http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Convenient Synthesis of N-Methylpyrrolidine-2-thione and Some Thioamides
Zong, Zhi-Min,Peng, Yao-Li,Liu, Zhi-Gang,Zhou, Shi-Lu,Wu, Lin,Wang, Xiao-Hua,Wei, Xian-Yong,Lee, Chul Wee 한국화학공학회 2003 Korean Journal of Chemical Engineering Vol.20 No.2
The synthesis of thioamides and thiolactams, which are used as important organic intermediates, has attracted great attention. However, expensive reagents, severe reaction conditions and low yields of the target products made conventional methods inconvenient and economically infeasible. To overcome these disadvantages, we investigated a new process for synthesizing thioamides and thiolactams. We examine thermal reactions of CS_2 with N-methyl-2-pyrrolidinones, formylamide, acetamide and N, N-dimethylformylamide, respectively. The results show that under optimum conditions N-methylpyttolidine-2-thione and the corresponding thioamides can be obtained in good to excellent yields by the above thionation reactions.
Epidemic spreading on complex networks with general degree and weight distributions.
Wang, Wei,Tang, Ming,Zhang, Hai-Feng,Gao, Hui,Do, Younghae,Liu, Zong-Hua Published by the American Physical Society through 2014 Physical review. E, Statistical, nonlinear, and so Vol.90 No.4
<P>The spread of disease on complex networks has attracted wide attention in the physics community. Recent works have demonstrated that heterogeneous degree and weight distributions have a significant influence on the epidemic dynamics. In this study, a novel edge-weight-based compartmental approach is developed to estimate the epidemic threshold and epidemic size (final infected density) on networks with general degree and weight distributions, and a remarkable agreement with numerics is obtained. Even in complex networks with the strong heterogeneous degree and weight distributions, this approach is used. We then propose an edge-weight-based removal strategy with different biases and find that such a strategy can effectively control the spread of epidemic when the highly weighted edges are preferentially removed, especially when the weight distribution of a network is extremely heterogenous. The theoretical results from the suggested method can accurately predict the above removal effectiveness.</P>
DRM 시스템에서 사용자 중심의 콘텐츠 사용을 위한 라이센스 모델에 관한 연구
왕보현(Wang, Bo-Hyun),류종화(Liu, Zong-Hua),이병욱(Lee, Byung-Wook) 한국산학기술학회 2007 한국산학기술학회 학술대회 Vol.- No.-
기존 DRM 시스템들은 콘텐츠 저작권자의 저작권을 배타적으로 보호한다. 이에 사용자들이 DRM 으로 보호된 콘텐츠를 사용할 때는 다소 제약이 가해진다. 최근 사용자 중심의 콘텐츠 사용 요구가 확산되고 있고 이에 대한 연구가 활발히 진행되고 있다. 본 논문에서는 사용자들의 콘텐츠 사용 유형을 분류하고 그에 따른 라이센스 모델을 제안한다. 제안된 라이센스 모델에서는 사용자 식별 정보를 이용하여 허가된 사용자만이 융통적인 콘텐츠 사용을 가능하게 한다. 이러한 라이센스 모델을 통해 DRM 시스템의 저작권 보호의 기본 원칙을 제공하며 사용자에게는 융통성 있는 콘텐츠 사용을 가능하게 한다.
Ying Wang,Bu-li Cui,Dong-sheng Li,Ya-xuan Wang,Wan-xin Yu,He-hua Zong 한국기상학회 2022 Asia-Pacific Journal of Atmospheric Sciences Vol.58 No.2
A prerequisite for using isotopic techniques to study the regional water cycle of a mountainous area is to examine the stable isotopic composition of precipitation. These findings are of great significance for an in-depth understanding of water cycle processes. In this study, each precipitation event was sampled and used to investigate the characteristics of stable hydrogen and oxygen isotopes in precipitation over the Jiaolai Plain and its surrounding areas. NCEP/NCAR data was used for the wind speed and direction, relative humidity, and precipitable amount in the study area during the sampling period. The water vapor sources of the precipitation over the plain were revealed through a comparative analysis of seasonal variations in precipitation isotopes between Global Network of Isotopes in Precipitation stations located along different vapor transport paths. The results showed that the local meteoric water line was δ2H = 6.38 δ18O + 0.72, with a gradient of less than 8. This indicates that the precipitation process was affected by non-equilibrium evaporation occurring when the drops fell below the cloud base. Temperature and amount effects were observed in the δ18O of the precipitation, although the altitude effect was not significant. The water vapor source of the precipitation was predominantly controlled by the East Asian Monsoon from June to September, with the primary source being evaporation from the adjacent Pacific Ocean. The plain was controlled by the Westerlies from October through May, with the predominant vapor source being local evaporation. Water vapor from the polar region had a minimal impact. These findings can serve as the basis for studying surface water–groundwater–seawater transformations.
