资源类型

期刊论文 47

年份

2023 7

2022 7

2021 2

2020 2

2019 5

2018 4

2017 3

2016 3

2015 2

2013 3

2012 1

2011 1

2009 2

2007 2

2001 1

展开 ︾

关键词

7815 1

CMAQ模型 1

PM2.5 1

T试剂 1

严重急性呼吸综合征冠状病毒2 1

中国 1

大气年龄 1

微污染物 1

控制措施 1

新型冠状病毒肺炎 1

方舱医院 1

气溶胶 1

硫酸根离子 1

硫酸镍;红土镍矿湿法冶炼;动力电池;回收利用 1

萃取 1

链式反应 1

1

顺序电化学体系 1

高级氧化 1

展开 ︾

检索范围:

排序: 展示方式:

Improving simulations of sulfate aerosols during winter haze over Northern China: the impacts of heterogeneous

Meng Gao,Gregory R. Carmichael,Yuesi Wang,Dongsheng Ji,Zirui Liu,Zifa Wang

《环境科学与工程前沿(英文)》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0878-2

摘要: Incorporating the missing heterogeneous oxidation of S(IV) by NO into the WRF-Chem model. Sulfate production is not sensitive to increase in SO emission. The newly added reaction reproduces sulfate concentrations well during winter haze. We implemented the online coupled WRF-Chem model to reproduce the 2013 January haze event in North China, and evaluated simulated meteorological and chemical fields using multiple observations. The comparisons suggest that temperature and relative humidity (RH) were simulated well (mean biases are -0.2K and 2.7%, respectively), but wind speeds were overestimated (mean bias is 0.5 m?s ). At the Beijing station, sulfur dioxide (SO ) concentrations were overpredicted and sulfate concentrations were largely underpredicted, which may result from uncertainties in SO emissions and missing heterogeneous oxidation in current model. We conducted three parallel experiments to examine the impacts of doubling SO emissions and incorporating heterogeneous oxidation of dissolved SO by nitrogen dioxide (NO ) on sulfate formation during winter haze. The results suggest that doubling SO emissions do not significantly affect sulfate concentrations, but adding heterogeneous oxidation of dissolved SO by NO substantially improve simulations of sulfate and other inorganic aerosols. Although the enhanced SO to sulfate conversion in the HetS (heterogeneous oxidation by NO ) case reduces SO concentrations, it is still largely overestimated by the model, indicating the overestimations of SO concentrations in the North China Plain (NCP) are mostly due to errors in SO emission inventory.

关键词: Sulfate aerosols     Winter haze     WRF-Chem     Northern China    

Effects of two transition metal sulfate salts on secondary organic aerosol formation in toluene/NO

Biwu CHU, Jiming HAO, Junhua LI, Hideto TAKEKAWA, Kun WANG, Jingkun JIANG

《环境科学与工程前沿(英文)》 2013年 第7卷 第1期   页码 1-9 doi: 10.1007/s11783-012-0476-x

摘要: Aerosol phase reactions play a very important role on secondary organic aerosol (SOA) formation, and metal-containing aerosols are important components in the atmosphere. In this study, we tested the effects of two transition metal sulfate salts, manganese sulfate (MnSO ) and zinc sulfate (ZnSO ), on the photochemical reactions of a toluene/NO photooxidation system in a 2 m smog chamber. By comparing photochemical reaction products of experiments with and without transition metal sulfate seed aerosols, we evaluated the effects of transition metal sulfate seed aerosols on toluene consumption, NO conversion and the formation of ozone and SOA. MnSO and ZnSO seed aerosols were found to have similar effects on photochemical reactions, both enhance the SOA production, while showing negligible effects on the gas phase compounds. These observations are consistent when varying metal sulfate aerosol concentrations. This is attributed to the catalytic effects of MnSO and ZnSO seed aerosols which may enhance the formation of condensable semivolatile compounds. Their subsequent partitioning into the aerosol phase leads to the observed SOA formation enhancement.

