of the RCD, is independent of the two factors. Comparisons of the test and theoretical results indicate that the errors of the proposed formulas for calculating the damping and rocking constraint stiffness of the RCD do not exceed 12.9% and 11.0%, respectively.

关键词： three-dimensional isolation     rocking behavior     rocking constraint device     replaceable damping component     sinusoidal test    

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An integrated approach to site-specific management zone delineation

Yuxin MIAO, David J. MULLA, Pierre C. ROBERT

《农业科学与工程前沿（英文）》 2018年 第5卷 第4期   页码 432-441 doi: 10.15302/J-FASE-2018230

摘要：

Dividing fields into a few relatively homogeneous management zones (MZ) is a practical and cost-effective approach to precision agriculture. There are three basic approaches to MZ delineation using soil and/or landscape properties, yield information, and both sources of information. The objective of this study is to propose an integrated approach to delineating site-specific MZ using relative elevation, organic matter, slope, electrical conductivity, yield spatial trend map, and yield temporal stability map (ROSE-YSTTS) and evaluate it against two other approaches using only soil and landscape information (ROSE) or clustering multiple year yield maps (CMYYM). The study was carried out on two no-till corn-soybean rotation fields in eastern Illinois, USA. Two years of nitrogen (N) rate experiments were conducted in Field B to evaluate the delineated MZs for site-specific N management. It was found that in general the ROSE approach was least effective in accounting for crop yield variability (8.0%–9.8%), while the CMYYM approach was least effective in accounting for soil and landscape (8.9%–38.1%), and soil nutrient and pH variability (9.4%–14.5%). The integrated ROSE-YSTTS approach was reasonably effective in accounting for the three sources of variability (38.6%–48.9%, 16.1%–17.3% and 13.2%–18.7% for soil and landscape, nutrient and pH, and yield variability, respectively), being either the best or second best approach. It was also found that the ROSE-YSTTS approach was effective in defining zones with high, medium and low economically optimum N rates. It is concluded that the integrated ROSE-YSTTS approach combining soil, landscape and yield spatial-temporal variability information can overcome the weaknesses of approaches using only soil, landscape or yield information, and is more robust for MZ delineation. It also has the potential for site-specific N management for improved economic returns. More studies are needed to further evaluate their appropriateness for precision N and crop management.

关键词： economically optimum nitrogen rate     fuzzy cluster analysis     precision nitrogen management     site-specific management     soil landscape property     yield map    

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Pluripotent stem cells exhibiting similar characteristics can be isolated from human fetal bone marrow

FANG Baijun, SONG Yongping, LIN Quande, ZHAO Chunhua, SHI Mingxia

《医学前沿（英文）》 2007年 第1卷 第2期   页码 185-191 doi: 10.1007/s11684-007-0035-1

摘要： Previously, we reported that a cell population derived from human fetal bone marrow (BM), termed here Flk1CD34 postembryonic pluripotent stem cells (PPSCs) that have the characteristics of mesenchymal stem cells (MSCs), could differentiate into ectodermal, endodermal and mesodermal cell types at the single cell level , and that these cells could also differentiate into the epithelium of liver, lung, gut, as well as the hematopoietic and endothelial lineages after transplantion into irradiated non-obese diabetic/severe combined immunodeficient (NOD/SCID) mice. In this study, we further isolated pluripotent stem cells from human fetal heart, liver, muscle, lung, derma, kidney, and fat and then analyzed the characteristics and function of these stem cells. It was found that the phenotype of the culture-expanded pluripotent stem cells from different fetal tissues was similar to BM-derived Flk1CD34 PPSCs, i.e. Flk1 and CD44 positive, GlyA, CD34, CD45, class I-HLA and HLA-DR negative. Morphologically, these cells were fibroblast-like and the doubling time was about 30 h. More importantly, culture-expanded pluripotent stem cells from all these fetal tissues were able to differentiate into cells with morphologic and phenotypic characteristics of adipocytes, osteocytes, neurons, glial cells and hepatocytes. These pluripotent stem cells with characteristics similar to fetal BM-derived Flk1CD34 PPSCs can be selected and cultured from tissues other than the BM. This phenomenon may help explain the stem cell plasticity found in multiple human tissues. In addition, as fetal BM-derived Flk1CD34 PPSCs, these pluripotent stem cells from different fetal tissues had the capacity for self-renewal and multi-lineage differentiation even after being expanded for more than 40 population doublings . Thus, they may be an ideal source of stem cells for treatment of inherited or degenerative diseases.

