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Control of the agglomeration of crystals in the reactive crystallization of 5-(difluoromethoxy)-2-mercapto-1of 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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Design, synthesis, and antiviral properties of 2-aryl-1H-benzimidazole-4-carboxamide derivatives

Xianjin LUO, Zhonglü ZHANG, Yutian YANG, Fei XUE, Naiyun XIU, Yuanbin SHE

《化学科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 305-309 doi: 10.1007/s11705-009-0021-z

摘要： A series of new benzimidazole derivatives were designed and synthesized. Their chemical structures were testified by H NMR, infrared spectroscopy (IR), mass spectrography (MS), and elemental analysis. Their potent antiviral properties indicated the prospect of new drugs. Compound , , , , , , and were identified as novel antivirus with much better selective activity and inhibitory activity than the comparable ribavirin against Coxsackie virus B in VERO cells.

关键词： benzimidazole     coxsackie virus B3     antiviral properties    

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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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Endemicity of H9N2 and H5N1 avian influenza viruses in poultry in China poses a serious threat to poultry

Jiao HU,Xiufan LIU

《农业科学与工程前沿（英文）》 2016年 第3卷 第1期   页码 11-24 doi: 10.15302/J-FASE-2016092

摘要： The H9N2 and H5N1 avian influenza viruses (AIVs) have been circulating in poultry in China and become endemic since 1998 and 2004, respectively. Currently, they are prevalent in poultry throughout China. This endemicity makes them actively involved in the emergence of the novel lineages of other subtypes of influenza viruses, such as the well-known viruses of the highly pathogenic avian influenza (HPAI) H5N2 and the 2013 novel H7N7, H7N9 and H10N8 subtypes, thereby threatening both the poultry industry and public health. Here, we will review briefly the prevalence and evolution, pathogenicity, transmission, and disease control of these two subtypes and also discuss the possibility of emergence of potentially virulent and highly transmissible AIVs to humans.

关键词： avian influenza virus     H9N2     H5N1     novel viruses     public health    

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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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The effect of preparation conditions of Pt/Al

Lei YUAN, Xiang ZHENG, Kaijiao DUAN, Hao HU, Jinggang WANG, Seong Ihl WOO, Zhiming LIU

《环境科学与工程前沿（英文）》 2013年 第7卷 第3期   页码 457-463 doi: 10.1007/s11783-013-0512-5

摘要： Selective catalytic reduction of NO by H in the presence of oxygen has been investigated over Pt/Al O catalysts pre-treated under different conditions. Catalyst preparation conditions exert significant influence on the catalytic performance, and the catalyst pre-treated by H or H then followed by O is much more active than that pre-treated by air. The higher surface area and the presence of metallic Pt over Pt/Al O pre-treated by H or pretreated by H then followed by O can contribute to the formation of NO , which then promotes the reaction to proceed at low temperatures.

关键词： NOx reduction     Pt/Al2O3     preparation condition     H2-SCR    

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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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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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H∞ control in the frequency domain for a semi-active floor isolation system

Yundong SHI, Tracy C BECKER, Masahiro KURATA, Masayoshi NAKASHIMA

《结构与土木工程前沿（英文）》 2013年 第7卷 第3期   页码 264-275 doi: 10.1007/s11709-013-0214-x

摘要： A floor isolation system installed in a single floor or room in a fixed base structure is designed to protect equipment. With this configuration, the input motions to the floor isolation from the ground motions are filtered by the structure, leaving the majority of the frequency content of the input motion lower than the predominant frequency of the structure. The floor isolation system should minimize the acceleration to protect equipment; however, displacement must also be limited to save floor space, especially with long period motion. Semi-active control with an control was adopted for the floor isolation system and a new input shaping filter was developed to account for the input motion characteristics and enhance the effectiveness of the control. A series of shake table tests for a semi-active floor isolation system using rolling pendulum isolators and a magnetic-rheological damper were performed to validate the control. Passive control using an oil damper was also tested for comparison. The test results show that the control effectively reduced acceleration for short period motions with frequencies close to the predominant frequency of the structure, as well as effectively reduced displacement for long period motions with frequencies close to the natural frequency of the floor isolation system. The control algorithm proved to be more advantageous than passive control because of its capacity to adjust control strategies according to the different motion frequency characteristics.

关键词： semi-active     floor isolation     H∞ control     MR damper     shaping filter     shaking table test    

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1,5-戊二胺的细菌合成及应用 Review

马伟超, 陈可泉, 李艳, 郝宁, 王昕, 欧阳平凯

《工程（英文）》 2017年 第3卷 第3期   页码 308-317 doi: 10.1016/J.ENG.2017.03.012

摘要：

1,5-戊二胺是一种广泛分布于原核和真核生物中的具有多种生物活性的天然多胺，正日益成为一种重要的工业化学品，并在多个领域展现出广泛的应用前景，特别是作为单体用于合成生物基聚酰胺。基于1,5-戊二胺的聚酰胺5X 具有优异的性能和环境友好特性，因而有广泛的应用前景。本文总结了近期关于1,5-戊二胺在细菌中的生物合成、代谢及生理学功能，着重介绍了1,5-戊二胺在大肠杆菌的代谢调控机制。文中还综述了微生物发酵法和全细胞催化法生产1,5-戊二胺的进展及1,5-戊二胺的分离纯化方法。此外，对1,5-戊二胺在生物基聚酰胺合成中的应用进行了总结，并对利用可再生资源生产1,5-戊二胺进行了展望和对以后的研究提出了建议。

关键词： 1     5-戊二胺     代谢     细菌生产     生物基聚酰胺     PA 5X    

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标题 作者 时间 类型 操作

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

Yongli WANG, Shuyuan MA, Xiaodong Lü, Chuang XIE

期刊论文

Design, synthesis, and antiviral properties of 2-aryl-1H-benzimidazole-4-carboxamide derivatives

Xianjin LUO, Zhonglü ZHANG, Yutian YANG, Fei XUE, Naiyun XIU, Yuanbin SHE

期刊论文

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

null

期刊论文

Endemicity of H9N2 and H5N1 avian influenza viruses in poultry in China poses a serious threat to poultry

Jiao HU,Xiufan LIU

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

The effect of preparation conditions of Pt/Al

Lei YUAN, Xiang ZHENG, Kaijiao DUAN, Hao HU, Jinggang WANG, Seong Ihl WOO, Zhiming LIU

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

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

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

H∞ control in the frequency domain for a semi-active floor isolation system

Yundong SHI, Tracy C BECKER, Masahiro KURATA, Masayoshi NAKASHIMA

期刊论文

1,5-戊二胺的细菌合成及应用

马伟超, 陈可泉, 李艳, 郝宁, 王昕, 欧阳平凯

期刊论文