摘要：
The adsorption of chromium (VI) ions from aqueous solution by ethylenediamine-modified cross-linked magnetic chitosan resin (EMCMCR) was studied in a batch adsorption system. Chromium (VI) removal is pH dependent and the optimum adsorption was observed at pH 2.0. The adsorption rate was extremely fast and the equilibrium was established within 6-10 min. The adsorption data could be well interpreted by the Langmuir and Temkin model. The maximum adsorption capacities obtained from the Langmuir model are 51.813 mg g(-1), 48.780 mg g(-1) and 45.872 mg g(-1) at 293, 303 and 313 K, respectively. The adsorption process could be described by pseudo-second-order kinetic model. The intraparticle diffusion study revealed that film diffusion might be involved in the present case. Thermodynamic parameters revealed the feasibility, spontaneity and exothermic nature of adsorption. The sorbents were successfully regenerated using 0.1 N NaOH solutions. (C) 2010 Elsevier B.V. All rights reserved.
期刊：
Journal of Environmental Radioactivity,2010年101(6):504-508 ISSN：0265-931X
通讯作者：
Wang, Jing-song
作者机构：
[Wang, Jing-song; Bao, Zheng-lei; Xie, Shui-bo; Hu, Xin-jiang] Univ S China, Sch Urban Construct, Hengyang 421001, Hunan, Peoples R China.;[Wang, Jing-song; Xie, Shui-bo] Univ S China, Hunan Key Lab Pollut Control & Resource Reuse, Henyang 421001, Hunan, Peoples R China.;[Liu, Yun-guo; Hu, Xin-jiang] Hunan Univ, Coll Environm Sci & Engn, Changsha 410082, Hunan, Peoples R China.;[Wang, Jing-song] Univ S China, Sch Urban Construct, 28 W Changsheng Rd, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Wang, Jing-song] Univ S China, Sch Urban Construct, 28 W Changsheng Rd, Hengyang 421001, Hunan, Peoples R China.
会议名称：
9th International Conference on Biogeochemistry of Trace Elements
会议时间：
JUL, 2007
会议地点：
Beijing, PEOPLES R CHINA
会议主办单位：
[Wang, Jing-song;Hu, Xin-jiang;Xie, Shui-bo;Bao, Zheng-lei] Univ S China, Sch Urban Construct, Hengyang 421001, Hunan, Peoples R China.^[Wang, Jing-song;Xie, Shui-bo] Univ S China, Hunan Key Lab Pollut Control & Resource Reuse, Henyang 421001, Hunan, Peoples R China.^[Hu, Xin-jiang;Liu, Yun-guo] Hunan Univ, Coll Environm Sci & Engn, Changsha 410082, Hunan, Peoples R China.
关键词：
Immobilized beads;Aspergillus fumigatus;Biosorption;Uranium (VI);Pseudo-second order
摘要：
Biosorption of uranium (VI) ions by immobilized Aspergillus fumigatus beads was investigated in a batch system. The influences of solution pH, biosorbent dose, U (VI) concentration, and contact time on U (VI) biosorption were studied. The results indicated that the adsorption capacity was strongly affected by the solution pH, the biosorbent dose and initial U (VI) concentration. Optimum biosorption was observed at pH 5.0, biosrobent dose (w/v) 2.5%, initial U (VI) concentration 60 mg L(-1). Biosorption equilibrium was established in 120 min. The adsorption process conformed to the Freunlich and Temkin isothermal adsorption models. The dynamic adsorption model conformed to pseudo-second order model. (C) 2010 Elsevier Ltd. All rights reserved.
摘要：
Air-stable hypervalent organobismuth(III) tetrafluoroborate (C6H11N(CH2C6H4)2BiBF4) was synthesized and characterized by spectroscopic and X-ray crystallographic techniques. The compound shows good catalytic efficiency in the allylation reaction of different aldehydes with tetraallyltin in a medium of aqueous methanol, giving the corresponding homoallylic alcohols in excellent chemoselectivity and yields.
摘要：
An air-stable hypervalent organobismuth (III) perfluorooctanesulfonate was synthesized and characterized by spectroscopic and X-ray crystallographic techniques, and found to exhibit high catalytic efficiency towards one-pot Mannich-type reaction of ketones with aromatic aldehydes and aromatic amines in water. This catalyst also shows good recyclability and reusability. This catalytic system would provide a simple, efficient and 'green' avenue towards the synthesis of beta-amino ketones. (C) 2009 Published by Elsevier B.V.
