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A Study of the Functional Mechanism of Petrochemical Engineering Construction Project Management

Ji-ming Wang

《工程管理前沿（英文）》 2014年 第1卷 第2期   页码 129-139 doi: 10.15302/J-FEM-2014020

摘要： This paper, proceeding from the project construction process, the management mode and the implementation way, makes an in-depth study of the environmental characteristics and the managerial elements of petrochemical engineering construction project, revealing the inherent laws, establishing a theoretical model, and proposing a theory of the mechanisms of construction project management; and presents profound revelations found for construction project management in petrochemical engineering in seven aspects, which can play a guiding role in improving the managerial performance of petrochemical construction project. The theory established proposes that: The construction project management in petrochemical engineering is a complex systematic process, formed of 5 phases and 55 sub-processes of management, and exposed to many factors of influence; the environmental characteristics and managerial elements exercise positive impacts on managerial performance, but different factors have different impacts and act in different ways on managerial performance; the managerial elements of petrochemical engineering construction project are tiered, transferable, systematic and quantifiable, and the role of managerial elements in the managerial performance can be systematically integrated, quantitatively explained and transferred in a multi-level way.

关键词： petrochemical engineering     construction project     project management     functional mechanism    

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A density functional theory study on the mechanism of Dimethyl ether carbonylation over heteropolyacids

Kai Cai, Ying Li, Hongbao Shen, Zaizhe Cheng, Shouying Huang, Yue Wang, Xinbin Ma

《化学科学与工程前沿（英文）》 2021年 第15卷 第2期   页码 319-329 doi: 10.1007/s11705-020-1957-2

摘要： Dimethyl ether (DME) carbonylation is considered as a key step for a promising route to produce ethanol from syngas. Heteropolyacids (HPAs) are proved to be efficient catalysts for DME carbonylation. In this work, the reaction mechanism of DME carbonylation was studied theoretically by using density functional theory calculations on two typical HPA models (HPW, HSiW). The whole process consists of three stages: DME dissociative adsorption, insertion of CO into methoxyl group and formation of product methyl acetate. The activation barriers of all possible elementary steps, especially two possible paths for CO insertion were calculated to obtain the most favorable reaction mechanism and rate-limiting step. Furthermore, the effect of the acid strength of Brønsted acid sites on reactivity was studied by comparing the activation barriers over HPW and HSiW with different acid strength, which was determined by calculating the deprotonation energy, Mulliken population analyses and adsorption energies of pyridine.

关键词： dimethyl ether     carbonylation     mechanism     heteropolyacids     density functional theory    

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Regulatory mechanism and functional analysis of

null

《医学前沿（英文）》 2017年 第11卷 第1期   页码 87-96 doi: 10.1007/s11684-016-0469-4

摘要：

S100A9, a calcium-binding protein, participates in the inflammatory process and development of various tumors, thus attracting much attention in the field of cancer biology. This study aimed to investigate the regulatory mechanism of and its function involvement in APL. We used real-time quantitative PCR to determine whether PML/RARα affects the expression of in NB4 and PR9 cells upon ATRA treatment. ChIP-based PCR and dual-luciferase reporter assay system were used to detect how PML/RARα and PU.1 regulate promoter activity. CCK-8 assay and flow cytometry were employed to observe the viability and apoptosis of NB4 cells when was overexpressed. Results showed that was an ATRA-responsive gene, and PML/RARα was necessary for the ATRA-induced expression of in APL cells. In addition, PU.1 could bind to the promoter of , especially when treated with ATRA in NB4 cells, and promote its activity. More importantly, overexpression of induced the apoptosis of NB4 cells and inhibited cell growth. Collectively, our data indicated that PML/RARα and PU.1 were necessary for the ATRA-induced expression of in APL cells. Furthermore, promoted apoptosis in APL cells and affected cell growth.

关键词： S100A9 S100A9     PU.1     PML/RARα     ATRA     APL    

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Theoretical study on the mechanism of sulfur migration to gas in the pyrolysis of benzothiophene

《化学科学与工程前沿（英文）》 2023年 第17卷 第3期   页码 334-346 doi: 10.1007/s11705-022-2209-4

摘要： The release and control of sulfur species in the pyrolysis of fossil fuels and solid wastes have attracted attention worldwide. Particularly, thiophene derivatives are important intermediates for the sulfur gas release from organic sulfur, but the underlying migration mechanisms remain unclear. Herein, the mechanism of sulfur migration during the release of sulfur-containing radicals in benzothiophene pyrolysis was explored through quantum chemistry modeling. The C1-to-C2 H-transfer has the lowest energy barrier of 269.9 kJ·mol–1 and the highest rate constant at low temperatures, while the elevated temperature is beneficial for C−S bond homolysis. 2-Ethynylbenzenethiol is the key intermediate for the formation of S and SH radicals with the overall energy barriers of 408.0 and 498.7 kJ·mol–1 in favorable pathways. The generation of CS radicals is relatively difficult because of the high energy barrier (551.8 kJ·mol–1). However, it can be significantly promoted by high temperatures, where the rate constant exceeds that for S radical generation above 930 °C. Consequently, the strong competitiveness of S and SH radicals results in abundant H2S during benzothiophene pyrolysis, and the high temperature is more beneficial for CS2 generation from CS radicals. This study lays a foundation for elucidating sulfur migration mechanisms and furthering the development of pyrolysis techniques.

