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医院中子照射器I型堆 5

GM(1 4

1)模型 2

MCNP 2

中子通量密度 2

代谢 2

医院中子照射器 2

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(GaxIn1−x)2O3薄膜；带隙可调谐；磁控溅射 1

1 1

1) 1

1)幂模型 1

1860 MPa等级 1

1T/2H-MoS₂ 1

2R-1C模型；嵌入式系统；参数估计；非迭代方法；二次型 1

4250 m 1

5-戊二胺 1

5G；交叉振子；双极化天线；终端天线；超宽带 1

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Kinetic roughening transition and missing regime transition of melt crystallized polybutene-1 tetragonal

Motoi YAMASHITA

《化学科学与工程前沿（英文）》 2009年第3卷第2期页码 125-134 doi: 10.1007/s11705-009-0001-3

摘要： The morphology and lateral growth rate of polybutene-1 ( -PB1) have been investigated for crystallization from the melt over a wide range of crystallization temperatures from 50 to 110°C. The morphology of -PB1 crystals is a rounded shape at crystallization temperatures lower than 85°C, while lamellar single crystals possess faceted morphology at higher crystallization temperatures. The kinetic roughening transition occurs around 85°C. The nucleation and growth mechanism for crystallization does not work below 85°C, since the growth face is rough. However, the growth rate shows the supercooling dependence derived from the nucleation and growth mechanism. The nucleation theory seems still to work even for rough surface growth. Possible mechanisms for the crystal growth of this polymer are discussed.

关键词： isotactic polybutene-1 tetragonal phase (form Ⅱ) melt crystallization growth rate kinetic roughening morphology

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Lamellar thickness transition of melt-crystallized polybuten-1 tetragonal phase: configurational change

Motoi YAMASHITA

《化学科学与工程前沿（英文）》 2009年第3卷第1期页码 26-32 doi: 10.1007/s11705-009-0002-2

摘要： Lamellar crystal thickness of isotactic polybutene-1 ( -PB1) have been investigated for crystallization in the melt over a wide range of crystallization temperature from 40°C to 90°C by small angle X-ray scattering experiments and density measurements. The crystal thickness demonstrates two linear dependences on inverse supercooling and a transition from one dependence to the other has been observed around = 65°C. Each of the two dependences obeys the nucleation theory in the high and low supercooling ranges, respectively. Chain folding free energy determined from the low supercooling range is larger than that determined from the high supercooling range. Possible mechanisms for the transition are discussed taking account of entropy of chain folding directions.

关键词： isotactic polybutene-1 tetragonal phase crystal thickness melt growth chain folding small angle X-ray scattering nucleation theory end surface free energy

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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

《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

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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

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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

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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

《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

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Synthesis of

Lili ZHANG, Ming LIU, Shijun MA, Yaodong HUANG, Yongmei WANG

《化学科学与工程前沿（英文）》 2013年第7卷第4期页码 408-414 doi: 10.1007/s11705-013-1343-4

摘要： Two new -symmetric primary-secondary diamines were synthesized via the reaction of ( , )-1,2-diphenyl ethylene diamine with 3,5-ditert-butyl salicylaldehyde and salicylaldehyde, respectively, followed by reduction with NaBH . The combination of the ligand from 3,5-ditert-butyl salicylaldehyde with CuBr could effciently catalyze the Henry reaction to afford -nitroalkanols in moderate to good yields (up to 87%) and high enantioselectivities (up to 88% ). A possible mechanism of the reaction was proposed.

关键词： enantioselective Henry reaction C₁-symmetric diamines asymmetric reaction nitroalkanol

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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

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Are the SNPs of NKX2-1 associated with papillary thyroid carcinoma in the Han population of Northern

null

《医学前沿（英文）》 2014年第8卷第1期页码 113-117 doi: 10.1007/s11684-014-0310-x

摘要：

Papillary thyroid carcinoma (PTC) is one of the most common tumors of the thyroid gland. The common risk factors of PTC include ionizing radiation, positive family history, and thyroid nodular disease. PTC was identified in Europeans by conducting a genome-wide association study, and a strong association signal with PTC was observed in rs944289 and NKX2-1 (located at the 14q13.3 locus), which was probably the genetic risk factor of PTC. This study aimed to examine the association of this gene with PTC in Chinese. A total of 354 patients with PTC and 360 healthy control subjects from the Han population of Northern China were recruited in the study. These individuals were genotyped to determine rs12589672, rs12894724, rs2076751, and rs944289. The association of rs944289 with PTC was obtained (C vs. T, P=0.027, OR=1.264, 95% CI=1.026-1.557; and C/C-C/T vs. T/T, P=0.034, OR=1.474, 95% CI=1.028-2.112). Conducting a subgroup analysis, we found a marginal difference in the allele frequency distribution of rs944289 (adjusted P=0.062) between the patients with PTC and multi-nodular goiter and the control subjects. We also observed an interaction (P=0.029; OR=2.578, 95% CI=1.104-6.023) between rs944289 and diabetes in patients with PTC. In conclusion, rs944289 was associated with an increased risk of PTC in the Han population of Northern China, but no clear association was observed in either of the tag single nucleotide polymorphisms of NKX2-1.

关键词： NKX2-1 papillary thyroid carcinoma the Han population of Northern China association

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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

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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

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of the agglomeration of crystals in the reactive crystallization of 5-(difluoromethoxy)-2-mercapto-1

Yongli WANG, Shuyuan MA, Xiaodong Lü, Chuang XIE

《化学科学与工程前沿（英文）》 2012年第6卷第4期页码 423-431 doi: 10.1007/s11705-012-1211-7

摘要： 5-(Difluoromethoxy)-2-mercapto-1 -benzimidazole (DMB) was precipitated by adding acetic acid to the DMB sodium salt solution. The spherical agglomeration of DMB during the reactive crystallization in a batch crystallizer was monitored by real-time Particle Video Microscope (PVM). We found that the low feeding rate of acetic acid, high crystallization temperature, low agitation rate or adding seed crystal can facilitate the formation of spherical agglomerates. By using a simple model, the mean crystal agglomerate size of DMB thus predicted is generally in agreement with the experimental data. In addition, the crystallization process of DMB was optimized by a new control strategy of supersaturation to avoid disadvantages brought by agglomeration.

关键词： 5-(difluoromethoxy)-2-mercapto-1H-benzimidazole (DMB) reactive crystallization agglomeration feeding rate crystallization temperature agitation rate

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What can be taught in architectural design? —

Xing RUAN

《结构与土木工程前沿（英文）》 2010年第4卷第4期页码 450-455 doi: 10.1007/s11709-010-0098-y

摘要： 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.

关键词： architectural design teaching parti and poché

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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

《化学科学与工程前沿（英文）》 2011年第5卷第1期页码 122-125 doi: 10.1007/s11705-010-0533-6

摘要： 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.

关键词： soybean Aspergillus niger Aspergillus flavus solid-state fermentation extraction of oil

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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

《环境科学与工程前沿（英文）》 2009年第3卷第2期页码 194-199 doi: 10.1007/s11783-009-0018-3

摘要： 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).

关键词： terminal restriction fragment length polymorphism (T-RFLP) bacterial community structure marine microbial diversity HhaI MspI

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标题作者时间类型操作

Kinetic roughening transition and missing regime transition of melt crystallized polybutene-1 tetragonal

Motoi YAMASHITA

期刊论文

Lamellar thickness transition of melt-crystallized polybuten-1 tetragonal phase: configurational change

Motoi YAMASHITA

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

Synthesis of depsipeptides from

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

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

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

Synthesis of