摘要：
The healthy development of the city has received widespread attention in the world, and urban resilience is an important issue in the study of urban development. In order to better provide a useful reference for urban resilience and urban health development, this paper takes 56 cities in China as the research object, and selects 29 indicators from urban infrastructure, economy, ecology and society. The combination weight method, exploratory spatial data analysis (ESDA) and spatial measurement model are used to explore the spatial distribution of urban resilience and its influencing factors. From 2006 to 2017, the urban resilience of prefecture-level cities in the four provinces showed a wave-like rise. During the study period, the urban resilience values, measured as Moran's Is, were greater than 0.3300, showing a significantly positive correlation in regard to their spatial distribution. Regarding the local spatial correlation, the urban resilience of the study area had spatial agglomeration characteristics within the province, with a significant distribution of "cold hot spots" in the spatial distribution. From the perspective of the factors that affected urban resilience, the proportion of the actual use of foreign capital in GDP and carbon emissions per 10,000 CNY of GDP had a negative impact and GDP per square kilometer, the proportion of urban pension insurance coverage, the proportion of the population with higher education, and expenditure to maintain and build cities had a positive impact. The development strategy of urban resilience must be combined with the actual situation of the region, and the rational resilience performance evaluation system and the top-level design of urban resilience improvement should be formulated to comprehensively improve urban resilience.
期刊：
Current Microbiology,2009年59(2):107-112 ISSN：0343-8651
通讯作者：
Shi, Shunyu
作者机构：
[Shi, Shunyu] Chinese Acad Sci, S China Sea Inst Oceanol, Key Lab Trop Marine Environm Dynam, Guangzhou, Guangdong, Peoples R China.;[Tang, Dongshan] Univ S China, Sch Urban Construct, Hengyang, Hunan, Peoples R China.;[Liu, Yongding] Chinese Acad Sci, Inst Hydrobiol, State Key Lab Freshwater Ecol & Biotechnol, Guangzhou, Guangdong, Peoples R China.
通讯机构：
[Shi, Shunyu] Chinese Acad Sci, S China Sea Inst Oceanol, Key Lab Trop Marine Environm Dynam, Guangzhou, Guangdong, Peoples R China.
关键词：
Reactive Oxygen Species Production;Cyanobacterial Cell;Paralytic Shellfish Poisoning;Algicidal Activity;Reactive Oxygen Species Content
摘要：
Evident effect of an algicidal bacterium Pseudomonas mendocina on the growth and antioxidant system of Aphanizomenon flos-aquae was detected in this experiment. Seven parameters including the chlorophyll a contents, Fv/Fm values, reactive oxygen species (ROS), malonaldehyde (MDA), catalase (CAT), peroxide dismutase (POD), and superoxide dismutase (SOD) were tested in the cyanobacterium A. flos-aquae cells after inoculation with the algicidal bacterium Pseudomonas mendocina DC10. It was shown from the experiment that the growth of the treated cyanobacterium A. flos-aquae was significantly restrained, which was expressed as great reductions in the chlorophyll a contents and Fv/Fm values. At the same time, the treated cyanobacterial cells exhibited an obvious increase in the production of ROS and MDA compared with the control. CAT and POD activities in the treated group kept at high level, however, they both reduced significantly on day 6. SOD activities in the treated A. flos-aquae showed obvious declines after inoculation, and great augmentations on day 3 and 4, thereafter, they kept in a declining tendency. The results showed the oxidative stresses induced by the bacterium could be a killing agent of the cyanobacterium A. flos-aquae cells.
摘要：
In order to investigate the mechanism of extracellular polymeric substances (EPS) influencing sludge characteristics, variations of extractable EPS from municipal sewage sludge by acid/alkaline pretreatment and gamma-ray irradiation were studied. The changes in constituents of EPS were analyzed by UV-vis spectra and SEM images. The effects of alkaline pretreatment and gamma-ray irradiation on the functional groups in EPS were investigated by Fourier transform infrared (FTIR) spectrometer. Results showed that the extractable EPS increased clearly with increasing irradiation dose from 0 to 15 kGy. UV-vis spectra indicated that a new absorption band from 240 nm to 300 nm existed in all irradiated samples, apart from acid condition. The results of FTIR spectroscopic analysis indicated that, irradiation influenced major functional groups in EPS, such as protein and polysaccharide, and these effects were clearer under alkaline condition. SEM images provided that after alkaline hydrolysis, gamma-ray irradiation was more effective in resulting in the sludge flocs and cells broken, compared with acid pretreatment (pH 2.50). (c) 2013 Published by Elsevier Ltd.
作者机构：
[Xie, Dong; Wang, Yun; Mo, Shunquan; Liao, Maili] Univ South China, Sch Urban Construct, Hengyang 421001, Peoples R China.;[Xie, Dong; Wang, Hanqing] Cent S Univ, Sch Energy Sci & Engn, Changsha 410083, Hunan, Peoples R China.;[Wang, Hanqing] Hunan Univ Commerce, Changsha 410205, Hunan, Peoples R China.
通讯机构：
[Xie, Dong] Univ South China, Sch Urban Construct, Hengyang 421001, Peoples R China.
