With the increasing public consciousness on environmental issues, chemical products and process designs require simultaneous satisfaction and compromise of environmental and economical requirements. To fulfill the two...With the increasing public consciousness on environmental issues, chemical products and process designs require simultaneous satisfaction and compromise of environmental and economical requirements. To fulfill the two conflicting while complementary objectives, a systematic approach for life cycle design of a chemical product is proposed in this article. Multiattribute decision-making is adopted in a trade-off consideration of both technical economical evaluation and environmental impacts assessment using the analytic hierarchy process (AHP) approach. On the basis of an evaluation of the relative importance of the criteria multicriteria decision making is performed. In this study, an AHP model is used to derive single a criteria score by analyzing the environmental impact and life cycle cost of a product, respectively. And a fluctuant weight analysis is put forth to calculate the integrated index of the product to enable products to be ranked or selected intuitionally and conveniently. The proposed AHP model has been applied to a case study, a comparative study on chamber cleaning with NF3 and C2F6. The resuits show that the protposed AHP model is Capable of providing a rational and relevant evaluation.展开更多
According to the regulations of the People's Republic of China national standard as the basis, on the part of chemical industry product quality inspection and analysis of the implementation of computer management has...According to the regulations of the People's Republic of China national standard as the basis, on the part of chemical industry product quality inspection and analysis of the implementation of computer management has developed a set of software applications, the software in chemical products quality inspection and analysis of the means of management is an innovation. The software functions, can automatically process data, judge the product grade, quality analysis, objective and fair, convenient, fast, accurate, stable, practical, and easy to popularize.展开更多
Electrochemical transformation emerges as an important solution to sustainable energy conversion and chemical production.Conventional electrolytic systems usually operate under galvanostatic or potentiostatic conditio...Electrochemical transformation emerges as an important solution to sustainable energy conversion and chemical production.Conventional electrolytic systems usually operate under galvanostatic or potentiostatic conditions that sometimes result in unsatisfactory efficiencies or selectivities.Pulse electrolysis by pulsating and programming the potentials/currents can feature unique tunability to the electrodeelectrolyte interface properties that can give rise to drastically different electrochemical behaviors compared to the steady-state counterparts.Although invented almost 100 years ago,pulse electrolysis has received little attention over the period,but has recently attracted a revived focus toward the energyefficient electrolysis.This review will summarize the history and recent efforts of pulse electrolysis in three categories:water electrolysis,CO_(2)electrolysis and other electrolysis.In each section,the advantage of pulse electrolysis over steady-state electrolysis will be discussed in detail,giving a comprehensive overview of the pulse effect on the electrolytic systems.Finally,we will provide our vision of future directions in pulse electrolysis based on previous works.展开更多
The zebra mussel is an important aquatic pest that causes great damage to freshwater-dependent industries, due to biofouling. The main goal of the project discussed here is to develop improved solutions to control thi...The zebra mussel is an important aquatic pest that causes great damage to freshwater-dependent industries, due to biofouling. The main goal of the project discussed here is to develop improved solutions to control this species. Three approaches have been explored in an attempt to design innovative application strategies for existing biocides: (i) encapsulation of toxins; (ii) combination of toxins; (iii) investigation of the seasonal variation of the species' tolerance to toxins. In this paper, the principles behind these approaches and the major results on each topic are presented. The benefits of adopting a chemical product engineering approach in conducting this project are also discussed.展开更多
In the early days after the founding of New China, there were only some poorly equipped small chemical factories in the cities of Shanghai, Shenyang. Dalian, Nanjing and Tianjin across the country, with a total output...In the early days after the founding of New China, there were only some poorly equipped small chemical factories in the cities of Shanghai, Shenyang. Dalian, Nanjing and Tianjin across the country, with a total output value of RMB 170 million. Now, 45 years later, the chemical industry boasts 23 branches. 40, 000 kinds of products, a total output value of RMB 330 billion and a total import and export volume of RMB 20 billion, according to Gu Xiulian, Minister of Chemical Industry in a speech at the ’94 Beijing International展开更多
