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Detailed analysis of PCBs and PCDD/Fs impurities in a dielectric oil sample (ASKAREL Nr 1740) from an imported transformer in China

Jun HUANG, Yamei HUI, Toru MATSUMURA, Gang YU, Shubo DENG, Makoto YAMAUCHI, Changmin WU, Norimasa YAMAZAKI

《环境科学与工程前沿(英文)》 2014年 第8卷 第2期   页码 195-204 doi: 10.1007/s11783-013-0527-y

摘要: Homolog and congener profiles of polychlorinated biphenyls (PCBs), polychlorinated dibenzo- - dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in commercial PCBs formulations are useful information for the source appointment of PCBs contamination as well as the risk assessment caused by potential exposure. Dielectric oil (ASKAREL Nr 1740) in an imported transformer found in China was sampled and analyzed by isotope dilution technology using high resolution gas chromatography-high resolution mass spectrometry (HRGC/HRMS). The detailed homolog and congener profiles of PCBs obtained were compared with those of known Aroclor formulations. High similarity in the homolog profile between the oil sample and Aroclor 1260 was found, with the hexachlorinated and heptachlorinated biphenyls accounting for more than 80.2% of the total PCBs concentration. Severn indicator PCBs contribute about 30%, while 12 PCB congeners (i.e., #153, #143, #168, #180, #149, #165, #138, #170, #190, #187, #174, #181) account for more than 50% of the total PCB concentrations. Total concentration of PCDDs, PCDFs and dioxin-like PCBs (DL-PCBs) was found to be 740 ng TEQ/g, of which 620 ng TEQ/g came from DL-PCBs. The contribution of PCDDs to the total TEQ was neglectable. The concentration of PCDFs homologs follows the order of OCDF>HxCDFs>HpCDFs>PeCDFs>TeCDFs, which is in consistence with the previous study on Aroclor 1260. Three DL-PCBs congeners (i.e., #118, #156, #157) accounted for 77% of the total concentration of DL-PCBs, also they contribute 72% in the TEQ caused by DL-PCBs.

关键词: profiles of polychlorinated biphenyls (PCBs)     polychlorinated dibenzo-p-dioxins (PCDDs)     polychlorinated dibenzofurans (PCDFs)     Askarel transformer     insulating fluid    

PCDD/Fs emission, risk characterization, and reduction in China’s secondary copper production industry

Haiqian LI, Yonglong LU, Li LI

《环境科学与工程前沿(英文)》 2013年 第7卷 第4期   页码 589-597 doi: 10.1007/s11783-013-0495-2

摘要: Secondary copper production is one of the key polychlorinated dibenzo- -dioxins and dibenzofurans (PCDD/Fs) emission sources in China, but research and data on this issue are rare. In 2004, when the Stockholm Convention entered into force in China, PCDD/Fs emissions from secondary copper production contributed to 32.2% of the total release. In this paper, PCDD/Fs emission dynamics from secondary copper industry were discussed and cumulative risks were characterized. From 2004 to 2009, industrial policies played an indirect role in PCDD/Fs reduction, but its effects are still limited. The Yangtze River Delta, Pearl River Delta and central regions were among the top three of dioxin emissions from secondary copper production in China. Shanghai, Shandong, Zhejiang, and Jiangxi had comparatively higher accumulated risk and were recommended as the priority regions for promoting PCDD/Fs emission control in China. From 2009 to 2015, the PCDD/Fs emission dynamics in the secondary copper industry were presented through simulation. PCDD/Fs emission equations were established, resulting in the recommendation of control technology conversion rate at 30% for small scale smelters and 51%–57% for large and medium-sized enterprises in 2015. In conclusion, both indirect policy and direct control technology retrofitting should be integrated for more effective PCDD/Fs emission reduction in secondary copper industry.