关键词：
Capillary ceiling radiant cooling panel;Distribution of temperature non-uniformity;Cooling capacity;CFD;Numerical analysis
摘要：
Capillary ceiling radiant cooling panel is a high temperature cooling system, which could pose low energy consumption to meet thermal comfort requirements. A computational fluid dynamics (CFD) simulation study on heat transfer of chilled water flow in the capillary of ceiling radiant cooling panel was performed to attain surface temperature distributions and cooling capacities. Six influencing factors included chilled water inlet parameters, conditions of gypsum plaster and capillary mats structural parameters were considered to obtain the complicated relationships between capillary radiant panel conditions and heat transfer performance. The index of temperature non-uniformity coefficient was proposed to evaluate temperature profiles of ceiling panel surface. The results of the simulation were compared with the values depicted in ASHRAE Handbook and good agreement had been achieved. The average difference between simulation results and the values reported by ASHRAE handbook was within the region of 15%. The research results showed that temperature non-uniformity coefficient was negatively correlated with temperature of chilled inlet water (linear correlation), water velocity (correlation coefficient R = -0.85), and pipe diameter (correlation coefficient R = -0.93), but positively and linearly correlated with tube spacing. Cooling capacity was found to have negative linear correlation with temperature of chilled inlet water, covering thickness and tube spacing. (C) 2015 Elsevier Ltd. All rights reserved.
摘要：
Fe(II)-Al(III) layered double hydroxides (Fe-Al LDHs) were prepared by the sono-assisted precipitation method and used for the removal of uranium (VI) from aqueous solutions. The application of ultrasound in the Fe-Al LDHs preparation promoted the formation of the hydrotalcite-like phase and improved the adsorption capacity of U(VI). Batch experiments were carried out to investigate the influence of solid-to-solution ratio, initial U(VI) concentration, initial pH, contact time and temperature on the U(VI) removal process. The experimental results indicated that the removal process of U(VI) could be well described by the pseudo-second-order kinetic model. The equilibrium isotherm for U(VI) removal was fitted by the Langmuir model and the maximum adsorption capacity of Fe-Al LDHs was 113.64 mg/g at a temperature of 308 K. The thermodynamic parameters implied that the removal of U(VI) was essentially an endothermic process. The FT-IR, EDX and XPS results suggested that the removal mechanism involves combined adsorption-reduction processes. When the U(VI) ions absorbed onto the Fe-Al LDHs through physical adsorption, the Fe(II) in the structure of Fe-Al LDHs reduces U(VI) to U(IV) while Fe(II) was oxidized to Fe(III). (C) 2017 Elsevier B.V. All rights reserved.
摘要：
This study investigates the impact behavior of concrete beams using drop-weight facility. Different tups were used and varying drop weights and heights were applied. This study measures impact loads, mid-span accelerations, and strains at the top and bottom edges of the beam. To distinguish the inertial and bending components of impact forces, inertial force is formulated based on elastic beam theory. When the strain rate ranges between 0.1 s(-1) and 4 s(-1), rate effect is significant given corresponding dynamic increase factors ranging from 1.6 to 3.4. Finally, the equilibrium of momentum-impulse and energy conversion are examined. (C) 2014 Elsevier Ltd. All rights reserved.
摘要：
Taking the heterogeneity character of concrete into account, this paper presents an equivalent probabilistic model for failure study of concrete in which the heterogeneity of concrete is considered by assuming that the material properties conform to the Weibull distribution law and by using mesoscale mesh of finite elements. The study is divided into three parts. In the first part, a spatial correlation length factor is developed into the Weibull distribution formula so that the spatial correlation of local continuity of material properties can be considered. The second part presents a series of numerical analyses for investigating the size effect of self-compacting concrete (SCC) based on the equivalent probabilistic model, and a comparison is made between the simulation results and compression test measurements for illustrating the size effect on uniaxial compression strength and failure pattern of the SCC concerned. It is shown that the numerical model can provide reasonable predictions in the analysis of the size effect of SCC. In the final part, as an engineering application of the presented model, the damage and fracture behavior of the Koyna gravity dam during the 1967 earthquake are analyzed. Influences of concrete parameters on the crack pattern and failure modes of the dam prototype during the event are discussed. DOI: 10.1061/(ASCE)MT.1943-5533.0000179. (C) 2011 American Society of Civil Engineers.
摘要：
This paper is concerned with the generalized Hamy symmetric function Sigma(n)(x, r; f) = Sigma(1 <= i1<i2<...<ir <= n) f(Pi(r)(j=1) x(ij)(1/r)), where f is a positive function defined in a subinterval of (0, +infinity). Some properties, including Schur-convexity, geometric Schur-convexity and harmonic Schur-convexity are investigated. As applications, several inequalities are obtained, some of which extend the known ones. (C) 2010 Elsevier Inc. All rights reserved.