1 Introduction Magnesium salts are very important by-product of salt lake industry in West China.Nearly 200 million cubic meters of waste brine are released to the environment
Polyvinylpyrrolidone (PVP) developed by the Henan Kaiyuan Refined Chemical Works is a kind of soluble high molecular refined chemical product, with strong solvency and bond power and it is a principal medicinal supple...Polyvinylpyrrolidone (PVP) developed by the Henan Kaiyuan Refined Chemical Works is a kind of soluble high molecular refined chemical product, with strong solvency and bond power and it is a principal medicinal supplementary ingredient. It can be used as a bonding agent for making medicinal tablets and particles, and as a dissolving agent for injection a gents, a diluent for capsules, a liquor and pigmentated agent,展开更多
Following high speed growth in consecutive years, the development speed of China’s chemical products imports & exports declined by a wide margin in 1996. The annual total import & export value of chemical pro...Following high speed growth in consecutive years, the development speed of China’s chemical products imports & exports declined by a wide margin in 1996. The annual total import & export value of chemical products was US$31.7 billion, a growth of 6.6 percent over 1995. The growth range was down 30 percentage points compared with the rate in the same period of the previous year. Of these, export value was US$12.396 billion, a growth of 4.7 percent; import value was US$19.297 billion, a growth of 8 percent. The growth rate was down 27 and 33 percentage points over the previous year respectively.展开更多
Linalool,a high-reactivity volatile chemical product(VCP)commonly found in cleaning products and disinfectants,is increasingly recognized as an emerging contaminant,especially in indoor air.Understanding the gas-phase...Linalool,a high-reactivity volatile chemical product(VCP)commonly found in cleaning products and disinfectants,is increasingly recognized as an emerging contaminant,especially in indoor air.Understanding the gas-phase oxidation mechanism of linalool is crucial for assessing its impact on atmospheric chemistry and human health.Using quantum chemical calculations and computational toxicology simulations,we investigated the atmospheric transformation and toxicity evolution of linalool under low and high NO/HO_(2)·levels,representing indoor and outdoor environments.Our findings reveal that linalool can undergo the novel mechanisms involving concerted peroxy(RO_(2)·)and alkoxy radical(RO·)modulated autoxidation,particularly emphasizing the importance of cyclization reactions indoors.This expands the widely known RO_(2)·-dominated H-shift-driven autoxidation and proposes a generalized autoxidation mechanism that leads to the formation of low-volatility secondary organic aerosol(SOA)precursors.Toxicological analysis shows that over half of transformation products(TPs)exhibited higher carcinogenicity and respiratory toxicity compared to linalool.We also propose time-dependent toxic effects of TPs to assess their long-term toxicity.Our results indicate that the strong indoor emission coupled with slow consumption rates lead to significant health risks under an indoor environment.The results highlight complex indoor air chemistry and health concerns regarding persistent toxic products during indoor cleaning,which involves the use of linalool or other VCPs.展开更多
In chemical product design,the aim is to formulate a product with desired performance.Ingredients and internal product structure are two key drivers of product performance with direct impact on the mechanical,electric...In chemical product design,the aim is to formulate a product with desired performance.Ingredients and internal product structure are two key drivers of product performance with direct impact on the mechanical,electrical,and thermal properties.Thus,there is a keen interest in elucidating the dependence of product performance on ingredients,structure,and the manufacturing process to form the structure.Design of product structure,particularly microstructure,is an intrinsically complex problem that involves different phases of different physicochemical properties,mass fraction,morphology,size distribution,and interconnectivity.Recently,computational methods have emerged that assist systematic microstructure quantification and prediction.The objective of this paper is to review these computational methods and to show how these methods as well as other developments in product design can work seamlessly in a proposed performance,ingredients,structure,and manufacturing process framework for the design of structured chemical products.It begins with the desired target properties and key ingredients.This is followed by computation for microstructure and then selection of processing steps to realize this microstructure.The framework is illustrated with the design of nanodielectric and die attach adhesive products.展开更多