关键词: polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs)     secondary copper production     emission     risk     China    

Hydrothermal treatment of MSWI fly ash for simultaneous dioxins decomposition and heavy metal stabilization

Jinlong XIE, Yuyan HU, Dezhen CHEN, Bin ZHOU,

《环境科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 108-115 doi: 10.1007/s11783-010-0013-8

摘要: Researches on the hydrothermal treatment of municipal solid waste incineration (MSWI) fly ash were conducted to eliminate dioxins and stabilize heavy metals. In order to enhance decomposing polychlorinated dibenzo-dioxins (PCDDs) and polychlorinated dibenzo-furans (PCDFs) during hydrothermal process, a strong reductant carbohydrazide (CHZ) is introduced. A hydrothermal reactor was set up by mixing raw MSWI fly ash or the pre-treated fly ash with water and then heated to a pre-set temperature; CHZ was spiked into solution according to specially defined dosage. Experimental results showed that under the temperatures of 518K and 533K, the decomposition rates of PCDDs/PCDFs were over 80% and 90%, respectively, by total concentration. However, their toxic equivalent (TEQ) decreased only slightly or even increased due to the rising in concentration of congeners 2, 3, 7, 8-TCDD/TCDF, which might be resulted from the highly chlorinated congeners losing their chlorine atoms and being degraded during the hydrothermal process. Better results of TEQ reduction were also obtained under the higher tested temperature of 533K and reactor with addition of 0.1%wt CHZ was corresponded to the best results. Good stabilization of heavy metals was also obtained in the same hydrothermal process especially when ferrous sulphate was added as auxiliary agent.

关键词: municipal solid wastes incineration (MSWI)     fly ashes     polychlorinated dibenzo-dioxins (PCDDs)     polychlorinated dibenzo-furans (PCDFs)     hydrothermal     heavy metal stabilization    

Experimental study on low temperature thermal treatment of polychlorinated dibenzo-p-dioxins and dibenzofurans

YAN Jianhua, CHEN Tong, LU Shengyong, LI Xiaodong, GU Yueling, CEN Kefa

《能源前沿(英文)》 2007年 第1卷 第3期   页码 280-284 doi: 10.1007/s11708-007-0039-1

摘要: The effects of temperature and time on polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) distribution in fly ash of a municipal solid waste incinerator (MSWI) were studied in a tubular oven under nitrogen atmosphere. The PCDD/Fs in the gas phase and solid phase were detected by high-resolution gas chromatography coupled with low resolution mass spectrometry (HRGC/LRMS) se para tely. The experimental results showed that the major congener was octa-chlorinated dibenzo--dioxin (OCDD) in the gas phase and the low chlorinated congeners were the major products in the solid phase. There were high levels of OCDD in the gas phase in several experimental conditions although the PCDD/Fs in the solid phase could be decomposed. The optimum condition for PCDD/Fs decomposition in fly ash was a heating time of 60 min at 400 vH under nitrogen atmosphere.

关键词: congener     polychlorinated     temperature     chromatography     high-resolution    

Legacies and health risks of heavy metals, polybrominated diphenyl ethers, and polychlorinated dibenzo-dioxins

《环境科学与工程前沿(英文)》 2023年 第17卷 第7期 doi: 10.1007/s11783-023-1679-z

摘要:

● Heavy metals and organic toxins may persist in legacy sites for a long time.

关键词: E-waste     Human health risk     Organ risk     Heavy metal toxicity     PBDE     PCDD/F    

Assessment of toxicity of two nitroaromatic compounds in the freshwater fish

Hongyan SHEN, Jixi GAO, Jinsheng WANG

《环境科学与工程前沿(英文)》 2012年 第6卷 第4期   页码 518-523 doi: 10.1007/s11783-012-0427-6

摘要: This study was conducted to evaluate the toxicological response of -nitrotoluene and -nitroaniline to the key fish species, . A freshwater fish bioassay based on the 96 h was used to estimate the single and joint toxicity of the two chemicals. The toxicity of -nitrotoluene was greater than that of -nitroaniline based on 96 h values of 40.74 mg·L and 48.99 mg·L , respectively. Both compounds had moderate toxicity toward , and this toxicity increased with the exposure duration and concentration. Binary mixtures of the compounds were more toxic than the individual compounds at 96 h, and they acted upon partial addition. When the exposure time was longer, the toxicity increased for mixtures of compounds with the same concentration or toxicity. The results of this study suggest that exposure to a combination of these chemicals would result in a higher environmental risk in aquatic systems than exposure to either compound alone. Further research is needed to investigate the combined effects and sublethal toxicity of -nitrotoluene and -nitroaniline, since they are both still used in China.

