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Performance and mechanism of carbamazepine removal by FeS-SO process: experimental investigation and DFTcalculations

《环境科学与工程前沿(英文)》 2023年 第17卷 第9期 doi: 10.1007/s11783-023-1713-1

摘要:

● Synergistic removal of carbamazepine (CBZ) was obtained in the FeS-S2O82– process.

关键词: FeS     S2O82–     Carbamazepine     DFT calculations     Degradation routes    

Theoretical insights into influence of additives on sulfamethoxazole crystal growth kinetics and mechanisms

《化学科学与工程前沿(英文)》 2023年 第17卷 第10期   页码 1503-1515 doi: 10.1007/s11705-022-2294-4

摘要: In this work, the influence of the initial chemical potential gradient, stirring speed, and polymer type on sulfamethoxazole (SMX) crystal growth kinetics was systematically investigated through density functional theory (DFT) calculations, experimental measurements and the two-step chemical potential gradient model. To investigate the influence of different conditions on the thermodynamic driving force of SMX crystal growth, SMX solubilities in different polymer solutions were studied. Four model polymers effectively improved SMX solubility. It was further found that polyvinylpyrrolidone (PVP) and hydroxypropyl methyl cellulose (HPMC) played a crucial role in inhibiting SMX crystal growth. However, polyethylene glycol (PEG) promoted SMX crystal growth. The effect of the polymer on the crystal growth mechanisms of SMX was further analyzed by the two-step chemical potential gradient model. In the system containing PEG 6000, crystal growth is dominated by the surface reaction. However, in the system containing PEG 20000, crystal growth is dominated by both the surface reaction and diffusion. In addition, DFT calculations results showed that HPMC and PVP could form strong and stable binding energies with SMX, indicating that PVP and HPMC had the potential ability to inhibit SMX crystal growth.

关键词: insoluble drugs     polymer     inhibition crystallization     crystal growth kinetics     DFT calculations    

Mass and heat balance calculations and economic evaluation of an innovative biomass pyrolysis project

Quanyuan WEI, Yongshui QU, Tianwei TAN

《化学科学与工程前沿(英文)》 2011年 第5卷 第3期   页码 355-361 doi: 10.1007/s11705-010-0567-9

摘要: Biomass can be converted into flammable gas, charcoal, wood vinegar, wood tar oil and noncombustible materials with thermo-chemical pyrolysis reactions. Many factors influence these processes, such as the properties of the raw materials, and temperature control and these will affect the products that are produced. Based on the data from a straw pyrolysis demonstration project, the mass and heat balance of the biomass pyrolysis process were analyzed. The statistical product and service solutions (SPSS) statistical method was used to analyze the data which were monitored on-site. A cost-benefit analysis was then used to study the viability of commercializing the project. The analysis included net present value, internal rate of return and investment payback period. These results showed that the straw pyrolysis project has little risk, and will produce remarkable economic benefits.

关键词: mass balance     heat balance     biomass pyrolysis     economic benefit    

Predictive calculations of gas solubility and permeability in glassy polymeric membranes: An overview

Matteo Minelli, Maria Grazia De Angelis, Giulio C. Sarti

《化学科学与工程前沿(英文)》 2017年 第11卷 第3期   页码 405-413 doi: 10.1007/s11705-017-1615-5

摘要: The possibility to evaluate in a predictive way the relevant transport properties of low molecular weight species, both gases and vapors, in glassy polymeric membranes is inspected in detail, with particular attention to the methods recently developed based on solid thermodynamic basis. The solubility of pure and mixed gases, diffusivity and permeability of single gases in polymer glasses are examined, considering in particular poly(2,6-dimethyl-1,4-phenylene oxide) as a relevant test case. The procedure clearly indicates what are the relevant physical properties of the polymer matrix and of the penetrants required by the calculations, which can be obtained experimentally through independent measurements. For gas and vapor solubility, the comparison with direct experimental data for mixed gases points out also the ability to account for the significant variations that solubility-selectivity experiences upon variations of pressure and/or feed composition. For gas and vapor permeability, the comparison with direct experimental data shows the possibility to account for the various different trends observed experimentally as penetrant pressure is increased, including the so-called plasticization behavior. The procedure followed for permeability calculations leads also to clear correlations between permeability and physical properties of both polymer and penetrant, based on which pure predictive calculations are reliably made.