This study examines the large amount of agricultural waste produced in Egypt between 2010 and 2019 by analysing data from various departments within the Agriculture Ministry.It also provides a comprehensive database o...This study examines the large amount of agricultural waste produced in Egypt between 2010 and 2019 by analysing data from various departments within the Agriculture Ministry.It also provides a comprehensive database on the biomass available from agricultural waste in Egypt and its potential applications for producing power,heat and chemical products.When biomass-pyrolysis systems powered by solar energy are used,research demonstrates the potential to convert agricultural waste into a variety of chemical compounds.This approach utilizes solar energy,a clean and renewable source,and has wide-ranging industrial and power generation applications.Despite Egypt’s reliance on agriculture,the country currently utilizes little biomass for energy production and has not previously used it as a source for creating chemical products,which could potentially save on the imported oil used in these industries.The findings of the study are graphically presented using histograms,pie charts,etc.The overall production of residues reached the 30-Mt level in 2019.Because it contains the most rice-cultivated land,Dakahlia(Lower Egypt region)produces the highest percentage of the total residue(37.17%).Qena governorate(Upper Egypt region)produces 1.14 metric tons of residues,with sugarcane accounting for 20.3%of the total.展开更多
The aim of this work is to boost the combined hydrogen and added-values compounds generation(acetaldehyde, acetic acid and ethyl acetate) through ethanol electrochemical reforming using bimetallic anodes. In particula...The aim of this work is to boost the combined hydrogen and added-values compounds generation(acetaldehyde, acetic acid and ethyl acetate) through ethanol electrochemical reforming using bimetallic anodes. In particular, the influence of the secondary metal on the electrochemical performance as well as on the product distribution was studied. For that purpose, Pt X/C electrocatalysts(where X corresponds to Cu, Co, Ni and Ru) were synthesized by the modified polyol method and tested in both half-cell and proton exchange membrane(PEM) cell configurations. Characterization results showed that incorporation of Ni and Co into the Pt matrix enhances the morphological properties of the material, providing smaller crystallite sizes, higher active surface areas and hence, better dispersion when comparing to Ru and Cu-based electrocatalysts. Ethanol oxidation reaction(EOR) was evaluated by cyclic, linear voltammetry and chronopotentiometry assays. Pt Co/C and Pt Ni/C exhibited the highest electrocatalytic activity at high polarization levels, which translate into an improvement of more than 30%(up to 1050 m A cm^(-2)) in the hydrogen production and chemical yields. On the other hand, Pt Ru/C results more advantageous for a lower potential interval(<0.85 V) promoting the acetic acid production despite sacrificing ethanol conversion. Pt Cu/C presented the lowest results in both electrochemical performance and product distribution. Such differences in the electrochemical performance can be rationalized in terms of the synergistic effect between both metals(particle size distribution, grade of dispersion and hydrophilic behavior), which demonstrate that the incorporation of a different secondary metal plays an essential role in the EOR development.展开更多
GB/T 13245-91 1 Theme and Scope This standard specifies the method abstract, reagents, apparatus, specimen, analyzing procedure, result calculation and permissible tolerance used for determination of the total carbon ...GB/T 13245-91 1 Theme and Scope This standard specifies the method abstract, reagents, apparatus, specimen, analyzing procedure, result calculation and permissible tolerance used for determination of the total carbon with combustion gravimetric method.展开更多
This standard specifies the method summary, reagents, apparatus, sampling, procedure, test results calculation and permissible tolerance of the determination of magnesium oxide by CyDTA volumetric method.
Pigments Everbright Brand pigments, exported in the past four decades, rank first in China for their annual export volume because of wide variety and stable colour. Inorganic pigments: iron oxide red, iron oxide yello...Pigments Everbright Brand pigments, exported in the past four decades, rank first in China for their annual export volume because of wide variety and stable colour. Inorganic pigments: iron oxide red, iron oxide yellow, iron oxide black, ultramaring blue, milori blue, lead oxide red,展开更多
Solar energy utilization has drawn attention due to ever-increasing environmental and energy issues.Photoelectrochemical(PEC)and photocatalytic(PC)water splitting for hydrogen production,which is the most popular and ...Solar energy utilization has drawn attention due to ever-increasing environmental and energy issues.Photoelectrochemical(PEC)and photocatalytic(PC)water splitting for hydrogen production,which is the most popular and well-established solar-to-chemical conversion process,has been studied thoroughly to date but is now facing limitations related to low conversion efficiency.To resolve this issue,research in PEC cells or photocatalysts has recently aimed to produce alternative value-added chemicals by modifying their redox reactions,which potentially enables high economic reward to compensate for the low efficiency.Here,various kinds of redox reactions that decouple classic water splitting reactions to produce value-added chemicals via PEC and PC processes are introduced.Successful coupling of CO_(2) reduction,O_(2) reduction and organic synthesis with either water oxidation or water reduction is comprehensively discussed from the perspective of basic fundamental and product selectivity in terms of the band structure of materials,cocatalyst design,and thermodynamics and kinetics of the reactions.Throughout the review,future challenges and opportunities are suggested with respect to the redesigned artificial synthesis,which might be an alternative development for the commercialization of PEC or PC value-added chemical production technologies in the near future.展开更多