关键词: joint toxicity     Cyprinus carpio     LC50     p-nitrotoluene     p-nitroaniline     toxic unit    

Synthesis of depsipeptides from

Hongfei CAO, Yakai FENG, Heyun WANG, Li ZHANG, Musammir KHAN, Jintang GUO

《化学科学与工程前沿(英文)》 2011年 第5卷 第4期   页码 409-415 doi: 10.1007/s11705-011-1141-9

摘要: By using the corresponding -amino acid sodium as initiator, -caprolactone-depsipeptides CL-Ala and CL-Leu were prepared by the reactions of -caprolactone (CL) with -alanine and -leucine, respectively, and -dioxanone-depsipeptide (PDO-Leu) was prepared by the reaction of -dioxanone (PDO) with -leucine. Two poly( -caprolactone) oligomers (PCL-Ala and PCL-Leu) of different molecular weights with depsipeptide unit were synthesized by controlling the feed ratio of -amino acid sodium and CL. The presence of the depsipeptide structure in these obtained products was confirmed by H NMR spectra and the molecular weight of the poly( -caprolactone) oligomers was measured by gel permeation chromatography (GPC). These products contain a hydroxyl group and a carboxyl group in one molecule, which means they could act as bifunctional monomers for further polymerization to prepare high molecular weight polymers. By this way, the depsipeptide unit could be introduced into the polymers and the biodegradation rates of the novel polymers could be well controlled in vivo by the tailored molecular structures.

关键词: ?-caprolactone     p-dioxanone     L-alanine     L-leucine     depsipeptide    

The <italic>rpoSitalic> deficiency suppresses acetate accumulation in glucose-enriched culture of <italic>Escherichia coliitalic> under an aerobic condition

Prayoga SURYADARMA, Yoshihiro OJIMA, Yuto FUKUDA, Naohiro AKAMATSU, Masahito TAYA

《化学科学与工程前沿(英文)》 2012年 第6卷 第2期   页码 152-157 doi: 10.1007/s11705-012-1287-0

摘要: The role of on the central carbon metabolism was investigated through analyzing the deficiency of this regulon gene under aerobic and glucose-enriched culture conditions. The experimental results showed that while the wild type cells exhibited an overflow metabolism effect, the -deleting mutation alleviated this effect with the significant suppression of acetate accumulation under a high glucose condition. This gene deletion also induced the twofold upregulation of and one-tenth downregulation of , respectively. The overflow metabolism effect was confirmed to be recovered by re-introducing gene into the mutant. These results demonstrated changed the central carbon metabolism toward acetate overflow through dehydrogenation of pyruvate and reduction of TCA cycle activity.

关键词: Escherichia coli     rpoS     aerobic and glucose-enriched culture     overflow metabolism    

Optimization of cellulase production using

Saravanan P, Muthuvelayudham R, Rajesh Kannan R, Viruthagiri T

《化学科学与工程前沿(英文)》 2012年 第6卷 第4期   页码 443-452 doi: 10.1007/s11705-012-1225-1

摘要: The potential of for cellulase production using pineapple waste as substrate has been investigated. A maximum cellulase activity of 9.23 U/mL is obtained under the optimum experimental conditions: pH (5.5), temperature (37.5°C), initial substrate concentration (3%), inoculum concentration (6.6 × 10 ?CFU/mL), and culture time (6 days). Box-Behnken design (BBD) statistical tool and genetic algorithm (GA) are used to optimize the process parameters. The BBD study of linear and quadratic interactive effects of experimental variables on the desired response of cellulase activity showed that the second order polynomial is significant ( = 0.9414). The experimental cellulase activity under the optimal conditions identified by the BBD is 9.23 U/mL and that by GA is 6.98 U/mL. This result indicates that the BBD model gives better result than GA in the present case.