关键词: manganese sulfate     zinc sulfate     seed aerosols     toluene photooxidation     secondary organic aerosol    

Effects of natural zeolite and sulfate ions on the mechanical properties and microstructure of plastic

《结构与土木工程前沿(英文)》 2022年 第16卷 第1期   页码 86-98 doi: 10.1007/s11709-021-0793-x

摘要: One of the strategic materials used in earth-fill embankment dams and in modifying and preventing groundwater flow is plastic concrete (PlC). PlC is comprised of aggregates, water, cement, and bentonite. Natural zeolite (NZ) is a relatively abundant mineral resource and in this research, the microstructure, unconfined strength, triaxial behavior, and permeability of PlC made with 0%, 10%, 15%, 20%, and 25% replacement of cement by NZ were studied. Specimens of PIC-NZ were subjected to confined conditions and three different confining pressures of 200, 350, and 500 kPa were used to investigate their mechanical behavior and permeability. To study the effect of sulfate ions on the properties of PlC-NZ specimens, the specimens were cured in one of two different environments: normal condition and in the presence of sulfate ions. Results showed that increasing the zeolite content decreases the unconfined strength, elastic modulus, and peak strength of PlC-NZ specimens at the early ages of curing. However, at the later ages, increasing the zeolite content increases unconfined strength as well as the peak strength and elastic modulus. Specimens cured in the presence of sulfate ions indicated lower permeability, higher unconfined strength, elastic modulus, and peak strength due to having lower porosity.

关键词: plastic concrete     sulfate resistance     natural zeolite     triaxial compression test     SEM     permeability    

A time−space porosity computational model for concrete under sulfate attack

《结构与土木工程前沿(英文)》 doi: 10.1007/s11709-023-0985-7

摘要: The deterioration of the microscopic pore structure of concrete under external sulfate attack (ESA) is a primary cause of degradation. Nevertheless, little effort has been invested in exploring the temporal and spatial development of the porosity of concrete under ESA. This study proposes a mechanical–chemical model to simulate the spatiotemporal distribution of the porosity. A relationship between the corrosion damage and amount of ettringite is proposed based on the theory of volume expansion. In addition, the expansion strain at the macro-scale is obtained using a stress analysis model of composite concentric sphere elements and the micromechanical mean-field approach. Finally, considering the influence of corrosion damage and cement hydration on the diffusion of sulfate ions, the expansion deformation and porosity space−time distribution are obtained using the finite difference method. The results demonstrate that the expansion strains calculated using the suggested model agree well with previously reported experimental results. Moreover, the tricalcium aluminate concentration, initial elastic modulus of cement paste, corrosion damage, and continuous hydration of cement significantly affect concrete under ESA. The proposed model can forecast and assess the porosity of concrete covers and provide a credible approach for determining the residual life of concrete structures under ESA.

关键词: expansion deformation     porosity     internal expansion stress     external sulfate attack     mechanical–chemical coupling model    

Biological conversion pathways of sulfate reduction ammonium oxidation in anammox consortia

Zhen Bi, Deqing Wanyan, Xiang Li, Yong Huang

《环境科学与工程前沿(英文)》 2020年 第14卷 第3期 doi: 10.1007/s11783-019-1217-1

摘要: The SRAO phenomena tended to occur only under certain conditions. High amount of biomass and non-anaerobic condition is requirement for SRAO. Anammox bacteria cannot oxidize ammonium with sulfate as electron acceptor. AOB and AnAOB are mainly responsible for ammonium conversion. Heterotrophic sulfate reduction mainly contributed to sulfate conversion. For over two decades, sulfate reduction with ammonium oxidation (SRAO) had been reported from laboratory experiments. SRAO was considered an autotrophic process mediated by anammox bacteria, in which ammonium as electron donor was oxidized by the electron acceptor sulfate. This process had been attributed to observed transformations of nitrogenous and sulfurous compounds in natural environments. Results obtained differed largely for the conversion mole ratios (ammonium/sulfate), and even the intermediate and final products of sulfate reduction. Thus, the hypothesis of biological conversion pathways of ammonium and sulfate in anammox consortia is implausible. In this study, continuous reactor experiments (with working volume of 3.8L) and batch tests were conducted under normal anaerobic (0.2≤DO<0.5 mg/L) / strict anaerobic (DO<0.2 mg/L) conditions with different biomass proportions to verify the SRAO phenomena and identify possible pathways behind substrate conversion. Key findings were that SRAO occurred only in cases of high amounts of inoculant biomass under normal anaerobic condition, while absent under strict anaerobic conditions for same anammox consortia. Mass balance and stoichiometry were checked based on experimental results and the thermodynamics proposed by previous studies were critically discussed. Thus anammox bacteria do not possess the ability to oxidize ammonium with sulfate as electron acceptor and the assumed SRAO could, in fact, be a combination of aerobic ammonium oxidation, anammox and heterotrophic sulfate reduction processes.

关键词: Anammox bacteria     Autotrophic     Biological conversion     Sulfate reducing ammonium oxidation (SRAO)    

Removal of virus aerosols by the combination of filtration and UV-C irradiation

《环境科学与工程前沿(英文)》 2023年 第17卷 第3期 doi: 10.1007/s11783-023-1627-y

摘要:

● The removal of virus aerosols by filtration and UV-C irradiation was proposed.