The nanotechnology is of great siguifieance to the country's future economic, social development and national security, and it will bring a revolutionary change to the medicine, manufacturing, materials and informati...The nanotechnology is of great siguifieance to the country's future economic, social development and national security, and it will bring a revolutionary change to the medicine, manufacturing, materials and information communication and other industries, therefore, in recent years, nano science and technology is greatly favored all over the world especially in developed countries. All the countries (areas) in the world have developed the nanotechnology as the main driver of the technical innovation in the twenty-first century, and have formulated development strategies and plans, to promote and guide their development in nanotechnology, which lead to fiercer and fiercer competition. In this paper, the author mainly introduces the application of nano materials in catalysis, filtration, separation, paint and new fine chemical industry and so on.展开更多
A kind of second-order implicit fractional step characteristic finite difference method is presented in this paper for the numerically simulation coupled system of enhanced (chemical) oil production in porous media....A kind of second-order implicit fractional step characteristic finite difference method is presented in this paper for the numerically simulation coupled system of enhanced (chemical) oil production in porous media. Some techniques, such as the calculus of variations, energy analysis method, commutativity of the products of difference operators, decomposition of high-order difference operators and the theory of a priori estimates are introduced and an optimal order error estimates in l^2 norm is derived. This method has been applied successfully to the numerical simulation of enhanced oil production in actual oilfields, and the simulation results ate quite interesting and satisfactory.展开更多
A kind of second-order implicit upwind fractional step finite difference methods are presented for the numerical simulation of coupled systems for enhanced (chemical) oil production with capillary force in the porou...A kind of second-order implicit upwind fractional step finite difference methods are presented for the numerical simulation of coupled systems for enhanced (chemical) oil production with capillary force in the porous media. Some techniques, e.g., the calculus of variations, the energy analysis method, the commutativity of the products of difference operators, the decomposition of high-order difference operators, and the theory of a priori estimate, are introduced. An optimal order error estimate in the l2 norm is derived. The method is successfully used in the numerical simulation of the enhanced oil production in actual oilfields. The simulation results are satisfactory and interesting.展开更多
基金Supported by the National Natural Science Foundation of China (No.20376025, No.20536020) the China Excellent YoungScientist Fund (No.20225620).
文摘With the increasing public consciousness on environmental issues, chemical products and process designs require simultaneous satisfaction and compromise of environmental and economical requirements. To fulfill the two conflicting while complementary objectives, a systematic approach for life cycle design of a chemical product is proposed in this article. Multiattribute decision-making is adopted in a trade-off consideration of both technical economical evaluation and environmental impacts assessment using the analytic hierarchy process (AHP) approach. On the basis of an evaluation of the relative importance of the criteria multicriteria decision making is performed. In this study, an AHP model is used to derive single a criteria score by analyzing the environmental impact and life cycle cost of a product, respectively. And a fluctuant weight analysis is put forth to calculate the integrated index of the product to enable products to be ranked or selected intuitionally and conveniently. The proposed AHP model has been applied to a case study, a comparative study on chamber cleaning with NF3 and C2F6. The resuits show that the protposed AHP model is Capable of providing a rational and relevant evaluation.
文摘According to the regulations of the People's Republic of China national standard as the basis, on the part of chemical industry product quality inspection and analysis of the implementation of computer management has developed a set of software applications, the software in chemical products quality inspection and analysis of the means of management is an innovation. The software functions, can automatically process data, judge the product grade, quality analysis, objective and fair, convenient, fast, accurate, stable, practical, and easy to popularize.