关键词: cellulase     pineapple waste     Trichoderma reesei     Box-Behnken design     genetic algorithm    

Purification of artemisinin from quercetin by anti-solvent crystallization

MALWADE, Haiyan QU, Ben-Guang RONG, Lars P. CHRISTENSEN

《化学科学与工程前沿(英文)》 2013年 第7卷 第1期   页码 72-78 doi: 10.1007/s11705-013-1305-x

摘要: In the present work, anti-solvent crystallization of artemisinin from four different organic solvents (methanol, ethanol, acetonitrile, and acetone) was studied. Water was used as anti-solvent. The effect of an impurity (quercetin) on the performance of anti-solvent crystallization of artemisinin was investigated. The fundamental process data such as solubility of artemisinin in pure organic solvents and their binary mixtures with varying composition water were measured at room temperature. The solubility of quercetin was measured only in pure organic solvents at room temperature. Anti-solvent crystallization experiments were designed based on the fundamental process data determined. Firstly, the anti-solvent crystallization of artemisinin without impurity was performed from all four organic solvents and then the experiments were repeated with addition of an impurity (quercetin) while keeping all other process parameters constant. Two different concentrations of impurity, i.e., 10% and 50% of its solubility, in the respective organic solvents at room temperature were used. The effect of impurity on performance of anti-solvent crystallization was evaluated by comparing the yield and purity of the artemisinin obtained with those in the absence of impurity. Results of the present work demonstrated that the presence of quercetin in the solution does not affect the final yield of artemisinin from the solution of each of four organic solvents used. However, the purity of artemisinin crystals were reduced when quercetin concentration was 50% of its solubility in all solvents studied.

关键词: anti-solvent crystallization     artemisinin     quercetin     solubility     Artemisia annua    

Biosorption and biotransformation of crystal violet by

Tao PAN, Suizhou REN, Jun GUO, Meiying XU, Guoping SUN

《环境科学与工程前沿(英文)》 2013年 第7卷 第2期   页码 185-190 doi: 10.1007/s11783-012-0435-6

摘要: DN322p, an offspring of DN322, has the capacity to adsorb and decolorize triphenylmethane dyes in wastewater simultaneously. As a common triphenylmethane dye, crystal violet (CV) was chosen to test the decolorization characteristics of DN322p. Within 0.5 h, the strain DN322p adsorbed a large amount of CV, producing a deep-colored cell pellet and colorless supernatant. The colors of the cell pellet and supernatant lightened over time. The supernatant and dichloromethane extract of the cell pellet both showed conspicuous CV and leuco CV (LCV) characteristic absorbance peaks at 590 nm and 260 nm, respectively, in the UV-vis spectral analysis. This finding indicated that the DN322p cells can adsorb the two dyes. A 99% (w/w) decolorization rate was achieved within 2.5 h with shaking at 30°C for 50 mg CV·L . High Performance Liquid Chromatography (HPLC) analysis of the dichloromethane extract of the supernatant and cell pellet confirmed that CV was mainly converted into its leuco form. Dead cells had a similar adsorption capacity with living cells. About 90% of CV in the dye solution (50 mg·L ) was removed by autoclaved cells with an optical delnsity at 600 nm (OD ) above 1.0.

