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1.
Huan Jing Ke Xue ; 41(10): 4455-4461, 2020 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124377

RESUMO

As flue gas desulfurization (FGD) was one of the most important purification processes of coal-fired boilers, we selected four boilers, which were equipped with wet limestone, furnace calcium injection, ammonia-based, and double-alkali FGDs, to research the influence of FGDs on the flue particulate matter (PM). The flue PM before and after the FGD were sampled using laboratory resuspension and dilution tunnel sampling methods, respectively, and the PM was analyzed for its chemical composition (i.e., ions, elements, and carbon). The results showed that the types of desulfurizers could influence the composition of the flue PM. After passing through the wet limestone, ammonia-based, and double-alkali FGDs, the proportion of Ca, NH4+, and Na in PM2.5 increased from 5.1% to 24.8%, from 0.8% to 7.3%, and from 0.9% to 1.7%, respectively. The influence of wet and dry FGDs on the flue PM were different. The fraction of ions in the PM emitted from the wet FGD were higher than those from the dry FGD. The proportion of SO42- in the flue PM2.5 increased from 2.0% and 6.7% to 9.6% and 11.9% using the wet limestone and ammonia-based FGDs, respectively, and Cl- increased from 0.4% and 1.2% to 3.8% and 5.2%. In addition, the amount of heavy metals (e.g., Cr, Pb, Cu, Ti, and Mn) in PM2.5 declined after the wet FGDs. The PM2.5 emitted from the dry FGD boiler was richer in crustal elements, such as Al, Si, and Fe, than that from the wet FGDs. The wet FGDs also effected the carbonaceous components of the flue PM. After passing through the wet limestone and ammonia-based FGDs, the proportion of elemental carbon in the flue PM2.5 decreased from 6.1% to 0.9% and from 3.6% to 0.7% respectively, but the organic carbon content did not decrease.

2.
Huan Jing Ke Xue ; 40(9): 3949-3961, 2019 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854857

RESUMO

The characteristics of volatile organic compound (VOCs) species from various production procedures of wood-based panel production and other industrial processes in Chengdu were analyzed through gas chromatography-mass spectrometry (GC-MS) and other methods specified in national standards after the emissions of typical enterprises of wood-based panel production, pharmaceutical manufacturing, chemical production and other industrial processes in Chengdu had been sampled using sampling bottles and SUMMA canisters. Generally, the process of wood-based panel production includes glue making, glue mixing, sorting, and hot pressing, whereas the process of pharmaceutical manufacturing includes workshop production and wastewater treatment. The results showed that the main contribution species of VOCs in wood-based panel production and pharmaceutical manufacturing is oxygenated VOCs (OVOCs), accounting for more than 50% of the total VOCs emitted. The species from organized and unorganized emissions of formaldehyde manufacturing differed significantly. The main species of organized emissions was OVOCs, and that of unorganized emissions was halohydrocarbons. Emissions of VOCs from coating manufacturing were strongly correlated with the raw materials, and the corresponding emission species were composed mainly of aromatics and OVOCs. Except for glue mixing, the main species of VOCs in other process procedures of wood-based panel production was formaldehyde, with emission proportion of more than 50%. The primary species of VOCs in various processes of pharmaceutical manufacturing was ethanol; however 1,4-dioxane, ethyl acetate, and toluene were also important species. Moreover, the main VOCs from formaldehyde manufacturing were composed mainly of acetone and ethanol, and those of coating manufacturing were aromatic hydrocarbons such as p-xylene. The ozone formation potential was to characterize the reactivity of pollution sources in VOCs from wood-based panel production, pharmaceutical manufacturing, and chemical production. The results showed that the species of VOCs in different industries contributed similarly to the reactivity and that these species were mainly high-activity species such as formaldehyde, ethanol, and other OVOCs as well as some aromatic hydrocarbons. Therefore, supervision and regulation of enterprises of industrial processes is required with a focus on species with relatively large ozone formation potential. In addition, it is necessary to analyze the emission characteristics and chemical mechanism of various industries and to control O3 generation from the sources.

