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Keywords

Immunoglobulin G 5

biosorption 5

N₂O 4

n-heptane 4

CH₄ 3

2 2

N 2

N-nitrosodimethylamine 2

N-nitrosodimethylamine (NDMA) 2

Denitrification 2

Glycosylation 2

Greenhouse gas 2

H7N9 2

N 2

N235 2

Salinity 2

competitive adsorption 2

concrete 2

decolorization 2

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Detecting

Chengkun WANG, Xiaojian ZHANG, Jun WANG, Chao CHEN

Frontiers of Environmental Science & Engineering 2012, Volume 6, Issue 6, Pages 770-777 doi: 10.1007/s11783-012-0412-0

Abstract: nitrosodimethylamine (NDMA) and several other nitrosamines have been detected as disinfection by-productsspectrometry method with solid phase extraction sample preparation was developed to study the occurrence of nitrosaminesNDMA and several other nitrosamines were found at fairly high concentrations in several water treatmentA wide range of nitrosamines concentrations and species were observed in different locations.Higher concentrations of nitrosamines were detected in distribution systems that were further away from

Keywords： <italic>N-italic>nitrosamines water treatment plant distribution system ultra-performance liquid chromatography-tandem

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Application of statistical design for the production of inulinase by

RAJASIMMAN, N. RAJAMOHAN

Frontiers of Chemical Science and Engineering 2011, Volume 5, Issue 4, Pages 463-470 doi: 10.1007/s11705-011-1112-1

Abstract: A Plackett-Burman design was employed for screening 18 nutrient components for the production of inulinase using sp. and pressmud as the substrate via solid-state fermentation (SSF). From the experiments, three nutrients viz. yeast extract, FeSO ·7H O, and NH NO were found to be the most significant components. Hence these three components were selected and optimized using Response Surface Methodology (RSM). The optimum conditions are: yeast extract 0.00274 g/gds, FeSO ·7H O 0.00011 g/gds and NH NO 0.00772 g/gds. The effect of the substrate concentration and initial moisture content were also studied. A substrate concentration of 12 g and an initial moisture content of 65% are optimum for the maximum production of inulinase (89 U/gds).

Keywords： inulinase pressmud Response Surface Methodology (RSM) <italic>streptomycesitalic> sp

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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

Frontiers of Chemical Science and Engineering 2012, Volume 6, Issue 2, Pages 152-157 doi: 10.1007/s11705-012-1287-0

Abstract: 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.

Keywords： <italic>Escherichia coliitalic> <italic>rpoSitalic> aerobic and glucose-enriched culture overflow

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Synthesis of depsipeptides from

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

Frontiers of Chemical Science and Engineering 2011, Volume 5, Issue 4, Pages 409-415 doi: 10.1007/s11705-011-1141-9

Abstract: 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.

Keywords： <italic>?italic>-caprolactone <italic>pitalic>-dioxanone <italic>Litalic>-alanine <italic>Litalic>-leucine

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Factors influencing the photodegradation of

Bingbing XU, Zhonglin CHEN, Fei QI, Jimin SHEN, Fengchang WU

Frontiers of Environmental Science & Engineering 2009, Volume 3, Issue 1, Pages 91-97 doi: 10.1007/S11783-009-0013-8

Abstract: In order to provide basic data for practical application,photodegradation experiment of -nitrosodimethylamine (NDMA) in aqueous solution was carried out with a low-pressure Hg lamp. Effects of the initial concentration of NDMA, solution pH, dissolved oxygen, and the presence of humic acid on NDMA photodegradation were investigated. NDMA at various initial concentrations selected in this study was almost completely photodegraded by UV irradiation within 20 min, except that at 1.07 mmol/L, NDMA could be photodegraded almost completely in the acidic and neutral solutions, while the removal efficiency decreased remarkably in the alkaline solution. Dissolved oxygen enhanced the NDMA photodegradation, and the presence of humic acid inhibited the degradation of NDMA. Depending on the initial concentration of NDMA, NDMA photodegradation by UV obeyed the pseudo-first-order kinetics. Dimethylamine, nitrite, and nitrate were detected as the photodegradation products of NDMA. O was found to be the reactive oxygen species present in the NDMA photodegradation process by UV, based on the inhibiting experiments using tert-butanol and sodium azide.