关键词: crystal violet     decolorization     biosorption     biotransformation     Aeromonas hydrophila DN322p    

Investigations on color variations of <italic>Morpho rhetenoritalic> butterfly wing scales

Guanglan LIAO, Haibo ZUO, Xuan JIANG, Xuefeng YANG, Tielin SHI

《机械工程前沿(英文)》 2012年 第7卷 第4期   页码 394-400 doi: 10.1007/s11465-012-0347-y

摘要:

Experiments and simulations are carried out to investigate the optical properties of butterfly wing scales. The upper surface of a male butterfly wing presents a single-layer of scales, the microstructures of which are responsible for the brilliant blue color. The color varies from cyan blue to yellow green and soon afterwards returns back to cyan blue when some ethanol is dropped on the upper surface. At the start of the ethanol volatilization process, the reflection spectrum remains stable. As the ethanol further volatilizes, the peak reflectance decreases slightly, then increases dramatically. Meanwhile, the peak wavelength keeps approximately constant, then decreases, and keeps almost stable at the end of the process. Therefore, the optical properties depend strongly on the varying ambient conditions, including the refractive index and the thickness of the packing medium. Moreover, the possible causes for the scales in dark green region after several dropping ethanol experiments are clarified. This research benefits our understanding of the color variation mechanisms of the wing scales, and provides inspiration for further studies and applications.

关键词: Morpho rhetenor     microstructures     color variations     ambient medium    

Administration with

Qi RUI, Qin LU, Dayong WANG

《医学前沿(英文)》 2009年 第3卷 第1期   页码 76-90 doi: 10.1007/s11684-009-0002-0

摘要: During normal metabolism, oxidative byproducts will inevitably generate and damage molecules thereby impairing their biological functions, including the aging process. (补肾抗衰方, ) is a traditional Chinese medicine widely used for clinically treating premature ovarian failure. In the present study, administration at high concentrations significantly increased lifespan, slowed aging-related decline, and delayed accumulation of aging-related cellular damage in wild-type . administration could further largely alleviate the aging defects induced by UV and oxidative stresses, and administration at different concentrations could largely rescue the aging defects in mutant animals. The protective effects of administration on aging process were at least partially dependent on the Ins/IGF-like signaling pathway. Moreover, administration at different concentrations obviously altered the expression patterns of antioxidant genes and suppressed the severe stress responses induced by UV and oxidative stresses, suggesting that -induced tolerance to UV or oxidative stress might result from reactive oxygen species scavenging. administration during development was not necessarily a requirement for UV and oxidative stress resistance, and the concentrations of administrated examined were not toxic for nematodes. Therefore, administration could effectively retrieve the aging defects induced by UV irradiation and oxidative stress in .

关键词: Bushenkangshuai Tang     UV irradiation     oxidative stress     tissue senescence     lifespan     Caenorhabditis elegans    

Mutagenesis and selective breeding of a high producing

Tian WANG, Shiru JIA, Zhilei TAN, Yujie DAI, Shuai SONG, Guoliang WANG

《化学科学与工程前沿(英文)》 2012年 第6卷 第2期   页码 179-183 doi: 10.1007/s11705-012-1273-6

摘要: -Poly- -lysine ( -PL) is an -lysine linear homopolymer, which is produced by bacteria belonging to the family and by ergot fungi. However, the production of -PL by the wild bacteria strain is very low, which limits its utilization. In most bacteria including the genus, -lysine is a precursor of -PL and is biosynthesized by the -aspartate pathway. Aspartokinase (Ask) is the first key enzyme in this pathway and is subject to complex regulation such as the feedback inhibition by the end product amino acids. In addition, phosphoenolpyruvate carboxykinase is feedback-regulated by -aspartate. To reduce these feedback inhibitions and to improve -PL productivity, resistant mutants were produced using sulfaguanidine (SG) + glycine+ -lysine+ -3-hydroxynorvaline (AHV) as selective markers. Using the interaction between -PL and the charged dye in the solid culture medium, hundreds of colonies were simultaneously screened in a quick and effective manner. Finally, one -PL-producing strain, L9, was selected. The productivity of this strain during flask fermentation was 0.77 g/L, which was 15% higher than that of the original strain. Moreover, its fermentation performance and genetic characteristics were very stable.