关键词： benzothiophene     sulfur migration     pyrolysis     density functional theory    

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Mechanism of ethanol/water reverse separation through a functional graphene membrane: a molecular simulation

《化学科学与工程前沿（英文）》 2023年 第17卷 第3期   页码 347-357 doi: 10.1007/s11705-022-2246-z

摘要： Reverse-selective membranes have attracted considerable interest for bioethanol production. However, to date, the reverse-separation performance of ethanol/water is poor and the separation mechanism is unclear. Graphene-based membranes with tunable apertures and functional groups have shown substantial potential for use in molecular separation. Using molecular dynamics simulations, for the first time, we reveal two-way selectivity in ethanol/water separation through functional graphene membranes. Pristine graphene (PG) exhibits reverse-selective behavior with higher ethanol fluxes than water, resulting from the preferential adsorption for ethanol. Color flow mappings show that this ethanol-permselective process is initiated by the presence of ethanol-enriched and water-barren pores; this has not been reported in previous studies. In contrast, water molecules are preferred for hydroxylated graphene membranes because of the synergistic effects of molecular sieving and functional-group attraction. A simulation of the operando condition shows that the PG membrane with an aperture size of 3.8 Å achieves good separation performance, with an ethanol/water separation factor of 34 and a flux value of 69.3 kg∙m‒2∙h‒1∙bar‒1. This study provides new insights into the reverse-selective mechanism of porous graphene membranes and a new avenue for efficient biofuel production.

关键词： reverse separation     graphene membrane     ethanol/water separation     molecular simulation    

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Heterogeneous reaction mechanism of gaseous HNO

Nan ZHAO,Qingzhu ZHANG,Wenxing WANG

《环境科学与工程前沿（英文）》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0836-z

摘要： We studied the heterogeneous reaction mechanism of gaseous HNO with solid NaCl. HCl is released from heterogeneous reactions between gaseous HNO and solid NaCl. Water molecules induce surface reconstruction of NaCl to facilitate the reaction. Sea salt particles containing NaCl are among the most abundant particulate masses in coastal atmosphere. Reactions involving sea salt particles potentially generate Cl radicals, which are released into coastal atmosphere. Cl radicals play an important role in the nitrogen and O cycles, sulfur chemistry and particle formation in the troposphere of the polluted coastal regions. This paper aimed at the heterogeneous reaction between gaseous HNO and solid NaCl. The mechanism was investigated by density functional theory (DFT). The results imply that water molecules induce the surface reconstruction, which is essential for the heterogeneous reaction. The surface reconstruction on the defective (710) surface has a barrier of 10.24 kcal·mol and is endothermic by 9.69 kcal·mol , whereas the reconstruction on the clean (100) surface has a barrier of 18.46 kcal·mol and is endothermic by 12.96 kcal·mol . The surface reconstruction involved in water-adsorbed (710) surface is more energetically favorable. In comparison, water molecules adsorbed on NaCl (100) surface likely undergo water diffusion or desorption. Further, it reveals that the coordination number of the Cl is reduced after the surface reconstruction, which assists Cl to accept the proton from HNO . HCl is released from heterogeneous reactions between gaseous HNO and solid NaCl and can react with OH free radicals to produce atomic Cl radicals. The results will offer further insights into the impact of gaseous HNO on the air quality of the coastal areas.

关键词： Seasalt particles     NaCl     HNO3     Heterogeneous reaction     Reaction mechanism     Density functional theory    

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Seed-induced synthesis of functional MFI zeolite materials: Method development, crystallization mechanisms

Zhaoqi Ye, Hongbin Zhang, Yahong Zhang, Yi Tang

《化学科学与工程前沿（英文）》 2020年 第14卷 第2期   页码 143-158 doi: 10.1007/s11705-019-1852-x

摘要： As an important zeolite material, MFI zeolites, as well as their controllable synthesis, are of great interest in both basic and applied science. Among the developed synthetic approaches, the seed-induced method has gradually evolved into a facile, low-cost, and even green alternative to give zeolites the desirable physicochemical properties. In this review, we briefly summarize the development of seed-induced syntheses of diverse functional MFI zeolites, where the “living” seed crystals not only direct the formation of zeolitic framework but also function as special “templates” or “units” to fine-tune the zeolite materials with diverse sizes, shapes, compositions, morphologies and pore structures. Moreover, on the basis of their structural features and crystallization behaviors in seed-induced synthesis, we reveal the roles of seeds and discuss the related crystallization mechanisms including both classical and non-classical pathways. We also want to guide readers to investigate the structure-performance relationships between these functional MFI zeolite catalysts and suitable catalytic reactions.