基金supports from the National Key R&D program of China(2019YFC1604602)supports from the National Key Basic Research Program of China(2019YFC1906700)the National Natural Science Foundation of China(21876049,51878643)。
文摘Electrochemical transformation emerges as an important solution to sustainable energy conversion and chemical production.Conventional electrolytic systems usually operate under galvanostatic or potentiostatic conditions that sometimes result in unsatisfactory efficiencies or selectivities.Pulse electrolysis by pulsating and programming the potentials/currents can feature unique tunability to the electrodeelectrolyte interface properties that can give rise to drastically different electrochemical behaviors compared to the steady-state counterparts.Although invented almost 100 years ago,pulse electrolysis has received little attention over the period,but has recently attracted a revived focus toward the energyefficient electrolysis.This review will summarize the history and recent efforts of pulse electrolysis in three categories:water electrolysis,CO_(2)electrolysis and other electrolysis.In each section,the advantage of pulse electrolysis over steady-state electrolysis will be discussed in detail,giving a comprehensive overview of the pulse effect on the electrolytic systems.Finally,we will provide our vision of future directions in pulse electrolysis based on previous works.
基金the Portuguese Foundation for Science and Technology (scholarship SFRH/BD/18731/2004 and Research Project Grant POCI/EQU/59305/2004).
文摘The zebra mussel is an important aquatic pest that causes great damage to freshwater-dependent industries, due to biofouling. The main goal of the project discussed here is to develop improved solutions to control this species. Three approaches have been explored in an attempt to design innovative application strategies for existing biocides: (i) encapsulation of toxins; (ii) combination of toxins; (iii) investigation of the seasonal variation of the species' tolerance to toxins. In this paper, the principles behind these approaches and the major results on each topic are presented. The benefits of adopting a chemical product engineering approach in conducting this project are also discussed.
文摘In the early days after the founding of New China, there were only some poorly equipped small chemical factories in the cities of Shanghai, Shenyang. Dalian, Nanjing and Tianjin across the country, with a total output value of RMB 170 million. Now, 45 years later, the chemical industry boasts 23 branches. 40, 000 kinds of products, a total output value of RMB 330 billion and a total import and export volume of RMB 20 billion, according to Gu Xiulian, Minister of Chemical Industry in a speech at the ’94 Beijing International
基金supported by the National Natural Science Foundationthe National Key Technologies R&D Program (2011BAE28B01)the 863 Program (2013AA032501)
文摘1 Introduction Magnesium salts are very important by-product of salt lake industry in West China.Nearly 200 million cubic meters of waste brine are released to the environment
文摘Polyvinylpyrrolidone (PVP) developed by the Henan Kaiyuan Refined Chemical Works is a kind of soluble high molecular refined chemical product, with strong solvency and bond power and it is a principal medicinal supplementary ingredient. It can be used as a bonding agent for making medicinal tablets and particles, and as a dissolving agent for injection a gents, a diluent for capsules, a liquor and pigmentated agent,
文摘Following high speed growth in consecutive years, the development speed of China’s chemical products imports & exports declined by a wide margin in 1996. The annual total import & export value of chemical products was US$31.7 billion, a growth of 6.6 percent over 1995. The growth range was down 30 percentage points compared with the rate in the same period of the previous year. Of these, export value was US$12.396 billion, a growth of 4.7 percent; import value was US$19.297 billion, a growth of 8 percent. The growth rate was down 27 and 33 percentage points over the previous year respectively.
基金National Natural Science Foundation of China-Creative Research Group Fund(22221004)National Natural Science Foundation of China(22306002)+3 种基金National Key Research and Development Program of China(2022YFC3701000,Task 2)China Postdoctoral Science Foundation(2023M730054)ACCC Flagship funded by the Academy of Finland(337549)European Commission Horizon Europe project FOCI(101056783).
文摘Linalool,a high-reactivity volatile chemical product(VCP)commonly found in cleaning products and disinfectants,is increasingly recognized as an emerging contaminant,especially in indoor air.Understanding the gas-phase oxidation mechanism of linalool is crucial for assessing its impact on atmospheric chemistry and human health.Using quantum chemical calculations and computational toxicology simulations,we investigated the atmospheric transformation and toxicity evolution of linalool under low and high NO/HO_(2)·levels,representing indoor and outdoor environments.Our findings reveal that linalool can undergo the novel mechanisms involving concerted peroxy(RO_(2)·)and alkoxy radical(RO·)modulated autoxidation,particularly emphasizing the importance of cyclization reactions indoors.This expands the widely known RO_(2)·-dominated H-shift-driven autoxidation and proposes a generalized autoxidation mechanism that leads to the formation of low-volatility secondary organic aerosol(SOA)precursors.Toxicological analysis shows that over half of transformation products(TPs)exhibited higher carcinogenicity and respiratory toxicity compared to linalool.We also propose time-dependent toxic effects of TPs to assess their long-term toxicity.Our results indicate that the strong indoor emission coupled with slow consumption rates lead to significant health risks under an indoor environment.The results highlight complex indoor air chemistry and health concerns regarding persistent toxic products during indoor cleaning,which involves the use of linalool or other VCPs.