( Miao Wang ),( Shao Hua Wang ),( Gong Li Zong ),( Zhong Wen Hou ),( Fei Liu ),( D Joshua Liao ),( Xi Qiang Zhu ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.2
Natamycin is a widely used antifungal antibiotic. For natamycin biosynthesis, the gene pimE encodes cholesterol oxidase, which acts as a signalling protein. To confirm the positive effect of the gene pimE on natamycin biosynthesis, an additional copy of the gene pimE was inserted into the genome of Streptomyces gilvosporeus 712 under the control of the ermE* promoter (permE*) using intergeneric conjugation. Overexpression of the target protein engendered 72% and 81% increases in the natamycin production and cell productivity, respectively, compared with the control strain. Further improvement in the antibiotic production was achieved in a 1 L fermenter to 7.0 g/l, which was a 153% improvement after 120 h cultivation. Exconjugants highly expressing pimE and pimM were constructed to investigate the effects of both genes on the increase of natamycin production. However, the co-effect of pimE and pimM did not enhance the antibiotic production obviously, compared with the exconjugants highly expressing pimE only. These results suggest not only a new application of cholesterol oxidase but also a useful strategy to genetically engineer natamycin production.
Zhao-Yu Wang,Yan-Hong Bi,Min-Hua Zong 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.2
Previous studies on the lipase-mediated acylation of 6-azauridine with vinyl stearate in organic solvents revealed that while preparing a potential prodrug, 3'-Ostearoyl-6-azauridine, a lipase from Burkholderia cepacia showed high regioselectivity toward the second hydroxyl group. The most suitable reaction solvent, molar ratio of vinyl stearate to 6-azauridine, and reaction temperature were anhydrous acetone, 15:1, and 45°C, respectively. Under these conditions, the initial reaction rate, 3'-regioselectivity,and maximum substrate conversion were as high as 10.4mM/h, 86.0, and 99.0%, respectively.
( Xue Li ),( Yan-hua Liu ),( Xin Zhang ),( Chang-ming Ge ),( Ren-zhe Piao ),( Wei-dong Wang ),( Zong-jun Cui ),( Hong-yan Zhao ) 한국미생물 · 생명공학회 2017 Journal of microbiology and biotechnology Vol.27 No.3
The development and utilization of crop straw biogas resources can effectively alleviate the shortage of energy, environmental pollution, and other issues. This study performed a continuous batch test at 35°C to assess the methane production potential and volatile organic acid contents using the modified Gompertz equation. Illumina MiSeq platform sequencing, which is a sequencing method based on sequencing-by-synthesis, was used to compare the archaeal community diversity, and denaturing gradient gel electrophoresis (DGGE) was used to analyze the bacterial community diversity in rice straw, dry maize straw, silage maize straw, and tobacco straw. The results showed that cumulative gas production values for silage maize straw, rice straw, dry maize straw, and tobacco straw were 4,870, 4,032.5, 3,907.5, and 3,628.3 ml/g ·VS , respectively, after 24 days. Maximum daily gas production values of silage maize straw and rice straw were 1,025 and 904.17 ml/g ·VS, respectively, followed by tobacco straw and dry maize straw. The methane content of all four kinds of straws was > 60%, particularly that of silage maize straw, which peaked at 67.3%. Biogas production from the four kinds of straw was in the order silage maize straw > rice straw > dry maize straw > tobacco straw, and the values were 1,166.7, 1,048.4, 890, and 637.4 ml/g ·VS, respectively. The microbial community analysis showed that metabolism was mainly carried out by acetateutilizing methanogens, and that Methanosarcina was the dominant archaeal genus in the four kinds of straw, and the DGGE bands belonged to the phyla Firmicutes, Bacteroidetes, and Chloroflexi. Silage maize is useful for biogas production because it contains four kinds of straw.
( Gang Xu ),( Yu-min Wang ),( Miao-miao Ying ),( Sui-dan Chen ),( Zong-rui Li ),( Hong-lei Ma ),( Ming-hua Zheng ),( Jian Wu ),( Chunming Ding ) 대한간학회 2021 Clinical and Molecular Hepatology(대한간학회지) Vol.27 No.2
Background/Aims: Nonalcoholic steatohepatitis (NASH) is a progressive form of nonalcoholic fatty liver disease (NAFLD) characterized by hepatic steatosis, inflammation, hepatocellular injury, and fibrosis. We aimed to investigate the usefulness of a key biomarker, lipocalin-2 (LCN2), for the detection of NASH progression. Methods: A mouse NASH model was established using a high-fat diet and a high-sugar drinking water. Gene expression profile of the NASH model was analyzed using RNA sequencing. Moreover, 360 NAFLD patients (steatosis, 83; NASH, 277), 40 healthy individuals, and 87 patients with alcoholic fatty liver disease were recruited. Results: Inflammatory infiltration, focal necrosis in the leaflets, steatosis, and fibrosis were documented in the mouse liver. In total, 504 genes were differentially expressed in the livers of NASH mice, and showed significant functional enrichment in the inflammation-related category. Upregulated liver LCN2 was found to be significantly interactive with various interleukins and toll-like receptors. Serum LCN2 levels were significantly increased in NAFLD patients. Serum LCN2 levels were correlated with steatosis, intralobular inflammation, semiquantitative fibrosis score, and nonalcoholic fatty liver disease activity score. The area under the curve of serum LCN2 was 0.987 with a specificity of 100% and a sensitivity of 93.5% for NASH diagnosis, and 0.977 with almost the same specificity and sensitivity for steatosis. Conclusions: LCN2 might be involved in the transition from NAFL to NASH by mediating inflammation. Serum LCN2 levels might be a novel biomarker for the diagnosis of NASH. (Clin Mol Hepatol 2021;27:329-345)