检索结果-南通市图书馆

Weatherability and heat resistance enhanced by interaction between AG25 and Mg/AI-LDH

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第6期43卷 2758-2768页

作者： Pei-Yao Yang Xiang-Cui Liu Yu-Chao Wang Huan-Ran Zheng Jin-Xian Wang Jia-Yi Zheng Meng-Jie Liu Dan-Ni Deng Yu Bai Ying-Bi Chen Tong Zhang Zhi-Ming Liu Yong-Peng Lei State Key Laboratory of Powder metallurgy Powder Metallurgy Research InstituteCentral South UniversityChangsha 410083China Research institute of Chemical Defense Beijing 102205China

Although inorganic pigments in common spectral tuning materials show good weatherability and heat resistance,the limited color choices,weak coloring power,poor dispersibility,and a possibility of toxicity limit their *** the basis of organic pigments which possess a wide range of colors,high coloring power,good transparency,and high safety,herein,the modified pigment and biomimetic coating with improved weatherability,especially ultraviolet(UV)resistance(from 2 to 6 days),was achieved by intercalating acid green 25(AG25)pigment into Mg/Al-layered double hydroxides(Mg/Al-LDH).Furthermore,the heat resistance of AG25 was also significantly ***,the spectral stability of pigments after heat treatment is superior with almost unchanged spectral profile and green reflection *** formation of strong N-H bonds and the S-M(Mg,Al)bonds between Mg/Al-LDH laminates and AG25 molecules contributes to the *** work shows potential for biomimetic leaf materials in respect of reflective spectra stability.

关键词： Layered double hydroxide Biomimetic Acid green 25 Interaction Weatherability Heat resistance

Microstructure characterization of NiFe_2O_4-NiO solid-solid diffusion couple

在线全文

学校读者我要写书评

暂无评论

Journal of central south University 2012年第9期19卷 2411-2415页

作者：时凯华周科朝张雷李志友 State Key Laboratory of Powder metallurgy(central south University) Powder metallurgy Research institute Central South University

The solid state interdiffusion between NiFe204 and NiO in nitrogen atmosphere was studied by means of diffusion couple technique. NiFe204/NiO diffusion couple with plane interfaces was made by clamping method and sintering at 1 300℃ for 10 h. Scanning electronic microscopy （SEM） and energy-dispersive X-ray spectrometry （EDS） were used to analyze the microstructure and phase composition of the diffusion couples. The results indicate that a porous layer of uniform thickness forms along the NiFe2O4/NiO bonding interface and exhibits a deep penetration in the NiFe2O4 due to the Kirkendall effect. Furthermore, SEM observations reveal that the needle-like nickel ferrite precipitates form in NiO near the interface and the formation mechanism of them are inferred to be diffusion type solid-state phase changes.

关键词： NiFe2O4 microstructure diffusion Kirkendall effect

Effects of low-intensity pulsed ultrasound stimulation on porous hydroxyapatite blocks for posterolateral fusion of lumbar spine in rabbits

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2010年第10期20卷 1921-1927页

作者：卓祥龙吕红斌徐大启刘彬王锡阳张莹胡建中 Department of Spinal Surgery Xiangya HospitalCentral South University Orthopedic institute of central south University Department of Sports Medicine Xiangya HospitalCentral South University Research Center of Sports Medicine Central South University State Key Laboratory of Powder metallurgy Central South University

he effects of porous hydroxyapatite blocks（PHABs） and an adjunct low-intensity pulsed ultrasound stimulation（LIPUS） on the fusion rate in a rabbit spinal posterolateral fusion（PLF） model were *** rabbits underwent PLF with autograft and PHABs were randomly assigned to two groups：treated group with 20 min LIPUS daily and untreated control group for 4 weeks until *** fused motion segments were subjected to manual palpation,gross observation,and radiographic investigation before histomorphologic and scanning electron microscopic *** differences between the LIPUS group and the control group are found in the fusion rate,bone density gray scale,trabecular bone formation,osteoblast-like cells,chondrocytes and positive expression of BMP-2 and TGF-β1 in the junction zone（significance level p〈0.05）.The results suggest that LIPUS can increase fusion rates and accelerate bone in-growth into ***,PHAB and LIPUS may be used together to increase fusion rates in a rabbit spinal fusion model with a promising extension to human application.