关键词: Filtration system     UV-C irradiation     Virus aerosol     Public health     COVID-19    

Single particle analysis of ambient aerosols in Shanghai during the World Exposition, 2010: two case

Shikang TAO, Xinning WANG, Hong CHEN, Xin YANG, Mei LI, Lei LI, Zhen ZHOU

《环境科学与工程前沿(英文)》 2011年 第5卷 第3期   页码 391-401 doi: 10.1007/s11783-011-0355-x

摘要: A TSI Model 3800 aerosol time-of-flight mass spectrometer (ATOFMS) was deployed for single-particle analysis in Shanghai during the World Exposition (EXPO), 2010. Measurements on two extreme cases: polluted day (1st May) and clean day (25th September) were compared to show how meteorological conditions affected the concentration and composition of ambient aerosols. Mass spectra of 90496 and 50407 particles were analyzed respectively during the two sampling periods. The ART-2a neural network algorithm was applied to sort the collected particles. Seven major classes of particles were obtained: dust, sea salt, industrial, biomass burning, organic carbon (OC), elementary carbon (EC), and NH -rich particles. Number concentration of ambient aerosols showed a strong anti-correlation with the boundary layer height variation. The external mixing states of aerosols were quite different during two sampling periods because of different air parcel trajectories. Number fraction of biomass burning particles (43.3%) during polluted episode was much higher than that (21.6%) of clean time. Air parcels from the East China Sea on clean day diluted local pollutant concentration and increased the portion of sea salt particle dramatically (13.3%). The large contribution of biomass burning particles in both cases might be an indication of a constant regional background of biomass burning emission. Mass spectrum analysis showed that chemical compositions and internal mixing states of almost all the particle types were more complicate during polluted episode compared with those observed in clean time. Strong nitrate signals in the mass spectra suggested that most of the particles collected on polluted day had gone through some aging processes before reaching the sampling site.

关键词: ambient aerosol     aerosol time-of-flight mass spectrometer     Shanghai     world exposition    

The solubility of cefquinome sulfate in pure and mixed solvents

Rongbao Qi,Jingkang Wang,Junxiao Ye,Hongxun Hao,Ying Bao

《化学科学与工程前沿(英文)》 2016年 第10卷 第2期   页码 245-254 doi: 10.1007/s11705-016-1569-z

摘要: Solid-liquid equilibrium data of cefquinome sulfate is important to develop industrial crystallization processes for cefquinome sulfate. The solubilities of cefquinome sulfate in five pure solvents (methanol, ethanol, ethylene glycol, acetic acid and water) from 277.15 to 305.15 K and in a binary acetone-water solvent from 278.15 to 293.15 K were measured at atmospheric pressure. The pure-solvent solubility data was correlated to the modified Apelblat and Van’t Hoff equations whereas the mixed-solvent system data was correlated to the modified Apelblat, Van’t Hoff, CNIBS/R-K and Jouyban-Acree models. It was found that the solubilities of cefquinome sulfate in all tested solvents decreased with the increasing of temperature. In addition, the thermodynamic properties of the dissolution processes, including standard Gibbs free energy, enthalpy and entropy changes, were calculated using the Van’t Hoff equation. It was found that the dissolution of cefquinome sulfate is exothermic.

关键词: cefquinome sulfate     solubility     thermodynamic properties    

Effects of metal ions on the morphology of calcium sulfate hemihydrate whiskers by hydrothermal method

Tianjie Liu, Hao Fan, Yanxia Xu, Xingfu Song, Jianguo Yu

《化学科学与工程前沿(英文)》 2017年 第11卷 第4期   页码 545-553 doi: 10.1007/s11705-017-1665-8

摘要: The effects of Na , Mg , Al and Fe ion concentrations on the crystal morphology of calcium sulfate hemihydrate whiskers formed via a hydrothermal method have been studied. In the presence of Al concentrations higher than 1×10 mol/L the whiskers were significantly shorter and thicker and the presence of Mg and Fe resulted in shorter whiskers. The presence of Na did not affect the morphology of the whiskers. Through elemental analysis, it was determined that Mg and Al were selectively adsorbed on the surfaces of the crystals, whereas Fe underwent a hydrolysis reaction to form a brown precipitate which decreased the ion concentration in the solution. These results indicate that in raw materials used for the industrial preparation of calcium sulfate whiskers, Al and Fe should be removed and the Mg concentration should be less than 8 × 10 mol/L in order to obtain pure whiskers with high aspect ratios.