3.
Huan Jing Ke Xue ; 40(4): 1613-1626, 2019 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087901

RESUMO

Based on the measured data in the literature, VOCs (volatile organic compounds) source profiles were revised and reconstructed without OVOCs (oxygenated volatile organic compounds) species to obtain the normalized VOCs source profiles. Using the 2015 Sichuan emission inventory, source profiles based on the 1 km×1 km gridded speciated VOCs emission inventory were developed, and the ozone formation potentials of the species were estimated to assess the environmental impact on ozone formation. The established VOCs source profile database consists of 45 source profiles and 519 species. Since the source profiles were established based on the revision and reconstruction of pollution sources, such as biomass burning and transportation, that are rich in OVOCs, the source profile database is better applicable to establishing the speciated VOCs emission inventory and source apportionment. The speciated VOCs emission inventory showed that the total anthropogenic emission of VOCs in Sichuan Province was 773.8 kt, of which the emissions of alkanes, olefins, alkynes, aromatics, OVOCs, halohydrocarbons, and other VOCs accounted for 21.6%, 10.0%, 1.7%, 28.0%, 26.2%, 4.2%, and 8.3% of the total respectively. The total OFP (Ozone formation potential) was 2584.9 kt, of which the OFPs of the VOCs groups mentioned above accounted for 6.9%, 26.1%, 0.5%, 42.3%, 23.2%, 0.4%, and 0.5% respectively. The main VOCs species emitted in all cities of Sichuan Province were aromatics, OVOCs, and alkanes; however, there were some significant regional differences:transportation in Chengdu, Ya'an, Aba, Ganzi, and Liangshan made a greater contribution to VOCs emissions, with alkane emissions accounting for a higher proportion in the total VOCs emission. As a heavy industrial city, Panzhihua suffered most from emissions from industrial processes, which contain a relatively high proportion of alkanes. Solvent use in Deyang, Meishan, Suining, and Ziyang made a great contribution to the VOCs emissions, and the OVOCs emission was relatively high. Emissions of VOCs and species with relatively high OFPs in Sichuan Province were mainly distributed in the Sichuan Basin, which has a dense population and highly developed industry, as well as some areas in Liangshan and Panzhihua. The main source of m-xylene and toluene was solvent use; therefore, m-xylene and toluene were relatively concentrated in developed urban areas. In addition, biomass burning contributed greatly to the emissions of ethene and formaldehyde; therefore, ethene and formaldehyde were mainly distributed in the cultivated areas of agriculturally advanced Eastern Sichuan and Southern Sichuan.

4.
Front Physiol ; 9: 1697, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30555341

RESUMO

Aphidius gifuensis Ashmead (Hymenoptera: Aphidiidae) is a solitary endoparasitoid used in the biological control of various aphids. Diapause plays an important role in the successful production and deployment of A. gifuensis. Diapause can effectively extend the shelf life of biological control agents and solve several practical production problems like long production cycles, short retention periods, and discontinuities between supply and demand. In recent years, studies have been conducted on the environmental regulation and physiological and biochemical mechanisms of diapause in A. gifuensis. Nevertheless, the molecular mechanism of diapause in this species remains unclear. In this study, we compared the transcriptomes and proteomes of diapause and non-diapause A. gifuensis to identify the genes and proteins associated with this process. A total of 557 transcripts and 568 proteins were differentially expressed between the two groups. Among them, (1) genes involved in trehalose synthesis such as glycogen synthase, glycogen phosphorylase, and trehalose 6-phosphate synthase were upregulated in diapause at mRNA or protein level while glycolysis and gluconeogenesis-related genes were downregulated, suggesting that A. gifuensis stores trehalose as an energy resource and cryoprotectant; (2) the expression of immune-related genes like C-type lectins, hemocyanin, and phenoloxidase was increased, which helps to maintain immunity during diapause; (3) a chitin synthase and several cuticular protein genes were upregulated to harden the cuticle of diapausing A. gifuensis larval. These findings improve our understanding of A. gifuensis. diapause and provide the foundation for further pertinent studies.