关键词： low-intensity pulsed ultrasound stimulation lumbar posterolateral fusion porous hydroxyapatite blocks

Preheating-assisted solid-state friction stir repair of Al-Mg-Si alloy plate at different rotational speeds

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,metallurgy and Materials 2024年第4期31卷 725-736页

作者： Hui Wang Yidi Li Ming Zhang Wei Gong Ruilin Lai Yunping Li State Key Laboratory of Powder metallurgy Central South UniversityChangsha 410083China Research institute of Light Alloy Central South UniversityChangsha 410083China

Additive friction stir deposition(AFSD)is a novel structural repair and manufacturing technology has become a research hotspot at home and abroad in the past five *** this work,the microstructural evolution and mechanical performance of the Al-Mg-Si alloy plate repaired by the preheating-assisted AFSD process were *** evaluate the tool rotation speed and substrate preheating for repair quality,the AFSD technique was used to additively repair 5 mm depth blind holes on 6061 aluminum alloy *** results showed that preheat-assisted AFSD repair significantly improved joint bonding and joint strength compared to the control non-preheat substrate ***,increasing rotation speed was also beneficial to improve the metallurgical bonding of the interface and avoid volume *** preheating conditions,the UTS and elongation were positively correlated with rotation *** the process parameters of preheated substrate and tool rotation speed of 1000 r/min,defect-free specimens could be obtained accompanied by tensile fracture occurring in the substrate rather than the repaired *** UTS and elongation reached the maximum values of 164.2MPa and 13.4%,which are equivalent to 99.4%and 140%of the heated substrate,respectively.

关键词： additive friction stir deposition structural repair tool rotation speed Al alloy

Structural macrokinetics of synthesizing ZnFe_2O_4 by mechanical ball milling

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2010年第6期20卷 1131-1135页

作者：赵中伟欧阳全胜王明 School of Metallurgical Science and Engineering Central South University Changsha Engineering and Research institute of Nonferrous metallurgy

Powder mixtures of Fe2O3 and ZnO were milled in a high-energy planetary ball mill to synthesize ZnFe2O4 and X-ray powder diffractometry was used to obtain the relative content of phases,crystallite size and microstrain of both Fe2O3 and ZnFe2O4. The lattice constants of Fe2O3 were obtained by cell refinement *** macrokinetics and the structure evolution of matters were studied and the results show that the dynamics process of mechanochemical synthesis of ZnFe2O4 fits Avrami-Erofe’ev model and is controlled by a nucleation-growth mechanism,and the structural macrokinetics theory in combustion synthesis research area could be used to describe the kinetic process as well.

关键词： mechanochemistry ball milling combustion synthesis structural macrokinetics kinetics model ZnFe2O4

MEASUREMENT　AND　INFLUENCE　FACTOR＇S　ANALYSING　OF　INTERFACIAL　STRENGTH　OF　COMPOSITES

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 1996年第3期6卷 74-78页

作者： Wang Lingsen Liu Ruoyu Zang Jinsen Fan Yi (Research institute of Powder metallurgy, central south University of Technology, Changsha 410083) Research institute of Powder metallurgy Central South University of Technology Changsha 410083 China

ＭＥＡＳＵＲＥＭＥＮＴＡＮＤＩＮＦＬＵＥＮＣＥＦＡＣＴＯＲ＇ＳＡＮＡＬＹＳＩＮＧＯＦＩＮＴＥＲＦＡＣＩＡＬＳＴＲＥＮＧＴＨＯＦＣＯＭＰＯＳＩＴＥＳ￥ＷａｎｇＬｉｎｇｓｅｎ；ＬｉｕＲｕｏｙｕ；ＺａｎｇＪｉｎｓｅｎ；Ｆａ... 详细信息