关键词: metal ions     morphology     calcium sulfate hemihydrate whiskers     hydrothermal method     selective adsorption    

PICRUSt2 functionally predicts organic compounds degradation and sulfate reduction pathways in an acidogenic

《环境科学与工程前沿(英文)》 doi: 10.1007/s11783-021-1481-8

摘要:

For comprehensive insights into the influences of sulfate on performance, microbial community and metabolic pathways in the acidification phase of a two-phase anaerobic system, a laboratory-scale acidogenic bioreactor was continuously operated to treat wastewater with elevated sulfate concentrations from 2000 to 14000 mg/L.

关键词: Acidogenic phase reactor     High-sulfate wastewater     Sulfate reduction     Acidogenic fermentation     PICRUSt2    

Thermal decomposition mechanism of ammonium sulfate catalyzed by ferric oxide

Xingfu SONG, Jingcai ZHAO, Yunzhao LI, Ze SUN, Jianguo YU

《化学科学与工程前沿(英文)》 2013年 第7卷 第2期   页码 210-217 doi: 10.1007/s11705-013-1320-y

摘要: The decomposition mechanism of ammonium sulfate catalyzed by ferric oxide was investigated in this paper. The decomposition kinetics parameters were determined via a global optimization of the Kissinger iterative method using the non-isothermal thermogravimetric analysis data. The products and intermediates were synchronously characterized by X-ray diffraction and mass spectrometry. The obtained results indicate that the decomposition process of ammonium sulfate catalyzed by ferric oxide can be divided into four stages of which the activation energies are 123.64, 126.58, 178.77 and 216.99 kJ·mol respectively. The decomposition mechanisms at the first and the fourth stage both belong to Mample power theorem, the second stage belongs to Avrami-Erofeev equation and the third belongs to contracting sphere (volume) equation. The corresponding pre-exponential factors ( ) are calculated simultaneously.

关键词: ammonium sulfate     decomposition kinetics     ferric oxide     thermogravimetric analysis    

on the performance and bacterial community in an expanded granular sludge bed reactor treating high-sulfate

Jun Li, Wentao Li, Gan Luo, Yan Li, Aimin Li

《环境科学与工程前沿(英文)》 2019年 第13卷 第1期 doi: 10.1007/s11783-019-1090-y

摘要:

Less than 50 mg/L nitrobenzene brought little effect on anaerobic sulfate reduction.

Kinetics of sulfate reduction under different nitrobenzene contents was studied.

Increased nitrobenzene contents greatly changed the bacterial community structure.

Genus Desulfovibrio played the key role in anaerobic sulfate reduction process.

关键词: Nitrobenzene (NB)     Sulfate-reducing bacteria (SRB)     Bacterial community     Sulfate reduction     High-throughput sequencing    

Sulfate digestion process for high purity TiO

T. A. LASHEEN

《化学科学与工程前沿(英文)》 2009年 第3卷 第2期   页码 155-160 doi: 10.1007/s11705-009-0005-z

摘要: A titania slag product of Rosetta ilmenite assaying 72% TiO is treated by the sulfate process option of the pigmentary TiO manufacture. The relevant factors of acid concentration, particle size, slag/acid ratio besides the reaction temperature, and time have been studied. After dissolving the cured mass in dilute acid and clarification, the obtained solution was subjected to hydrolysis of its titanium content. The final product was bleached under reducing conditions to redissolve the residual coloring impurities before being dewatered and calcinated. The obtained results indicated that a leaching efficiency of about 92% was realized due to the presence of some refractory components in the working slag material, namely, rutile and magnesium iron titanate. The obtained white pigment assay attained up to 99.85% TiO , while the analyzed impurities involve 77 ppm Mn and only 14 and 7 ppm of total iron and V, respectively.

关键词: titania     slag     sulfate process     pigment    

Industrial waste utilization method: producing poly-ferric sulfate (PFS) from sodium-jarosite residue

