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1.
Huan Jing Ke Xue ; 44(7): 3771-3778, 2023 Jul 08.
Artigo em Zh | MEDLINE | ID: mdl-37438276

RESUMO

Vehicle exhaust is an important anthropogenic source of atmospheric carbonaceous aerosols; of which, the emission factors and stable carbon isotope composition are important basic data. In-use motor vehicles of different types were selected to conduct dynamometer tests using different test cycles and under cold/hot start conditions. The exhaust of each test stage was collected to analyze the carbonaceous components and stable carbon isotopes and to discuss the influencing factors. The total carbon emission factors follow the order:heavy-duty diesel vehicles>light-duty diesel vehicles>light-duty gasoline vehicles. Although the emission factors of light-duty natural gas vehicles were very low at the low- and medium-speed stages, they were similar to those of heavy-duty diesel vehicles at the high-speed stage. The emission factors of cold start were higher than those of hot start, and the emission factors of the NEDC test cycle were lower than those of WLTC (which should be related to the driving speed). The emission factors of organic carbon (OC) of gasoline and natural gas vehicles were much higher than those of elemental carbon (EC) in every test stage. The emission factors of OC and EC of diesel vehicles were similar. The OC/EC of all types of vehicles increased with the increase in driving speed. Stable carbon isotopes in EC were higher than those in OC. The stable carbon isotope in different vehicles follow the order:light-duty gasoline vehicles

2.
Bioprocess Biosyst Eng ; 35(5): 751-60, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22116528

RESUMO

The lignin-modifying enzymes (LMEs) play an important role in decomposition of agricultural residues, which contain a certain amount of lignin. In this study, the production of LMEs by three co-cultivated combinations of Phlebia radiata, Dichomitus squalens and Ceriporiopsis subvermispora and the respective monocultures was comparatively investigated. Laccase and manganese peroxidases (MnP) were significantly promoted in the co-culture of P. radiata and D. squalens, and corncob was verified to be beneficial for laccase and MnP production. Moreover, laccase production by co-culture of P. radiata and D. squalens with high ratio of glucose to nitrogen was higher than low ratio under carbon- and nitrogen-meager conditions. New laccase isoenzymes measured by Native-PAGE were stimulated by co-cultured P. radiata with D. squalens or C. subvermispora, respectively, growing in the defined medium containing corncob, but the expression of laccase was greatly restrained by the co-culturing of D. squalens with C. subvermispora. This study showed that the synergistic and depressing effects of co-cultivation of P. radiata, D. squalens and C. subvermispora on LMEs were species specific.


Assuntos
Coriolaceae/enzimologia , Coriolaceae/crescimento & desenvolvimento , Proteínas Fúngicas/biossíntese , Lacase/biossíntese , Peroxidases/biossíntese , Técnicas de Cocultura , Lignina/metabolismo
3.
Bioprocess Biosyst Eng ; 34(1): 103-11, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20658164

RESUMO

This work aimed to develop the submerged cultivation conditions for improved exopolysaccharides (EPS) production by Armillaria luteo-virens Sacc. The effects of culture temperature, aeration rate, inoculum level, initial pH, and additives on EPS formation and mycelial growth are investigated. The aeration rate, initial pH, and inoculum level significantly affected EPS production under the submerged cultivation. The developed conditions were as follows: cultivation temperature 23 °C, initial pH 5.0, aeration rate 0.5 vvm, 0.5% Tween 80, inoculum level 5% (v/v), and shaking speed 120 r/min. Under the developed conditions, the highest EPS production was 13.01 g/L at 5 days culture time. EPS production was examined in a 5 L bioreactor, and an unstructured kinetic model for EPS formation was well developed. The verified investigations in the large-scale cultivation system showed that the developed models are able to predict the submerged cultivation process of EPS formation. Current results revealed that the submerged cultivation conditions can be utilized to control EPS production, and the unstructured models developed are suitable for explaining EPS production by A. luteo-virens Sacc QH in a large-scale cultivation bioreactor.


Assuntos
Armillaria/metabolismo , Microbiologia Industrial/métodos , Polissacarídeos/biossíntese , Algoritmos , Armillaria/crescimento & desenvolvimento , Reatores Biológicos , Meios de Cultura , Cinética , Modelos Teóricos , Polissacarídeos/isolamento & purificação
4.
J Zhejiang Univ Sci B ; 9(7): 527-35, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18600782