文摘In chemical product design,the aim is to formulate a product with desired performance.Ingredients and internal product structure are two key drivers of product performance with direct impact on the mechanical,electrical,and thermal properties.Thus,there is a keen interest in elucidating the dependence of product performance on ingredients,structure,and the manufacturing process to form the structure.Design of product structure,particularly microstructure,is an intrinsically complex problem that involves different phases of different physicochemical properties,mass fraction,morphology,size distribution,and interconnectivity.Recently,computational methods have emerged that assist systematic microstructure quantification and prediction.The objective of this paper is to review these computational methods and to show how these methods as well as other developments in product design can work seamlessly in a proposed performance,ingredients,structure,and manufacturing process framework for the design of structured chemical products.It begins with the desired target properties and key ingredients.This is followed by computation for microstructure and then selection of processing steps to realize this microstructure.The framework is illustrated with the design of nanodielectric and die attach adhesive products.
基金This work was supported by the Egyptian Science&Technology development Fund(STDF)of Egypt-China International Joint research(Grant No.41554).
文摘This study examines the large amount of agricultural waste produced in Egypt between 2010 and 2019 by analysing data from various departments within the Agriculture Ministry.It also provides a comprehensive database on the biomass available from agricultural waste in Egypt and its potential applications for producing power,heat and chemical products.When biomass-pyrolysis systems powered by solar energy are used,research demonstrates the potential to convert agricultural waste into a variety of chemical compounds.This approach utilizes solar energy,a clean and renewable source,and has wide-ranging industrial and power generation applications.Despite Egypt’s reliance on agriculture,the country currently utilizes little biomass for energy production and has not previously used it as a source for creating chemical products,which could potentially save on the imported oil used in these industries.The findings of the study are graphically presented using histograms,pie charts,etc.The overall production of residues reached the 30-Mt level in 2019.Because it contains the most rice-cultivated land,Dakahlia(Lower Egypt region)produces the highest percentage of the total residue(37.17%).Qena governorate(Upper Egypt region)produces 1.14 metric tons of residues,with sugarcane accounting for 20.3%of the total.
基金We gratefully acknowledge the Spanish Ministry of Science and Innovation(project PID2019-107499RB-100 and FPI grant BES-2017-081181)for the financial support.
文摘The aim of this work is to boost the combined hydrogen and added-values compounds generation(acetaldehyde, acetic acid and ethyl acetate) through ethanol electrochemical reforming using bimetallic anodes. In particular, the influence of the secondary metal on the electrochemical performance as well as on the product distribution was studied. For that purpose, Pt X/C electrocatalysts(where X corresponds to Cu, Co, Ni and Ru) were synthesized by the modified polyol method and tested in both half-cell and proton exchange membrane(PEM) cell configurations. Characterization results showed that incorporation of Ni and Co into the Pt matrix enhances the morphological properties of the material, providing smaller crystallite sizes, higher active surface areas and hence, better dispersion when comparing to Ru and Cu-based electrocatalysts. Ethanol oxidation reaction(EOR) was evaluated by cyclic, linear voltammetry and chronopotentiometry assays. Pt Co/C and Pt Ni/C exhibited the highest electrocatalytic activity at high polarization levels, which translate into an improvement of more than 30%(up to 1050 m A cm^(-2)) in the hydrogen production and chemical yields. On the other hand, Pt Ru/C results more advantageous for a lower potential interval(<0.85 V) promoting the acetic acid production despite sacrificing ethanol conversion. Pt Cu/C presented the lowest results in both electrochemical performance and product distribution. Such differences in the electrochemical performance can be rationalized in terms of the synergistic effect between both metals(particle size distribution, grade of dispersion and hydrophilic behavior), which demonstrate that the incorporation of a different secondary metal plays an essential role in the EOR development.
文摘GB/T 13245-91 1 Theme and Scope This standard specifies the method abstract, reagents, apparatus, specimen, analyzing procedure, result calculation and permissible tolerance used for determination of the total carbon with combustion gravimetric method.