Zhongguo LI,Wenyi YUAN

《环境科学与工程前沿(英文)》 2015年 第9卷 第4期   页码 731-737 doi: 10.1007/s11783-014-0687-4

摘要: Sodium-jarosite is a type of industrial waste that results from hydrometallurgy and inorganic chemical production. The iron content of jarosite residue may be utilized to produce theoretically the ferrous materials. The difficulty in production of high quality poly-ferric sulfate (PFS) is how to remove impurities contained in jarosite residue. This paper proposes a novel method for disposing sodium-jarosite which can be used to synthesize PFS, a very important reagent for treating waste water. The method consists of a two-step leaching experimental procedures. The first step, pre-leaching process, is to remove impurity metals by strictly controlling the leaching conditions. The acid concentration of acidic water was adjusted according to the content of impurity metals in sodium-jarosite and the leaching temperature was controlled at 25°C. The second step is to decompose sodium-jarosite to provide enough ferric ions for synthesizing PFS, the concentrated sulfuric acid consumption was 0.8 mL·g sodium-jarosite and the leaching temperature was above 60°C. In the experiment, decomposing iron from sulfate sodium-jarosite can take the place of ferric martials for synthesizing PFS. Results show that the PFS synthesized from sodium-jarosite had a high poly-iron complex Fe (SO ) (OH) ·20H O. Further, the PFS product’s specifications satisfied the national standard of China.

关键词: sodium-jarosite residue     utilization     poly-ferric sulfate (PFS)    

Sodium cellulose sulfate: A promising biomaterial used for microcarriers’ designing

Qing-Xi Wu, Yi-Xin Guan, Shan-Jing Yao

《化学科学与工程前沿(英文)》 2019年 第13卷 第1期   页码 46-58 doi: 10.1007/s11705-018-1723-x

摘要: Due to a worldwide focus on sustainable materials for human health and economy services, more and more natural renewable biomass are regarded as promising materials that could replace synthetic polymers and reduce global dependence on petroleum resources. Cellulose is known as the most abundant renewable polymer in nature, varieties of cellulose-based products have been developed and have gained growing interest in recent years. In this review, a kind of water-soluble cellulose derivative, i.e., sodium cellulose sulfate (NaCS) is introduced. Details about NaCS’s physicochemical properties like solubility, biocompatibility, biodegradability, degree of substitution, etc. are systematically elaborated. And promising applications of NaCS used as biomaterials for microcarriers’ designing, such as micro-cell-carriers, micro-drug-carriers, etc., are presented.

关键词: sodium cellulose sulfate     biomaterial     physicochemical properties     microcarriers    

标题 作者 时间 类型 操作

Improving simulations of sulfate aerosols during winter haze over Northern China: the impacts of heterogeneous

Meng Gao,Gregory R. Carmichael,Yuesi Wang,Dongsheng Ji,Zirui Liu,Zifa Wang

期刊论文

Effects of two transition metal sulfate salts on secondary organic aerosol formation in toluene/NO

Biwu CHU, Jiming HAO, Junhua LI, Hideto TAKEKAWA, Kun WANG, Jingkun JIANG

期刊论文

Effects of natural zeolite and sulfate ions on the mechanical properties and microstructure of plastic

期刊论文

A time−space porosity computational model for concrete under sulfate attack

期刊论文

Biological conversion pathways of sulfate reduction ammonium oxidation in anammox consortia

Zhen Bi, Deqing Wanyan, Xiang Li, Yong Huang

期刊论文

Removal of virus aerosols by the combination of filtration and UV-C irradiation

期刊论文

Single particle analysis of ambient aerosols in Shanghai during the World Exposition, 2010: two case

Shikang TAO, Xinning WANG, Hong CHEN, Xin YANG, Mei LI, Lei LI, Zhen ZHOU

期刊论文

The solubility of cefquinome sulfate in pure and mixed solvents

Rongbao Qi,Jingkang Wang,Junxiao Ye,Hongxun Hao,Ying Bao

期刊论文

Effects of metal ions on the morphology of calcium sulfate hemihydrate whiskers by hydrothermal method

Tianjie Liu, Hao Fan, Yanxia Xu, Xingfu Song, Jianguo Yu

期刊论文

PICRUSt2 functionally predicts organic compounds degradation and sulfate reduction pathways in an acidogenic

期刊论文

Thermal decomposition mechanism of ammonium sulfate catalyzed by ferric oxide

Xingfu SONG, Jingcai ZHAO, Yunzhao LI, Ze SUN, Jianguo YU

期刊论文

on the performance and bacterial community in an expanded granular sludge bed reactor treating high-sulfate

Jun Li, Wentao Li, Gan Luo, Yan Li, Aimin Li

期刊论文

Sulfate digestion process for high purity TiO

T. A. LASHEEN

期刊论文

Industrial waste utilization method: producing poly-ferric sulfate (PFS) from sodium-jarosite residue

Zhongguo LI,Wenyi YUAN

期刊论文

Sodium cellulose sulfate: A promising biomaterial used for microcarriers’ designing

Qing-Xi Wu, Yi-Xin Guan, Shan-Jing Yao

期刊论文