关键词： seed-induced synthesis     MFI zeolite     synthesis mechanism     catalytic property    

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Mechanism of methanol decomposition on the Pd/WC(0001) surface unveiled by first-principles calculations

Jinhua Zhang, Yuanbin She

《化学科学与工程前沿（英文）》 2020年 第14卷 第6期   页码 1052-1064 doi: 10.1007/s11705-019-1908-y

摘要： In this study, the decomposition of methanol into the CO and H species on the Pd/tungsten carbide (WC)(0001) surface is systematically investigated using periodic density functional theory (DFT) calculations. The possible reaction pathways and intermediates are determined. The results reveal that saturated molecules, i.e., methanol and formaldehyde, adsorb weakly on the Pd/WC(0001) surface. Both CO and H prefer three-fold sites, with adsorption energies of ‒1.51 and ‒2.67 eV, respectively. On the other hand, CH O stably binds at three-fold and bridge sites, with an adsorption energy of ‒2.58 eV. However, most of the other intermediates tend to adsorb to the surface with the carbon and oxygen atoms in their sp and hydroxyl-like configurations, respectively. Hence, the C atom of CH OH preferentially attaches to the top sites, CHOH and CH O adsorb at the bridge sites, while COH and CHO occupy the three-fold sites. The DFT calculations indicate that the rupture of the initial C–H bond promotes the decomposition of CH OH and CH OH, whereas in the case of CHOH, O–H bond scission is favored over the C–H bond rupture. Thus, the most probable methanol decomposition pathway on the Pd/WC(0001) surface is CH OH → CH OH → -CHOH → CHO → CO. The present study demonstrates that the synergistic effect of WC (as carrier) and Pd (as catalyst) alters the CH OH decomposition pathway and reduces the noble metal utilization.

关键词： density functional theory     methanol     direct methanol fuel cells     WC(0001)-supported Pd monolayer     decomposition mechanism    

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Dual-functional sites for synergistic adsorption of Cr(VI) and Sb(V) by polyaniline-TiO hydrate: Adsorption

《环境科学与工程前沿（英文）》 2022年 第16卷 第8期 doi: 10.1007/s11783-022-1526-7

摘要：

• PANI/Ti(OH)n(4–n)+ exhibited excellent adsorption capacity and reusability.

关键词： Polyaniline/TiO2     Chromium     Antimony     Adsorption     Desorption     Mechanism    

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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    

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Mechanism insight into the formation of HS from thiophene pyrolysis: A theoretical study

《环境科学与工程前沿（英文）》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1404-8

摘要：

• Possible formation pathways of H2S were revealed in thiophene pyrolysis.

关键词： Density functional theory     Waste rubber     Thiophene     H2S     Pyrolysis    

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Development and applications of functional gene microarrays in the analysis of the functional diversity

Zhili HE, Joy D. VAN NOSTRAND, Ye DENG, Jizhong ZHOU

《环境科学与工程前沿（英文）》 2011年 第5卷 第1期   页码 1-20 doi: 10.1007/s11783-011-0301-y

摘要： Functional gene arrays (FGAs) are a special type of microarrays containing probes for key genes involved in microbial functional processes, such as biogeochemical cycling of carbon, nitrogen, sulfur, phosphorus, and metals, biodegradation of environmental contaminants, energy processing, and stress responses. GeoChips are considered as the most comprehensive FGAs. Experimentally established probe design criteria and a computational pipeline integrating sequence retrieval, probe design and verification, array construction, data analysis, and automatic update are used to develop the GeoChip technology. GeoChip has been systematically evaluated and demonstrated to be a powerful tool for rapid, specific, sensitive, and quantitative analysis of microbial communities in a high-throughput manner. Several generations of GeoChip have been developed and applied to investigate the functional diversity, composition, structure, function, and dynamics of a variety of microbial communities from different habitats, such as water, soil, marine, bioreactor, human microbiome, and extreme ecosystems. GeoChip is able to address fundamental questions related to global change, bioenergy, bioremediation, agricultural operation, land use, human health, environmental restoration, and ecological theories and to link the microbial community structure to environmental factors and ecosystem functioning.