ＭＥＡＳＵＲＥＭＥＮＴＡＮＤＩＮＦＬＵＥＮＣＥＦＡＣＴＯＲ＇ＳＡＮＡＬＹＳＩＮＧＯＦＩＮＴＥＲＦＡＣＩＡＬＳＴＲＥＮＧＴＨＯＦＣＯＭＰＯＳＩＴＥＳ￥ＷａｎｇＬｉｎｇｓｅｎ；ＬｉｕＲｕｏｙｕ；ＺａｎｇＪｉｎｓｅｎ；ＦａｎＹｉ（ＲｅｓｅａｒｃｈＩｎｓｔｉ...

关键词： composites interfacial strength SiC fiber

Suspension principle of deep-ocean nodule collector

在线全文

学校读者我要写书评

暂无评论

Journal of central south University 2014年第3期21卷 920-925页

作者：郑皓刘少军胡琼 School of Mechanical and Electrical Engineering Central South University State Key Laboratory of Deep Sea Mineral Resources Development and Utilization Technology(Changsha Research institute of mining and metallurgy)

To make sure that the nodule collector can walk on the soft sediments of seafloor effectively, suspension principle of deep-ocean nodule collector is proposed. The supporting and driving mechanisms are separated to avoid collector sinking. The supporting mechanism is a streamlined body with large and smooth supporting area. The grounding pressure is reduced to 0.5- 1 N/cm2 to make sure that the sinkage is limited. The impellers serve as the driving mechanism to supply enough driving power. The position between the supporting mechanism and the driving mechanism can be adjusted according to the operating condition to decrease the walking resistance and to increase driving efficiency. The test results indicate that the collector can walk on the surface of the soft sediments with the limited sinkage. The traction forces were up to 800 kg and the sinkage of the impeller was under the limitation.

关键词： deep-ocean mining suspension principle nodule collector sinking

Prediction of Al(OH)_3 fluidized roasting temperature based on wavelet neural network

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2007年第5期17卷 1052-1056页

作者：李劼刘代飞戴学儒邹忠丁凤其 School of Metallurgical Science and Engineering Central South University Changsha Engineering and Research institute of Nonferrous metallurgy

The recycle fluidization roasting in alumina production was studied and a temperature forecast model was established based on wavelet neural network that had a momentum item and an adjustable learning rate. By analyzing the roasting process, coal gas flux, aluminium hydroxide feeding and oxygen content were ascertained as the main parameters for the forecast model. The order and delay time of each parameter in the model were deduced by F test method. With 400 groups of sample data (sampled with the period of 1.5 min) for its training, a wavelet neural network model was acquired that had a structure of {7 211}, i.e., seven nodes in the input layer, twenty-one nodes in the hidden layer and one node in the output layer. Testing on the prediction accuracy of the model shows that as the absolute error ±5.0 ℃ is adopted, the single-step prediction accuracy can achieve 90% and within 6 steps the multi-step forecast result of model for temperature is receivable.

关键词：子波神经网络氢氧化铝硫化煅烧

Design and implementation of model test installation of heave compensation system of deepsea mining

在线全文

学校读者我要写书评

暂无评论

Journal of central south University 2011年第3期18卷 642-649页

作者：胡琼刘少军郑皓 School of Mechanical and Electrical Engineering Central South University State Key Laboratory of Deep Sea Mineral Resources Development and Utilization Technology Changsha Research Institute of Mining and Metallurgy

In order to validate the simulation model and develop heave compensation control strategy,heave compensation model tests were *** model test installation includes themining ship motion simulator,the heave compensation system,the lifting pipe simulator,the buffer simulator and the water *** tests ofmining ship motion simulator show that it is able to perform under the predetermined attitude path smoothly and can meet the requirements of themining ship *** heave compensation effect is more than 60% under random wave and the goal is set to be 50%.The model test results indicate that this heave compensation system is effective and feasible.

关键词： deepsea mining heave compensation model test installation mining ship motion simulator gimbal