RESUMO

The bglS gene encoding endo-l,3-1,4-beta-glucanase from Bacillus subtilis was cloned and sequenced in this study. The bglS expression cassette, including PGK1 promoter, bglS gene fused to the signal sequence of the yeast mating pheromone alpha-factor (MFalpha1(S)), and ADH1 terminator with G418-resistance as the selected marker, was constructed. Then one of the PEP4 allele of Saccharomyces cerevisiae WZ65 strain was replaced by bglS expression cassette using chromosomal integration of polymerase chain reaction (PCR)-mediated homologous recombination, and the bglS gene was expressed simultaneously. The recombinant strain S. cerevisiae (SC-betaG) was preliminarily screened by the clearing hydrolysis zone formed after the barley beta-glucan was hydrolyzed in the plate and no proteinase A (PrA) activity was measured in fermenting liquor. The results of PCR analysis of genome DNA showed that one of the PEP4 allele had been replaced and bglS gene had been inserted into the locus of PEP4 gene in recombinant strains. Different endo-l,3-1,4-beta-glucanase assay methods showed that the recombinant strain SC-betaG had high endo-l,3-1,4-beta-glucanase expression level with the maximum of 69.3 U/(h.ml) after 60 h of incubation. Meanwhile, the Congo Red method was suitable for the determination of endo-l,3-1,4-beta-glucanase activity during the actual brewing process. The current research implies that the constructed yeast strain could be utilized to improve the industrial brewing property of beer.


Assuntos
Ácido Aspártico Endopeptidases/genética , Glicosídeo Hidrolases/genética , Mutagênese Insercional , Recombinação Genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Sequência de Aminoácidos , Sequência de Bases , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
5.
Environ Pollut ; 236: 49-59, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29414374

RESUMO

China established Domestic Emission Control Area (DECA) for sulphur since 2015 to constrain the increasing shipping emissions. However, future DECA policy-makings are not supported due to a lack of quantitive evaluations. To investigate the effects of current and possible Chinese DECAs policies, a model is presented for the forecast of shipping emissions and evaluation of potential costs and benefits of an DECA policy package set in 2020. It includes a port-level and regional-level projection accounting for shipping trade volume growth, share of ship types, and fuel consumption. The results show that without control measures, both SO2 and particulate matter (PM) emissions are expected to increase by 15.3-61.2% in Jing-Jin-Ji, the Yangtze River Delta, and the Pearl River Delta from 2013 to 2020. However, most emissions can be reduced annually by the establishment of a DECA that depends on the size of the control area and the fuel sulphur content limit. Costs range from 0.667 to 1.561 billion dollars (control regional shipping emissions) based on current fuel price. A social cost method shows the regional control scenarios benefit-cost ratios vary from 4.3 to 5.1 with large uncertainty. Chemical transportation model combined with health model method is used to get the monetary health benefits and then compared with the results from social cost method. This study suggests that Chinese DECAs will reduce the projected emissions at a favorable benefit-cost ratio, and furthermore proposes policy combinations that provide high cost-effective benefits as a reference for future policy-making.


Assuntos
Poluição do Ar/economia , Navios/economia , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/economia , Poluição do Ar/análise , China , Análise Custo-Benefício , Monitoramento Ambiental/economia , Material Particulado/análise , Material Particulado/economia , Navios/estatística & dados numéricos , Enxofre/análise
6.
Food Chem ; 132(1): 619-23, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26434340

RESUMO

Xanthohumol (XN) and related prenylflavonoids are the main bioactive components of hops (Humulus lupulus L.). The current work is to investigate the use of high-speed counter-current chromatography (HSCCC) in search for high isolation of xanthohumol from hops. A solvent system consisted of n-hexane-ethyl acetate-methanol-water at a volume ratio of 5:5:4:3 was employed. The results demonstrated that the constructed method could be well applied for the isolation of xanthohumol from hops extract. After HSCCC isolation procedure, the purity of xanthohumol was over 95% assayed by HPLC and the yield of extraction was 93.60%. The chemical structure identification of xanthohumol was carried out by UV, (1)H NMR and (13)C NMR. The present results demonstrated that xanthohumol could be efficiently obtained using a single HSCCC step from H. lupulus L. extract.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Distribuição Contracorrente/métodos , Flavonoides/química , Humulus/química , Propiofenonas/química , Estrutura Molecular
7.
J Agric Food Chem ; 59(13): 7419-26, 2011 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-21634799

RESUMO

8-Prenylnaringenin (8PN), which presents in hop, enjoys fame as the most potential phytoestrogen. Although a number of health effects are attributed to 8PN, few reports are available about the production of it. In this work, screening of fungi to efficiently transform isoxanthohumol (IXN) into 8PN was designed. The biotransformation of IXN was significantly observed in Eupenicillium javanicum, Cunninghamella blakesleana, and Ceriporiopsis subvermispora under five kinds of transformation conditions. As a comparative result of IXN transformation, E. javanicum was the optimal biocatalyst to produce 8PN. Transformation caused by growing precultured fungal mycelia, a process designated as G2, was a favorable condition for IXN transformation in view of the yield of 8PN. The possible transformation pathway of 8PN bioproduction is postulated in this work. The construction of fungus and transformation mode derived from the current work is viable and an alternative procedure for 8PN formation.