文摘This standard specifies the method summary, reagents, apparatus, sampling, procedure, test results calculation and permissible tolerance of the determination of magnesium oxide by CyDTA volumetric method.
文摘Pigments Everbright Brand pigments, exported in the past four decades, rank first in China for their annual export volume because of wide variety and stable colour. Inorganic pigments: iron oxide red, iron oxide yellow, iron oxide black, ultramaring blue, milori blue, lead oxide red,
基金Sungsoon Kim,Kwang Hee Kim and Cheoulwoo Oh contributed equally as cofirst authors.Kan Zhang acknowledges the support from NSFC(51802157,21902104)the Natural Science Foundation of Jiangsu Province of China(BZ2020063)Jong Hyeok Park acknowledges the support from the National Research Foundation(NRF)of Korea(2019R1A4A1029237,2021M3E6A1015823,2017M3A7B4041987).
文摘Solar energy utilization has drawn attention due to ever-increasing environmental and energy issues.Photoelectrochemical(PEC)and photocatalytic(PC)water splitting for hydrogen production,which is the most popular and well-established solar-to-chemical conversion process,has been studied thoroughly to date but is now facing limitations related to low conversion efficiency.To resolve this issue,research in PEC cells or photocatalysts has recently aimed to produce alternative value-added chemicals by modifying their redox reactions,which potentially enables high economic reward to compensate for the low efficiency.Here,various kinds of redox reactions that decouple classic water splitting reactions to produce value-added chemicals via PEC and PC processes are introduced.Successful coupling of CO_(2) reduction,O_(2) reduction and organic synthesis with either water oxidation or water reduction is comprehensively discussed from the perspective of basic fundamental and product selectivity in terms of the band structure of materials,cocatalyst design,and thermodynamics and kinetics of the reactions.Throughout the review,future challenges and opportunities are suggested with respect to the redesigned artificial synthesis,which might be an alternative development for the commercialization of PEC or PC value-added chemical production technologies in the near future.
文摘The nanotechnology is of great siguifieance to the country's future economic, social development and national security, and it will bring a revolutionary change to the medicine, manufacturing, materials and information communication and other industries, therefore, in recent years, nano science and technology is greatly favored all over the world especially in developed countries. All the countries (areas) in the world have developed the nanotechnology as the main driver of the technical innovation in the twenty-first century, and have formulated development strategies and plans, to promote and guide their development in nanotechnology, which lead to fiercer and fiercer competition. In this paper, the author mainly introduces the application of nano materials in catalysis, filtration, separation, paint and new fine chemical industry and so on.
基金supported by the Major State Basic Research Development Program of China(G19990328)National Tackling Key Program(2011ZX05011-004+6 种基金2011ZX0505220050200069)National Natural Science Foundation of China(11101244112712311077112410372052)Doctorate Foundation of the Ministry of Education of China(20030422047)
文摘A kind of second-order implicit fractional step characteristic finite difference method is presented in this paper for the numerically simulation coupled system of enhanced (chemical) oil production in porous media. Some techniques, such as the calculus of variations, energy analysis method, commutativity of the products of difference operators, decomposition of high-order difference operators and the theory of a priori estimates are introduced and an optimal order error estimates in l^2 norm is derived. This method has been applied successfully to the numerical simulation of enhanced oil production in actual oilfields, and the simulation results ate quite interesting and satisfactory.
基金Project supported by the Major State Basic Research Development Program of China(No.G19990328)the National Natural Science Foundation of China(Nos.10771124,10372052,and 11101244)+2 种基金the National Tackling Key Problems Program of China(Nos.2011ZX05011-004,2011ZX05052,and 2005020069)the Doctorate Foundation of the Ministry of Education of China(No.20030422047)the Natural Science Foundation of Shandong Province of China(No.ZR2011AM015)
文摘A kind of second-order implicit upwind fractional step finite difference methods are presented for the numerical simulation of coupled systems for enhanced (chemical) oil production with capillary force in the porous media. Some techniques, e.g., the calculus of variations, the energy analysis method, the commutativity of the products of difference operators, the decomposition of high-order difference operators, and the theory of a priori estimate, are introduced. An optimal order error estimate in the l2 norm is derived. The method is successfully used in the numerical simulation of the enhanced oil production in actual oilfields. The simulation results are satisfactory and interesting.