关键词: solubility     permeability     glassy polymers     NELF model     diffusion    

ternary transition temperature mixture (deep eutectic analogues) for CO absorption: Characterizations and DFT

《环境科学与工程前沿(英文)》 2022年 第16卷 第7期 doi: 10.1007/s11783-021-1500-9

摘要:

•Addition of hindered amine increased thermal stability and viscosity of TTTM.

关键词: Ternary transition-temperature mixture     FT-IR and thermal stability analysis     Viscosity and correlation study     Eyring’s absolute rate theory     CO2 solubility     Density functional theory (DFT).    

Experimental and DFT insights into nitrogen and sulfur co-doped carbon nanotubes for effective desulfurization

《环境科学与工程前沿(英文)》 2021年 第15卷 第5期 doi: 10.1007/s11783-021-1397-3

摘要:

• Synthesis of NS-CNTS is used in a high desulfurization performance.

关键词: Dibenzothiophene (DBT)     Tertiary methyl mercaptan     Adsorption     Carbon nano tube (CNT)     Desulfurization     Doping    

Synthesis, insecticidal activities and DFT study of pyrimidin-4-amine derivatives containing the 1,2,4

《化学科学与工程前沿(英文)》 2022年 第16卷 第7期   页码 1090-1100 doi: 10.1007/s11705-021-2091-5

摘要: Twenty six novel pyrimidin-4-amine derivatives containing the 1,2,4-oxadiazole motif were synthesized. Their chemical structures were confirmed by 1H nuclear magnetic resonance (NMR), 13C NMR, and high-resolution mass spectrography. The insecticidal activity results indicated that some of them possessed excellent insecticidal activity (100%) against Mythimna separate, especially for compounds 6d, 6f, 6o, 6w, 6y and 6z. These compounds exhibited no activity against the insects Aphis medicagini and Tetranychus cinnabarinus. The structure- insecticidal activity relationships are discussed. Density functional theory analysis can potentially be used to design more active compounds. These results provide useful insecticide design information for further optimization.

关键词: synthesis     pyrimidin-4-amine derivatives     1     2     4-oxadiazole     insecticidal activity     structure-activity relationship    

Electronic and mechanical responses of two-dimensional HfS

Mohammad SALAVATI

《结构与土木工程前沿(英文)》 2019年 第13卷 第2期   页码 486-494 doi: 10.1007/s11709-018-0491-5

摘要: During the last decade, numerous high-quality two-dimensional (2D) materials with semiconducting electronic character have been synthesized. Recent experimental study (Sci. Adv. 2017;3: e1700481) nevertheless confirmed that 2D ZrSe and HfSe are among the best candidates to replace the silicon in nanoelectronics owing to their moderate band-gap. We accordingly conducted first-principles calculations to explore the mechanical and electronic responses of not only ZrSe and HfSe , but also ZrS and HfS in their single-layer and free-standing form. We particularly studied the possibility of engineering of the electronic properties of these attractive 2D materials using the biaxial or uniaxial tensile loadings. The comprehensive insight provided concerning the intrinsic properties of HfS , HfSe , ZrS , and ZrSe can be useful for their future applications in nanodevices.