关键词： functional gene arrays (FGAs)     GeoChip     microbial communities     functional diversity/composition/structure     environmental factor     ecosystem functioning    

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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    

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Fluorescent probes and functional materials for biomedical applications

《化学科学与工程前沿（英文）》 2022年 第16卷 第10期   页码 1425-1437 doi: 10.1007/s11705-022-2163-1

摘要： Due to their simplicity in preparation, sensitivity and selectivity, fluorescent probes have become the analytical tool of choice in a wide range of research and industrial fields, facilitating the rapid detection of chemical substances of interest as well as the study of important physiological and pathological processes at the cellular level. In addition, many long-wavelength fluorescent probes developed have also proven applicable for in vivo biomedical applications including fluorescence-guided disease diagnosis and theranostics (e.g., fluorogenic prodrugs). Impressive progresses have been made in the development of sensing agents and materials for the detection of ions, organic small molecules, and biomacromolecules including enzymes, DNAs/RNAs, lipids, and carbohydrates that play crucial roles in biological and disease-relevant events. Here, we highlight examples of fluorescent probes and functional materials for biological applications selected from the special issues “Fluorescent Probes” and “Molecular Sensors and Logic Gates” recently published in this journal, offering insights into the future development of powerful fluorescence-based chemical tools for basic biological studies and clinical translation.

关键词： fluorescent probes     imaging     cell     biomedicine     biomolecules    

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Temporal dimension and water quality control in an emission trading scheme based on water environmental functional

Zhaoxing HAN, Zhenyao SHEN, Yongwei GONG, Qian HONG

《环境科学与工程前沿（英文）》 2011年 第5卷 第1期   页码 119-129 doi: 10.1007/s11783-011-0272-z

摘要： Emission trading is one of the most effective alternatives to controlling water pollution. Water environmental functional zone (WEFZ) is used to determine the water quality standard and identify the zone boundary for each river or reach. In this study, a new emission trading scheme was addressed based on WEFZ, accounting for both the temporal dimension and water quality control. A temporal factor of emission trading was proposed based on variations in the environmental capacity within a year by dividing the year into three periods, including high, normal, and low periods of environmental capacity. During each period, emission trading was implemented exclusively. A water quality-control scheme was suggested based on the water quality requirement in the water functional zone, in which the water quality at the downstream boundary of the zone was required to meet the water standard following auto-purification in the stream. Two methods of calculating water quality control are addressed for point-source pollution and non-point-source pollution. The calculated temporal dimension and water quality control were located in Dongxi River of the Daning Watershed in the Three Gorges Watershed. The high period was during June, July, and August, the normal period was during April, May, September, and October, and the low period was during January, February, March, November, and December. The results from the water quality calculation demonstrated that the discharge of point-source and non-point-source pollutions led to an excess of common contaminants at the downstream boundary of WEFZ. The temporal and spatial factors above should be incorporated into the emission trading scheme based on WEFZ.

关键词： emission trading     water functional zone     water quality control    

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标题 作者 时间 类型 操作

A Study of the Functional Mechanism of Petrochemical Engineering Construction Project Management

Ji-ming Wang

期刊论文

A density functional theory study on the mechanism of Dimethyl ether carbonylation over heteropolyacids

Kai Cai, Ying Li, Hongbao Shen, Zaizhe Cheng, Shouying Huang, Yue Wang, Xinbin Ma

期刊论文

Regulatory mechanism and functional analysis of

null

期刊论文

Theoretical study on the mechanism of sulfur migration to gas in the pyrolysis of benzothiophene

期刊论文

Mechanism of ethanol/water reverse separation through a functional graphene membrane: a molecular simulation

期刊论文

Heterogeneous reaction mechanism of gaseous HNO

Nan ZHAO,Qingzhu ZHANG,Wenxing WANG

期刊论文

Seed-induced synthesis of functional MFI zeolite materials: Method development, crystallization mechanisms

Zhaoqi Ye, Hongbin Zhang, Yahong Zhang, Yi Tang

期刊论文

Mechanism of methanol decomposition on the Pd/WC(0001) surface unveiled by first-principles calculations

Jinhua Zhang, Yuanbin She

期刊论文

Dual-functional sites for synergistic adsorption of Cr(VI) and Sb(V) by polyaniline-TiO hydrate: Adsorption

期刊论文

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

期刊论文

Mechanism insight into the formation of HS from thiophene pyrolysis: A theoretical study

期刊论文

Development and applications of functional gene microarrays in the analysis of the functional diversity

Zhili HE, Joy D. VAN NOSTRAND, Ye DENG, Jizhong ZHOU

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

Fluorescent probes and functional materials for biomedical applications

期刊论文

Temporal dimension and water quality control in an emission trading scheme based on water environmental functional

Zhaoxing HAN, Zhenyao SHEN, Yongwei GONG, Qian HONG

期刊论文