5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 607-11, 2017 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30292180

RESUMO

In order to research the effect of X-ray fluorescence (XRF) analysis on the results in the sample's micro particles, MCNPX models had been established for an X-ray fluorescence analyzer in this paper. It had studied the characteristics of the samples with different particle sizes, the fluorescence peak counts, the peak to total ratios and the peak to source ratios. A micro particle analysis experiment had been designed for its verification. The results showed that: as for the relationship between the fluorescence intensity and the particle sizes, the MCNPX calculations were consistent with the theoretical, but contrary with the experimental results; the reason is that some hypotheses about samples in the MCNPX models were contrary with the actual states; the samples were crushed by grinding to small particles and tableting process, the MCNPX calculations and experimental results can be conversion; when the particle sizes of the samples reached the certain sizes, the fluorescence peak counts, the peak to total ratios and the peak to source ratios were stable value; within a particular size range, the influence of the particle size effects cannot be ignored, otherwise this influence can be ignored. The research methods and conclusions in this paper can provide a technical reference guide for X-ray analysis in practices.

6.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 16(3): 525-30, 2008 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-18549622

RESUMO

This study was aimed to explore the expression level of the unknown cgi-100 gene in human leukemia K562 cells treated with matrine, and to investigate effect of cgi-100 on proliferation of K562 cells. The expression level of cgi-100 was detected by RT-PCR in K562 cells before and after being treated with matrine; pIRES2-EGFP/cgi-100 eukaryotic expression vector was constructed by DNA recombinant technique and was introduced into K562 cells by liposome-mediated DNA transfection. The cgi-100 gene expression level, growth-curve, and cell cycle of the modified K562-cgi-100 cells were detected by RT-PCR, Trypan blue staining and FCM. Morphological changes were observed under the optical and electron microscopes. The results indicated that the expression level of cgi-100 decreased in K562 cells treated with matrine. Heterochromatin decreased, euchromatin and the proportion of S phase in K562-cgi-100 cells increased, and cell proliferation enhanced. It is concluded that the expression of cgi-100 mRNA decreased in a dose- and time-dependent manner in the K562 cells treated with matrine and over-expression of cgi-100 elevates the proliferation and the immaturity level of K562-cgi-100 cells.


Assuntos
Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Genes Neoplásicos/genética , Quinolizinas/farmacologia , Regulação Neoplásica da Expressão Gênica , Genes Neoplásicos/fisiologia , Humanos , Células K562 , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Matrinas
7.
Zhonghua Xue Ye Xue Za Zhi ; 28(12): 823-7, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18476594

RESUMO

OBJECTIVES: To investigate the expression status of IER3IP1 gene during matrine induced K562 cell differentiation, and to figure out the function of IER3IP1 gene in K562 cell line. METHODS: Trypan-blue staining was used to analyze the growth inhibitory effect of matrine on K562 cells. Semi-quantitative RT-PCR was employed to investigate the expression status of IER3IP1 gene treated with different time and dosage of matrine. The alteration of cellular morphology, cellular proliferation and ultra-microstructure were observed and the cell cycle was detected on the recombinant IER3IP1 gene eukaryotic expression vector eYFP-IER3IP1 plasmid transfected K562 cells (K562/eYFP-IER3IPl). RESULTS: Matrine inhibited the growth of K562 cells and reduced the expression of IER3IP1 gene. The expression level of IER3IP1 gene was transiently increased to three-to-four times in a dose-dependent manner after treated with matrine for 2 - 3 hours. Then, in 6-48 hours it maintained at a low level as compared with the control group. The proliferation rate of the K562/eYFP-IER3IP1 cells significantly slowed down with more cells blocked in G0-G1 phase (P < 0.05). The number of erythroid blast cells began to increase after 24 hours of matrine treatment. At the same time, differentiated erythroid cells could be observed. CONCLUSIONS: Matrine can inhibit the growth of K562 cells, and transiently increase the expression level of IER3IP1 gene in a dose-dependent manner. The sensitivity of K562 cells to matrine maybe increased after being transfected by the eYFP-IER3IP1 plasmid, indicating a possible involvement of the IER3IP1 gene in the early response of the cells to matrine and its possible role in the erythroid cell differentiation.


Assuntos
Alcaloides/farmacologia , Proteínas de Transporte/metabolismo , Proteínas de Membrana/metabolismo , Quinolizinas/farmacologia , Proteínas de Transporte/genética , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Células K562 , Proteínas de Membrana/genética , Matrinas
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