关键词: 2D materials     mechanical     electronic     DFT    

fluorescence properties of 14 selected toxic single-ring aromatic compounds in water: Experimental and DFT

Muhammad Farooq Saleem Khan, Jing Wu, Cheng Cheng, Mona Akbar, Chuanyang Liu, Bo Liu, Jian Shen, Yu Xin

《环境科学与工程前沿(英文)》 2020年 第14卷 第3期 doi: 10.1007/s11783-020-1219-z

摘要: The fluorescence peak location of 14 compounds interpreted at protein-like region. The p-electron system inside aromatic ring contributes to the fluorophore region. Functional group variation effects the emission spectra. Decrease in quantum yield and increase in DE is due to atomic weight F>Cl>Br>I. Theoretically results are in line with experimental ones. Various single-ring aromatic compounds in water sources are of great concern due to its hazardous impact on the environment and human health. The fluorescence excitation-emission matrix (EEMs) spectrophotometry is a useful method to identify organic pollutants in water. This study provides a detailed insight into the fluorescence properties of the 14 selected toxic single-ring aromatic compounds by experimental and theoretical analysis. The theoretical analysis were done with Time-Dependent Density Functional Theory (TD-DFT) and B3LYP/6-31G (d,p) basis set, whereas, Polarizable Continuum Model (PCM) was used to consider water as solvent. The selected compounds displayed their own specific excitation-emission (Ex/Em) wavelengths region, at Ex<280 nm and Em<340 nm, respectively. Whereas the theoretical Ex/Em was observed as, Ex at 240 nm–260 nm and Em at 255 nm–300 nm. Aniline as a strong aromatic base has longer Em (340 nm) than alkyl, carbonyl, and halogens substituted benzenes. The lone pair of electrons at amide substituent serves as a p-electron contributor into the aromatic ring, hence increasing the stability and transition energy, which results in longer emission and low quantum yield for the aniline. The fluorescence of halogenated benzenes illustrates an increase in the HOMO-LUMO energy gap and a decrease in quantum yield associated with atomic size (F>Cl>Br>I). In this study the theoretical results are in line with experimental ones. The understanding of fluorescence and photophysical properties are of great importance in the identification of these compounds in the water.

关键词: Fluorescence     Photophysical properties     Effect of the substituent     Toxic aromatic compounds    

Characterization of random stress fields obtained from polycrystalline aggregate calculations using multi-scale

Bruno SUDRET,Hung Xuan DANG,Marc BERVEILLER,Asmahana ZEGHADI,Thierry YALAMAS

《结构与土木工程前沿(英文)》 2015年 第9卷 第2期   页码 121-140 doi: 10.1007/s11709-015-0290-1

摘要: The spatial variability of stress fields resulting from polycrystalline aggregate calculations involving random grain geometry and crystal orientations is investigated. A periodogram-based method is proposed to identify the properties of homogeneous Gaussian random fields (power spectral density and related covariance structure). Based on a set of finite element polycrystalline aggregate calculations the properties of the maximal principal stress field are identified. Two cases are considered, using either a fixed or random grain geometry. The stability of the method w.r.t the number of samples and the load level (up to 3.5% macroscopic deformation) is investigated.

关键词: polycrystalline aggregates     crystal plasticity     random fields     spatial variability     correlation structure    

Ammonia adsorption on graphene and graphene oxide: a first-principles study

Yue PENG, Junhua LI

《环境科学与工程前沿(英文)》 2013年 第7卷 第3期   页码 403-411 doi: 10.1007/s11783-013-0491-6

摘要: Motivated by the recent realization of graphene sensor to detect gas molecules that are harmful to the environment, the ammonia adsorption on graphene or graphene oxide (GO) was investigated using first-principles calculation. The optimal adsorption and orientation of the NH molecules on the graphene surfaces were determined, and the adsorption energies ( ) as well as the Mulliken charge transfers of NH were calculated. The for the graphene are small and seem to be independent of the sites and orientations. The surface epoxy or hydroxyl groups can promote the adsorption of NH on the GO; the enhancement of the for the hydroxyl groups is greater than that for the epoxy groups on the surface. The charge transfers from the molecule to the surfaces also exhibit the same trend. The Br?nsted acid sites and Lewis acid sites could stably exist on the GO with surface hydroxyl groups and on the basal, respectively.