Assuntos
Flavanonas/biossíntese , Fungos/metabolismo , Fitoestrógenos/metabolismo , Xantonas/metabolismo , Biotransformação , Coriolaceae/metabolismo , Cunninghamella/metabolismo , Eupenicillium/metabolismo , Mortierella/metabolismo
8.
Ultrason Sonochem ; 16(5): 599-604, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19110462

RESUMO

Betulin is an abundant naturally occurring triterpene, which makes it a potentially important raw material for a precursor of biologically active compounds. The objective of the current study was to determine the optimum UAE conditions for betulin from B. papyfera bark. The optimum conditions were evaluated with fractional factorial design and optimized using response surface methodology. High yields of betulin were observed from white birch bark by UAE technology. The solvent concentration and the ratio of material to solvent were the most significant parameters on betulin extraction as evaluated through FFD. The extraction conditions were further investigated with central composite design. The fitted second-order model revealed that the optimal conditions consisted of 98% ethonal concentration, 1:42 the ratio of white birch bark to solvent, extraction temperature 50 degrees C, ultrasonic frequency 5kHz and extraction time 3h. Under the optimized condition, the maximum productivity of betulin predicted is 23.17%. The extraction productivity and purity of betulin under the optimized extraction conditions were great higher than that of the non-optimized condition. The present study demonstrates that ultrasound is a great efficiency tool for the fast extraction of betulin from white birch bark.


Assuntos
Betula/química , Extratos Vegetais/química , Triterpenos/química , Triterpenos/isolamento & purificação , Ultrassom , Cromatografia Líquida de Alta Pressão , Cor , Estrutura Molecular , Casca de Planta , Propriedades de Superfície
9.
J Zhejiang Univ Sci B ; 10(10): 769-76, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19817002

RESUMO

Proteinase A (PrA), encoded by PEP4 gene, is a key enzyme in the vacuoles of Saccharomyces cerevisiae. We characterized the effects of PrA on cell growth and glucose metabolism in the industrial S. cerevisiae WZ65. It was observed that the lag phase of cell growth of partial PEP4 gene deletion mutant (36 h) and PrA-negative mutant (48 h) was significantly extended, compared with the wild type strain (24 h) (P<0.05), but PrA had no effect on glucose metabolism either under shaking or steady state cultivations. The logistic model was chosen to evaluate the effect of PrA on S. cerevisiae cell growth, and PrA was found to promote cell growth against insufficient oxygen condition in steady state cultivation, but had no effect in shaking cultivation. The effects of glucose starvation on cell growth of partial PEP4 gene deletion strain and PrA-negative mutant were also evaluated. The results show that PrA partial deficiency increased the adaption of S. cerevisiae to unfavorable nutrient environment, but had no effect on glucose metabolism under the stress of low glucose. During heat shock test, at 60 degrees C the reduced cell viability rate (RCVR) was 10% for the wild type S. cerevisiae and 90% for both mutant strains (P<0.01), suggesting that PrA was a negative factor for S. cerevisiae cells to survive under heat shock. As temperatures rose from 60 degrees C to 70 degrees C, the wild type S. cerevisiae had significantly lower relative glucose consumption rate (RGCR) (61.0% and 80.0%) than the partial mutant (78.0% and 98.5%) and the complete mutant (80.0% and 98.0%) (P<0.05), suggesting that, in coping with heat shock, cells of the PrA mutants increased their glucose consumption to survive. The present study may provide meaningful information for brewing industry; however, the role of PrA in industrial S. cerevisiae physiology is complex and needs to be further investigated.


Assuntos
Ácido Aspártico Endopeptidases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimologia , Ácido Aspártico Endopeptidases/genética , Sequência de Bases , DNA Fúngico/genética , Deleção de Genes , Genes Fúngicos , Glucose/metabolismo , Resposta ao Choque Térmico , Microbiologia Industrial , Cinética , Modelos Biológicos , Mutação , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
10.
Artigo em Zh | MEDLINE | ID: mdl-19035254

RESUMO

OBJECTIVE: To investigate and analyze the wounded's state of ear, nose, throat, neck and head injury in Wenchuan earthquake. METHODS: The 206 wounded cases, who was treated in No. 452 Hospital of People's Liberation Army, were investigated specially with emphasis on injury cause, severity and treatment. RESULTS: The injured 165 cases among the 206 were in hospital, while the cases who related to the injury of ear, nose and throat were 37 cases (22.4%). Among the inpatients, the trauma of otorhinolaryngology and head and neck included: ear injuries totally 13 cases (including hemotympanum 2 cases), extraneous matter 4 cases, haemorrhagic 4 cases, nasalis and the fracture of nasal bone and nasal sinuses 7 cases (including cerebrospinal rhinorrhea 1 case), zygomatic abscess 1 case, fracture of mandible 4 cases, lip injuries 2 cases and hoarse 2 cases. The inpatients were wounded mostly because of falling and stepping. All the inpatients recovered well after properly management by ENT doctors. CONCLUSIONS: Maxillofacial injury of the wounded those were medical evacuation in the earthquake area, was ignored more readily comparing to the injury of other spots, so specialist should examine early and treat properly the people as soon as possible.


Assuntos
Traumatismos Craniocerebrais/terapia , Desastres , Terremotos , Lesões do Pescoço/terapia , Adolescente , China , Orelha Externa/lesões , Orelha Média/lesões , Feminino , Fraturas Ósseas/terapia , Humanos , Masculino , Traumatismos Maxilofaciais/terapia , Adulto Jovem
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