Keywords： <italic>Nitalic>-nitrosodimethylamine (NDMA) ultraviolet irradiation degradation kinetic dimethylamine

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Assessment of toxicity of two nitroaromatic compounds in the freshwater fish

Hongyan SHEN, Jixi GAO, Jinsheng WANG

Frontiers of Environmental Science & Engineering 2012, Volume 6, Issue 4, Pages 518-523 doi: 10.1007/s11783-012-0427-6

Abstract: 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.

Keywords： joint toxicity <italic>Cyprinus carpioitalic> <italic>LCitalic>₅₀ <italic>pitalic>-nitrotoluene <italic>pitalic>-nitroaniline toxic unit

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

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

Frontiers of Mechanical Engineering 2012, Volume 7, Issue 4, Pages 394-400 doi: 10.1007/s11465-012-0347-y

Abstract:

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.

Keywords： <italic>Morpho rhetenoritalic> microstructures color variations ambient medium

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Administration with

Qi RUI, Qin LU, Dayong WANG

Frontiers of Medicine 2009, Volume 3, Issue 1, Pages 76-90 doi: 10.1007/s11684-009-0002-0

Abstract: 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 .

Keywords： <italic>Bushenkangshuai Tangitalic> UV irradiation oxidative stress tissue senescence lifespan <italic>Caenorhabditis elegansitalic>

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Mutagenesis and selective breeding of a high producing

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

Frontiers of Chemical Science and Engineering 2012, Volume 6, Issue 2, Pages 179-183 doi: 10.1007/s11705-012-1273-6

Abstract: -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.

Keywords： <italic>?italic>-poly-<italic>Litalic>-lysine plasma AHV <italic>Streptomyces diastatochromogenesitalic>

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Biosorption of Cd

Fengyu ZAN, Shouliang HUO, Beidou XI, Xiulan ZHAO

Frontiers of Environmental Science & Engineering 2012, Volume 6, Issue 1, Pages 51-58 doi: 10.1007/s11783-011-0206-9

Abstract: 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.

Keywords： <italic>Saccharomyces cerevisiaeitalic> (<italic>S. cerevisiaeitalic>) biosorption heavy metals immobilization

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Factors controlling

Chengkun WANG, Xiaojian ZHANG, Chao CHEN, Jun WANG

Frontiers of Environmental Science & Engineering 2013, Volume 7, Issue 2, Pages 151-157 doi: 10.1007/s11783-013-0482-7

Abstract: The formation of cancinogenic nitrosamines, esp.

Keywords： <italic>Nitalic>-nitrosodimethylamine (NDMA) disinfection by-product dissolved organic nitrogen (DOC

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Nano-hydroxyapatite formation via co-precipitation with chitosan-g-poly(

Yang YU, Hong ZHANG, Hong SUN, Dandan XING, Fanglian YAO

Frontiers of Chemical Science and Engineering 2013, Volume 7, Issue 4, Pages 388-400 doi: 10.1007/s11705-013-1355-0

Abstract: With the excellent biocompatibility and osteoconductivity, nano-hydroxyapatite (nHA) has shown significant prospect in the biomedical applications. Controlling the size, crystallinity and surface properties of nHA crystals is a critical challenge in the design of HA based biomaterials. With the graft copolymer of chitosan and poly( -isopropylacrylamide) in coil and globule states as a template respectively, a novel composite from chitosan-g-poly( -isopropylacrylamide) and nano-hydroxyapatite (CS-g-PNIPAM/nHA) was prepared via co-precipitation. Zeta potential analysis, thermogravimetric analysis and X-ray diffraction were used to identify the formation mechanism of the CS-g-PNIPAM/nHA composite and its morphology was observed by transmission electron microscopy. The results suggested that the physical aggregation states of the template polymer could induce or control the size, crystallinity and morphology of HA crystals in the CS-g-PNIPAM/nHA composite. The CS-g-PNIPAM/nHA composite was then introduced to chitosan-gelatin (CS-Gel) polyelectronic complex and the cytocompatibility of the resulting CS-Gel/composite hybrid film was evaluated. This hybrid film was proved to be favorable for the proliferation of MC 3T3-E1 cells. Therefore, the CS-g-PNIPAM/nHA composite is a potential biomaterial in bone tissue engineering.