关键词: graphene oxide     first-principles calculations     NH3 adsorption    

New insights into mercury removal mechanism on CeO

Ling Li, Yu He, Xia Lu

《环境科学与工程前沿(英文)》 2018年 第12卷 第2期 doi: 10.1007/s11783-018-1007-1

摘要: First-principles calculations were performed to investigate the mechanism of Hg adsorption and oxidation on CeO (111). Surface oxygen activated by the reduction of Ce to Ce was vital to Hg adsorption and oxidation processes. Hg was fully oxidized by the surface lattice oxygen on CeO (111), without using any other oxidizing agents. HCl could dissociate and react with the Hg adatom on CeO (111) to form adsorbed Hg–Cl or Cl–Hg–Cl groups, which promoted the desorption of oxidized Hg and prevented CeO catalyst deactivation. In contrast, O–H and H–O–H groups formed during HCl adsorption consumed the active surface oxygen and prohibited Hg oxidation. The consumed surface oxygen was replenished by adding O into the flue gas. We proposed that oxidized Hg desorption and maintenance of sufficient active surface oxygen were the rate-determining steps of Hg removal on CeO -based catalysts. We believe that our thorough understanding and new insights into the mechanism of the Hg removal process will help provide guidelines for developing novel CeO -based catalysts and enhance the Hg removal efficiency.

关键词: Elemental mercury removal     Surface adsorption     Ceria     First-principles calculations    

Regulation of radicals by hydrogen-donor solvent in direct coal liquefaction

《化学科学与工程前沿(英文)》 2022年 第16卷 第12期   页码 1689-1699 doi: 10.1007/s11705-022-2186-7

摘要: Radicals are important intermediates in direct coal liquefaction. Certain radicals can cause the cleavage of chemical bonds. At high temperatures, radical fragments can be produced by the splitting of large organic molecules, which can break strong chemical bonds through the induction pyrolysis of radicals. The reaction between the formation and annihilation of coal radical fragments and the effect of hydrogen-donor solvents on the radical fragments are discussed in lignite hydrogenolysis. Using the hydroxyl and ether bonds as indicators, the effects of different radicals on the cleavage of chemical bond were investigated employing density functional theory calculations and lignite hydrogenolysis experiments. Results showed that the adjustment of the coal radical fragments could be made by the addition of hydrogen-donor solvents. Results showed that the transition from coal radical fragment to H radical leads to the variation of product distribution. The synergistic mechanism of hydrogen supply and hydrogenolysis of hydrogen-donor solvent was proposed.

关键词: direct coal liquefaction     hydrogen-donor solvent     induced pyrolysis     radical mechanism     density functional theory calculations    

Fluorescent properties and

Hong GAO,Jie SONG,Shibin SHANG,Zhanqian SONG

《农业科学与工程前沿(英文)》 2017年 第4卷 第1期   页码 106-115 doi: 10.15302/J-FASE-2017133

摘要: A series of dehydroabietic acid-based diarylamines have been synthesized in order to investigate their fluorescent properties, photostability, cell toxicity and fluorescence imaging. The geometries as well as their molecular properties were optimized at the B3LYP/6-31G* level using Gaussian 03. The results indicate that molecular geometry, HOMO and LUMO energies, and energy gaps are important to predict absorption and fluorescent properties. Five of the compounds can be effectively taken up by human cervical carcinoma, human hepatocellular carcinoma SMMC-7721, human gastric cancer SGC-7901 and human lung adenocarcinoma A549 cells and strong blue fluorescent signals are detected in these cells. These compounds are potential candidates for fluorescent probes in biological diagnosis.