关键词： endothelial     phenomenon     ectodermal     Flk1CD34 postembryonic     irradiated non-obese    

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Large-scale synthesis of isolated Mn2O3 nanotube/fiber with ferric nitrate as catalyst

ZHANG Aifei, LIU Jiping, L? Guangshu

《化学科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 55-58 doi: 10.1007/s11705-007-0011-y

摘要： Isolated MnO nanotubes and nanofibers were prepared very easily at a large scale with the liquid-phase catalysis method. The MnO nanotubes had dimensions of 30 50 nm (exterior diameter) and 0.2 1.0 ?m (length), approximately. The O nanofibers had dimensions of 10 30 nm (diameter) and 0.4 2.0 ?m (length), approximately. Nano-O with different microstructures including nanotubes, nanofibers and nanoparticles could be selectively synthesized by controlling the contents and proportions of potassium permanganate and ferric nitrate. Ferric nitrate was an ideal catalyst for the preparation of O nanotube/fiber. When cobalt nitrate or nickel nitrate was used as catalyst, only amorphous nano-O was synthesized. X-ray diffraction (XRD) result shows that the O nanotube has a crystalline structure different from o-O, t-O, h-O and ?-O.

关键词： different     nickel     exterior diameter     nanotube     XRD    

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标题 作者 时间 类型 操作

Wind-diesel hybrid power system integration in the south Algeria

Khaireddine ALLALI,El Bahi AZZAG,Nabil KAHOUL

期刊论文

Significance of using isolated footing technique for residential construction on expansive soils

Harry FAR,Deacon FLINT

期刊论文

Application of an efficient stochastic calculation method on the seismic analysis of an isolated structure

Wei GUO, Zhiwu YU

期刊论文

Influence of site conditions on seismic design parameters for foundations as determined via nonlinearsite response analysis

Muhammad Tariq A. CHAUDHARY

期刊论文

Reactive power compensation of an isolated hybrid power system with load interaction using ANFIS tuned

Nitin SAXENA,Ashwani KUMAR

期刊论文

Estimation of composite load model with aggregate induction motor dynamic load for an isolated hybrid

Nitin Kumar SAXENA,Ashwani Kumar SHARMA

期刊论文

Development and application of an off-site maintenance system in the petrochemical industry

Ruisheng YONG, Yanbing YE, Hanbin LUO, Lieyun DING

期刊论文

Gene delivery into isolated

Nan Zheng, Ziyuan Song, Yang Liu, Lichen Yin, Jianjun Cheng

期刊论文

Macrozoobenthic assemblages in relation to environments of the Yangtze-isolated lakes

Baozhu PAN, Haijun WANG, Hongzhu WANG, Zhaoyin WANG

期刊论文

Bioproduction of D -psicose using permeabilized cells of newly isolated Rhodobacter sphaeroides SK011

Longtao ZHANG, Bo JIANG, Wanmeng MU, Tao ZHANG,

期刊论文

Study of the mechanics of progressive collapse of FPB isolated beam-pier substructures

Jingcai ZHANG; Yong DING; Xinchun GUAN

期刊论文

Development of rocking constraint device with vertical damping capacity for three-dimensional base-isolated

期刊论文

An integrated approach to site-specific management zone delineation

Yuxin MIAO, David J. MULLA, Pierre C. ROBERT

期刊论文

Pluripotent stem cells exhibiting similar characteristics can be isolated from human fetal bone marrow

FANG Baijun, SONG Yongping, LIN Quande, ZHAO Chunhua, SHI Mingxia

期刊论文

Large-scale synthesis of isolated Mn2O3 nanotube/fiber with ferric nitrate as catalyst

ZHANG Aifei, LIU Jiping, L? Guangshu

期刊论文