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1.
Angew Chem Int Ed Engl ; 62(26): e202304007, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37072344

RESUMO

How to transfer industrial exhaust gases of nitrogen oxides into high-values product is significantly important and challenging. Herein, we demonstrate an innovative method for artificial synthesis of essential α-amino acids from nitric oxide (NO) by reacting with α-keto acids through electrocatalytic process with atomically dispersed Fe supported on N-doped carbon matrix (AD-Fe/NC) as the catalyst. A yield of valine with 32.1 µmol mgcat -1 is delivered at -0.6 V vs. reversible hydrogen electrode, corresponding a selectivity of 11.3 %. In situ X-ray absorption fine structure and synchrotron radiation infrared spectroscopy analyses show that NO as nitrogen source converted to hydroxylamine that promptly nucleophilic attacked on the electrophilic carbon center of α-keto acid to form oxime and subsequent reductive hydrogenation occurred on the way to amino acid. Over 6 kinds of α-amino acids have been successfully synthesized and gaseous nitrogen source can be also replaced by liquid nitrogen source (NO3 - ). Our findings not only provide a creative method for converting nitrogen oxides into high-valued products, which is of epoch-making significance towards artificial synthesis of amino acids, but also benefit in deploying near-zero-emission technologies for global environmental and economic development.


Assuntos
Aminoácidos Essenciais , Óxido Nítrico , Aminoácidos , Hidrogenação , Carbono , Gases , Cetoácidos
2.
Molecules ; 26(19)2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34641531

RESUMO

The occurrences, distributions, and risks of 55 target volatile organic compounds (VOCs) in water, sediment, sludge, and soil samples taken from a chemical industrial park and the adjacent area were investigated in this study. The Σ55-VOCs concentrations in the water, sediment, sludge, and soil samples were 1.22-5449.21 µg L-1, ND-52.20 ng g-1, 21.53 ng g-1, and ND-11.58 ng g-1, respectively. The main products in this park are medicines, pesticides, and novel materials. As for the species of VOCs, aromatic hydrocarbons were the dominant VOCs in the soil samples, whereas halogenated aliphatic hydrocarbons were the dominant VOCs in the water samples. The VOCs concentrations in water samples collected at different locations varied by 1-3 orders of magnitude, and the average concentration in river water inside the park was obviously higher than that in river water outside the park. However, the risk quotients for most of the VOCs indicated a low risk to the relevant, sensitive aquatic organisms in the river water. The average VOCs concentration in soil from the park was slightly higher than that from the adjacent area. This result showed that the chemical industrial park had a limited impact on the surrounding soil, while the use of pesticides, incomplete combustion of coal and biomass, and automobile exhaust emissions are all potential sources of the VOCs in the environmental soil. The results of this study could be used to evaluate the effects of VOCs emitted from chemical production and transportation in the park on the surrounding environment.

3.
Environ Manage ; 43(6): 1039-47, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19340481

RESUMO

The Conversion of Cropland to Forest and Grassland Program (CCFG), which was initiated by the Chinese government in 1999, is a cropland retirement program with integrated objectives for ecological preservation and local development. The purpose of this article was to study the influencing factors of attitude and economic strategies in rural households toward the CCFG. Rural households' knowledge, attitude and economic strategies toward the CCFG were investigated through a questionnaire survey in Qira, China. Influencing factors of attitude and strategies of households were analyzed using a logit model technique. The analysis indicated that household's income level, environmental knowledge of the program, and program implementation were significant influencing factors in a household's attitude toward the CCFG, while major influencing factors of household strategies were their regional background and availability of income generation sources. Meaningful association was not found between attitude and strategy choices. Rich households had more strategy choices, while poor households were usually confined to low input strategies with uncertain income. To sustain their livelihood, the poor need extra assistances in marketing, loan granting, employment training, information, and technical services.


Assuntos
Agricultura/economia , Atitude , Conservação dos Recursos Naturais/métodos , População Rural , Adulto , Agricultura/classificação , China , Demografia , Humanos , Pessoa de Meia-Idade , Poaceae , Avaliação de Programas e Projetos de Saúde , Opinião Pública , População Rural/classificação , Fatores Socioeconômicos , Inquéritos e Questionários , Árvores , Adulto Jovem
4.
Huan Jing Ke Xue ; 28(3): 673-8, 2007 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-17633654

RESUMO

Analytic hierarchy process and a specialist investigation were applied to value the three PCBs treatment technologies qualitatively and quantitatively, in which the environmental, technological, social and economic factors were considered. The most important factor is thought to be environmental impact. Incineration is proved to be the most suitable technology in this period according to the research. For the high concentration of PCBs pollutants, or the low concentration of PCBs pollutants with good economic performance and large quantity of waste, incineration is considered the best. For the low concentration of PCBs pollutants in the area with bad economic performance and with little quantity of waste, cement kiln and landfill are thought to be suitable. It is also suggested that pollutants be treated at the nearest place. What's more, the measures to improve the three technologies are discussed and the policy comments on PCBs treatment are presented.


Assuntos
Poluentes Ambientais/análise , Recuperação e Remediação Ambiental/métodos , Bifenilos Policlorados/análise , Monitoramento Ambiental , Resíduos Industriais
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