Keywords： chitosan poly(<italic>Nitalic>-isopropylacrylamide) hydroxyapatite coil globule bone tissue engineering

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What can be taught in architectural design? —

Xing RUAN

Frontiers of Structural and Civil Engineering 2010, Volume 4, Issue 4, Pages 450-455 doi: 10.1007/s11709-010-0098-y

Abstract: This essay begins with a reflection on what has been taught in architectural design since the turn of the twentieth century. I shall trace back to the two disciplinary foundations of the French école des Beaux-Arts – and – in the education of an architect in the eighteenth and nineteenth centuries. I shall then attempt to superimpose and on a modern disciplinary framework, say that of mathematics, which leads to musings on a series of architectural problems that include pattern versus type, stability versus mobility, orthogonal versus oblique, confinement versus transparency, and aging versus metallic sheen. These paradoxes, I suggest, demand the education of an architect to address both the instrumental pattern of a building configuration and the ambient felt qualities of a room, rather than vision alone.

Keywords： architectural design teaching <italic>partiitalic> and <italic>pochéitalic>

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Highly effective extraction of oil from soybean by pretreatment of solid-state fermentation with fungi

Xiaojuan NIU, Shuyi QIU, Yuangen WU, Jie YUAN, Yingying XU

Frontiers of Chemical Science and Engineering 2011, Volume 5, Issue 1, Pages 122-125 doi: 10.1007/s11705-010-0533-6

Abstract: The solid-state prefermentation by (CICC 2377) and (CICC 40536) was employed to increase the oil extraction yield from soybean. The influence of incubation time on oil yield was investigated. The maximum oil yield extracted from the substrate prefermented by for 96 h was 23%, which increased by 47.4% compared with control (15.6%). In the same fermentation conditions, the maximum oil yield extracted from substrate prefermented by was 21.6%, which increased by 38.5% compared with control (15.6%). The quality of soybean oil was not changed obviously by the pretreatment of fermentation with fungi.

Keywords： soybean <italic>Aspergillus nigeritalic> <italic>Aspergillus flavusitalic> solid-state fermentation

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Spatial and seasonal variations in bacterial communities of the Yellow Sea by T-RFLP analysis

Hongyuan WANG, Xiaolu JIANG, Ya HE, Huashi GUAN

Frontiers of Environmental Science & Engineering 2009, Volume 3, Issue 2, Pages 194-199 doi: 10.1007/s11783-009-0018-3

Abstract: Four typical coastal sites (rocky shore, sandy shore, mud flat shore, and artificial harbor) at the Yellow Sea were chosen to investigate the spatial and seasonal variations in bacterial communities. This was accomplished by using terminal restriction fragment length polymorphism (T-RFLP) analysis of PCR amplified 16S rDNA fragments. Two kinds of tetrameric restriction enzymes, I and I, were used in the experiment to depict the bacterial community diversity in different marine environments. It was found that the community compositions digested by the two enzymes separately were different. However, the results of bacterial community diversity derived from them were similar. The MDA analysis results of T-RFLP profiles coming from I and I both exhibited a significant seasonal community shift for bacteria and a relatively low spatial variation among the four locations. With I as the sample, the pair wise -tests also revealed that variations were minor between each pair of marine environments, with ranging from 0.198 to 0.349. However, the bacterial community structure in the mud flat site depicted a larger difference than each of the other three sites ( ranging from 0.282 to 0.349).

Keywords： restriction fragment length polymorphism (T-RFLP) bacterial community structure marine microbial diversity <italic>Hhaitalic>I <italic>Mspitalic>I

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Title Author Date Type Operation

Detecting

Chengkun WANG, Xiaojian ZHANG, Jun WANG, Chao CHEN

Journal Article

Application of statistical design for the production of inulinase by

RAJASIMMAN, N. RAJAMOHAN

Journal Article

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

Journal Article

Synthesis of depsipeptides from

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

Journal Article

Factors influencing the photodegradation of

Bingbing XU, Zhonglin CHEN, Fei QI, Jimin SHEN, Fengchang WU

Journal Article

Assessment of toxicity of two nitroaromatic compounds in the freshwater fish

Hongyan SHEN, Jixi GAO, Jinsheng WANG

Journal Article

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