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Mechanisms of phosphate removal from aqueous solution by blast furnace slag and steel furnace slag

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第1期9卷 125-132页

作者： Sheng-gao LU Shi-qiang BAI Hong-dan SHAN College of Environmental and Resource Sciences Zhejiang University Hangzhou 310029 China

We report the adsorption of phosphate and discuss the mechanisms of phosphate removal from aqueous solution by burst furnace slag (BFS) and steel furnace slag (SFS). The results show that the adsorption of phosphate on the slag was rapid and the majority of adsorption was completed in 5~10 min. The adsorption capacity of phosphate by the slag was reduced dramatically by acid treatment. The relative contribution of adsorption to the total removal of phosphate was 26%~28%. Phosphate adsorption on BFS and SFS follows the Freundlich isotherm, with the related constants of k 6.372 and 1/n 1.739 for BFS, and of k 1.705 and 1/n 1.718 for SFS. The pH and Ca2+ concentration were decreased with the addition of phosphate, suggesting the formation of calcium phosphate precipitation. At pH 2.93 and 6.93, phosphate was desorbed by about 36%~43% and 9%~11%, respectively. These results indicate that the P adsorption on the slag is not completely reversible and that the bond between the slag particles and adsorbed phosphate is strong. The x-ray diffraction (xRD) patterns of BFS and SFS before and after phosphate adsorption verify the formation of phosphate salts (CaHPO4·2H2O) after adsorption process. We conclude that the removal of phosphate by BFS and SFS is related to the formation of phosphate calcium precipitation and the adsorption on hydroxylated oxides. The results show that BFS and SFS removed phosphate nearly 100%, indicating they are promising adsorbents for the phosphate removal in wastewater treatment and pollution control.

关键词：废物处理综合利用送风炉炉渣

Research of the terahertz dual-band notch filter based on FSS structures

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Chinese Science Bulletin 2013年第36期58卷 4687-4691页

作者： ZHANG JinLing ZHANG Yu gao Ke ZHAO GuoZhong School of Electronic Engineering Beijing University of Posts and Telecommunications School of Physics Capital Normal University

In this paper,a dual-band notch filter for two-layer frequency selective surface(FSS)at terahertz(THz)frequency with high filtering performance has been realized on high-resistivity silicon *** periodic metallic resonators patterned on the silicon wafer,the designed filter can provide two tunable resonant frequencies for terahertz *** transmission response was improved by introducing an extra surrounding pattern around the T-shaped structure,and the location of transmission drop was tuned independently with geometric *** by finite-integral time-domain method,the filter is designed to operate between 0.2 and 0.6 THz with dual-band band-stop performance,a salient feature of this design is making the low sensitivity of its frequency response to the incident angles,which allows to place the filter close to the radiation source with spherical wave *** proposed structures were fabricated using photolithography and tested by THz time-domain spectroscopy *** results show that the transmission response has more than 12 and 32 dB rejections near 285 and 460 GHz respectively,which is in good agreement with the simulation result.

关键词：陷波滤波器太赫兹波 T形结构双频段 FSS 太赫兹时域光谱频率选择表面谐振频率

Mechanism of protective film formation during CO_2 corrosion of x65 pipeline steel

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Journal of University of Science and Technology Beijing 2008年第6期15卷 702-706页

作者： Tong Li Yonggjin Yang Kewei gao Minxu Lu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Corrosion and Protection Center University of Science and Technology Beijing Beijing 100083 China

Electrochemical techniques, x-ray diffraction （xRD）, and scanning electron microscopy （SEM） were applied to study the corrosion behaviors of x65 steel in static solution with carbon dioxide （CO2） at 65℃. The results show that iron carbonate （FeCO3） deposits on the steel surface as a corrosion product scale. This iron carbonate scale acts as a barrier to CO2 corrosion, and can reduce the general corrosion rate. The protection ability of the scale is closely related to the scale morphological characteristics.