关键词: dehydroabietic acid-based diarylamine     DFT study     fluorescent probe     in vitro imaging    

A combined experimental and theoretical study of micronized coal reburning

Hai ZHANG, Jiaxun LIU, Jun SHEN, Xiumin JIANG

《能源前沿(英文)》 2013年 第7卷 第1期   页码 119-126 doi: 10.1007/s11708-012-0226-6

摘要: Micronized coal reburning (MCR) can not only reduce carbon in fly ash but also reduce NO emissions as compared to the conventional coal reburning. However, it has two major kinetic barriers in minimizing NO emission. The first is the conversion of NO into hydrogen cyanide (HCN) by conjunction with various hydrocarbon fragments. The second is the oxidation of HCN by association with oxygen-containing groups. To elucidate the advantages of MCR, a combination of Diffuse Reflection Fourier Transform Infrared (FTIR) experimental studies with Density Functional Theory (DFT) theoretical calculations is conducted in terms of the second kinetic barrier. FTIR studies based on Chinese Tiefa coal show that there are five hydroxide groups such as OH-π, OH-N, OH-OR , self-associated OH and free OH. The hydroxide groups increase as the mean particle size decreases expect for free OH. DFT calculations at the B3LYP/6-31 G(d) level indicate that HCN can be oxidized by hydroxide groups in three paths, HCN+OH→HOCN+H (path 1), HCN+OH→HNCO+H (path 2), and HCN+OH→CN+H O (path 3). The rate limiting steps for path 1, path 2 and path 3 are IM2→P1+H (170.66 kJ/mol activated energy), IM1→IM3 (231.04 kJ/mol activated energy), and R1+OH→P3+H O (97.14 kJ/mol activated energy), respectively. The present study of MCR will provide insight into its lower NO emission and guidance for further studies.

关键词: hydroxyl radicals     Fourier transform infrared spectroscopy (FTIR)     density functional theory (DFT)     homogeneous reaction mechanism     NOx    

标题 作者 时间 类型 操作

Performance and mechanism of carbamazepine removal by FeS-SO process: experimental investigation and DFTcalculations

期刊论文

Theoretical insights into influence of additives on sulfamethoxazole crystal growth kinetics and mechanisms

期刊论文

Mass and heat balance calculations and economic evaluation of an innovative biomass pyrolysis project

Quanyuan WEI, Yongshui QU, Tianwei TAN

期刊论文

Predictive calculations of gas solubility and permeability in glassy polymeric membranes: An overview

Matteo Minelli, Maria Grazia De Angelis, Giulio C. Sarti

期刊论文

ternary transition temperature mixture (deep eutectic analogues) for CO absorption: Characterizations and DFT

期刊论文

Experimental and DFT insights into nitrogen and sulfur co-doped carbon nanotubes for effective desulfurization

期刊论文

Synthesis, insecticidal activities and DFT study of pyrimidin-4-amine derivatives containing the 1,2,4

期刊论文

Electronic and mechanical responses of two-dimensional HfS

Mohammad SALAVATI

期刊论文

fluorescence properties of 14 selected toxic single-ring aromatic compounds in water: Experimental and DFT

Muhammad Farooq Saleem Khan, Jing Wu, Cheng Cheng, Mona Akbar, Chuanyang Liu, Bo Liu, Jian Shen, Yu Xin

期刊论文

Characterization of random stress fields obtained from polycrystalline aggregate calculations using multi-scale

Bruno SUDRET,Hung Xuan DANG,Marc BERVEILLER,Asmahana ZEGHADI,Thierry YALAMAS

期刊论文

Ammonia adsorption on graphene and graphene oxide: a first-principles study

Yue PENG, Junhua LI

期刊论文

New insights into mercury removal mechanism on CeO

Ling Li, Yu He, Xia Lu

期刊论文

Regulation of radicals by hydrogen-donor solvent in direct coal liquefaction

期刊论文

Fluorescent properties and

Hong GAO,Jie SONG,Shibin SHANG,Zhanqian SONG

期刊论文

A combined experimental and theoretical study of micronized coal reburning

Hai ZHANG, Jiaxun LIU, Jun SHEN, Xiumin JIANG

期刊论文