关键词: ?-poly-L-lysine     plasma     AHV     Streptomyces diastatochromogenes     fermentation    

Biosorption of Cd

Fengyu ZAN, Shouliang HUO, Beidou XI, Xiulan ZHAO

《环境科学与工程前沿(英文)》 2012年 第6卷 第1期   页码 51-58 doi: 10.1007/s11783-011-0206-9

摘要: The biosorption of Cd and Cu onto the immobilized ( ) was investigated in this study. Adsorption kinetics, isotherms and the effect of pH were studied. The results indicated that the biosorption of Cd and Cu on the immobilized was fast at initial stage and then became slow. The maximum biosorption of heavy metal ions on immobilized were observed at pH 4 for Cd and Cu . by the pseudo-second-order model described the sorption kinetic data well according to the high correlation coefficient ( ) obtained. The biosorption isotherm was fitted well by the Langmuir model, indicating possible mono-layer biosorption of Cd and Cu on the immobilized . Moreover, the immobilized after the sorption of Cd and Cu could be regenerated and reused.

关键词: Saccharomyces cerevisiae (S. cerevisiae)     biosorption     heavy metals     immobilization     desorption    

标题 作者 时间 类型 操作

Detailed analysis of PCBs and PCDD/Fs impurities in a dielectric oil sample (ASKAREL Nr 1740) from an imported transformer in China

Jun HUANG, Yamei HUI, Toru MATSUMURA, Gang YU, Shubo DENG, Makoto YAMAUCHI, Changmin WU, Norimasa YAMAZAKI

期刊论文

PCDD/Fs emission, risk characterization, and reduction in China’s secondary copper production industry

Haiqian LI, Yonglong LU, Li LI

期刊论文

Hydrothermal treatment of MSWI fly ash for simultaneous dioxins decomposition and heavy metal stabilization

Jinlong XIE, Yuyan HU, Dezhen CHEN, Bin ZHOU,

期刊论文

Experimental study on low temperature thermal treatment of polychlorinated dibenzo-p-dioxins and dibenzofurans

YAN Jianhua, CHEN Tong, LU Shengyong, LI Xiaodong, GU Yueling, CEN Kefa

期刊论文

Legacies and health risks of heavy metals, polybrominated diphenyl ethers, and polychlorinated dibenzo-dioxins

期刊论文

Assessment of toxicity of two nitroaromatic compounds in the freshwater fish

Hongyan SHEN, Jixi GAO, Jinsheng WANG

期刊论文

Synthesis of depsipeptides from

Hongfei CAO, Yakai FENG, Heyun WANG, Li ZHANG, Musammir KHAN, Jintang GUO

期刊论文

The <italic>rpoSitalic> deficiency suppresses acetate accumulation in glucose-enriched culture of <italic>Escherichia coliitalic> under an aerobic condition

Prayoga SURYADARMA, Yoshihiro OJIMA, Yuto FUKUDA, Naohiro AKAMATSU, Masahito TAYA

期刊论文

Optimization of cellulase production using

Saravanan P, Muthuvelayudham R, Rajesh Kannan R, Viruthagiri T

期刊论文

Purification of artemisinin from quercetin by anti-solvent crystallization

MALWADE, Haiyan QU, Ben-Guang RONG, Lars P. CHRISTENSEN

期刊论文

Biosorption and biotransformation of crystal violet by

Tao PAN, Suizhou REN, Jun GUO, Meiying XU, Guoping SUN

期刊论文

Investigations on color variations of <italic>Morpho rhetenoritalic> butterfly wing scales

Guanglan LIAO, Haibo ZUO, Xuan JIANG, Xuefeng YANG, Tielin SHI

期刊论文

Administration with

Qi RUI, Qin LU, Dayong WANG

期刊论文

Mutagenesis and selective breeding of a high producing

Tian WANG, Shiru JIA, Zhilei TAN, Yujie DAI, Shuai SONG, Guoliang WANG

期刊论文

Biosorption of Cd

Fengyu ZAN, Shouliang HUO, Beidou XI, Xiulan ZHAO

期刊论文