关键词： pipeline steel carbon dioxide corrosion product scale protective film iron carbonate

PREPARATION OF NANOSIZED SILICON NITRIDE POWDERS BY AMMONO SOL-GEL PROCESSING

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中国有色金属学会会刊：英文版 1997年第3期7卷 22-25页

作者： gao, Jiming xiao, Hanning Zhang, Li Du, Haiqing Hunan Univ Changsha China

ＰＲＥＰＡＲＡＴＩＯＮＯＦＮＡＮＯＳＩＺＥＤＳＩＬＩＣＯＮＮＩＴＲＩＤＥＰＯＷＤＥＲＳＢＹＡＭＭＯＮＯＳＯＬＧＥＬＰＲＯＣＥＳＳＩＮＧ①ＧａｏＪｉｍｉｎｇ，ＸｉａｏＨａｎｎｉｎｇ，ＺｈａｎｇＬｉ，ＤｕＨａｉｑｉｎｇ... 详细信息

ＰＲＥＰＡＲＡＴＩＯＮＯＦＮＡＮＯＳＩＺＥＤＳＩＬＩＣＯＮＮＩＴＲＩＤＥＰＯＷＤＥＲＳＢＹＡＭＭＯＮＯＳＯＬＧＥＬＰＲＯＣＥＳＳＩＮＧ①ＧａｏＪｉｍｉｎｇ，ＸｉａｏＨａｎｎｉｎｇ，ＺｈａｎｇＬｉ，ＤｕＨａｉｑｉｎｇＣｈｅｍｉｓｔｒｙａｎｄＣｈｅｍｉ...

关键词： silicon nitride nanosized powder ammonolysis sol gel

Regulatory perspectives of combination products

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Bioactive Materials 2022年第4期7卷 492-503页

作者： Jiaxin Tian xu Song Yongqing Wang Maobo Cheng Shuang Lu Wei xu Guobiao gao Lei Sun Zhonglan Tang Minghui Wang xingdong Zhang Center for Medical Device Evaluation National Medical Products AdministrationBeijingChina NMPA Key Laboratory for Quality Research and Control of Tissue Regenerative Biomaterial&Institute of Regulatory Science for Medical Devices&NMPA Research Base of Regulatory Science for Medical Devices Sichuan UniversityChengduChina National Engineering Research Center for Biomaterials&College of Biomedical Engineering Sichuan UniversityChengduChina Center for Drug Evaluation National Medical Products AdministrationBeijingChina

Combination products with a wide range of clinical applications represent a unique class of medical products that are composed of more than a singular medical device or drug/biological *** product research and development,clinical translation as well as regulatory evaluation of combination products are complex and *** review firstly introduced the origin,definition and designation of combination *** areas of systematic regulatory review on the safety and efficacy of device-led/supervised combination products were then *** and clinical evaluation of combination products was ***,the research prospect of regulatory science for combination products was *** tools of computational modeling and simulation,novel technologies such as artificial intelligence,needs of developing new standards,evidence-based research methods,new approaches including the designation of innovative or breakthrough medical products have been developed and could be used to assess the safety,efficacy,quality and performance of combination *** together,the fast development of combination products with great potentials in healthcare provides new opportunities for the advancement of regulatory review as well as regulatory science.

关键词： Combination products Definition Designation Safety and efficacy Regulatory science

Antibacterial Activity and Mechanism of ZnO/Cu^(2+)-Chitosan/Montmorillonite

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Journal of Wuhan University of Technology(Materials Science) 2021年第4期36卷 510-516页

作者：麻晓霞 gao Lingjuan 马玉龙 ZHANG xiaoguang State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia UniversityTinchuart 750021China

A new composite antibacterial material ZnO/Cu^(2+)-Chitosan/Montmorillonite (ZCCM) was prepared with montmorillonite as carrier,Zn(Ac)_(2)·2H_(2)O,Cu(NO_(3))_(2)·3H_(2)O and chitosan as raw *** was characterized by x-ray diffraction,nitrogen physical adsorption,scanning electron microscopy and energy dispersion *** antibacterial activity of ZCCM against Escherichia coli,Salmonella typhimurium,and Staphylococcus aureus was evaluated by minimal inhibitory concentration,minimum bactericidal concentration and the influence of growth *** displays excellent antibacterial activity which is higher than ZnO-Montmorillonite,Cu^(2+)-Montmorillonite and ZnO/Cu^(2+)-*** addition,the antibacterial mechanism of ZCCM was investigated by analyzing bacterial morphology,integrity of cell membrane,lipid peroxidation and the effect of histidine on antibacterial activity of *** is found that cell morphologies of bacteria are damaged and bacterial cells are *** the increase of cell membrane permeability,the intracellular dissolved matters leak ***’s more,the reactive oxygen species are generated and biomacromolecules are oxidized.

关键词： montmorillonite chitosan ZnO Cu^(2+) antibacterial mechanism

Research on cigarette during smoking based on reverse engineering and numerical simulation

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2359-2375页

作者： Darong Tang JunzhangWu Jinsong Zeng Wenhua gao Liang Du State Key Laboratory of Pulp and Paper Engineering Plant Micro/Nano Fiber Research CenterSouth China University of TechnologyGuangzhou 510640China China Tobacco Guangdong Industrial Co.Ltd. Guangzhou 510385China

The three-dimensional(3 D)model of cigarette was accurately constructed through reverse engineering as the research object of numerical *** combustion process of cigarette was studied with computational fluid dynamics(CFD).Standard Laminar models with species transport approach were applied,and numerical simulation of the cigarette was analyzed with semi-implicit method for pressure–velocity *** results showed that the model could predict velocity of cigarette smoke,the distributions of temperature and pressure at different *** order to verify the correctness of model,it was found that the relationship between the velocity of smoke and pressure according to Darcy’s law on z position(x=4 mm,y=0,0 mm≤z≤50.61 mm).

关键词： Cigarette Reverse engineering Computational fluid dynamics

Semisolid A356 alloy feedstock poured through a serpentine channel

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International Journal of Minerals,Metallurgy and Materials 2009年第5期16卷 603-607页

作者： xiao-rong Yang Wei-min Mao Chong gao School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China School of Materials Science and Engineering Taiyuan University of Science and Technology Taiyuan 030024 China

Fine spheroidal and equiaxed nondendritic microstructures required for semisolid casting can be formed through a serpentine pouting channel. Effects of the pouring temperature and the vertical section length of the serpentine pouring channel were studied. The results indicate that both favorable semisolid microstructures of A356 aluminum alloy can be generated by a serpentine pouring channel, and the solid shell inside the channel can be avoided when the pouting temperature is in the range from 660 to 680℃. It is also shown that the vertical section length of the serpentine pouting channel has a significant influence on the microstructure of the feedstock, namely both the microstructure of the feedstock and the microstructure uniformity in the radial direction get worse when the vertical section length is shortened; moreover, the pouring temperature for obtaining the feedstock with suitable microstructure decreases. The relevant mechanisms were discussed.

关键词： semisolid microstructure serpentine channel primary α-A1

Development of a linear compressor for two-stage pulse tube cryocoolers

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第11期10卷 1595-1600页

作者： Peng-da YAN Wei-li gao Guo-bang CHEN Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

A valveless linear compressor was built up to drive a self-made two-stage pulse tube cryocooler. With a designed maximum swept volume of 60 cm3, the compressor can provide the cryocooler with a pressure volume (PV) power of 400 W. Preliminary measurements of the compressor indicated that both an efficiency of 35%～55% and a pressure ratio of 1.3～1.4 could be obtained. The two-stage pulse tube cryocooler driven by this compressor achieved the lowest temperature of 14.2 K.

关键词：线性压缩机脉管制冷机开发最低温度两阶段压力比无阀