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Enhanced production of poly-3-hydroxybutyrate by recombinant Escherichia coli containing NAD kinase and phb CAB operon

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Science China Chemistry 2016年第11期59卷 1390-1396页

作者： Shaoqin Zhang Lei Fang Zhengjun Li yingying guo guo-Qiang Chen Center for Synthetic and Systems Biology School of Life Science Tsinghua-Peking Center for Life SciencesTsinghua University Beijing Key Laboratory of Bioprocess College of Life Science and Technology Beijing University of Chemical Technology Center for Nano and Micro Mechanics Tsinghua University

With the help of Tn5 transposon technique, gene yfj B encoding NAD kinase in Escherichia coli(E. coli) was inserted into chromosome of recombinant E. coli polyhydroxybutyrate(PHB) containing PHB synthesis operon integrated in the host genome. After successful transposition of an extra yfj B gene copy into genome, the selected recombinant named E. coli PHBTY4 showed stronger NAD kinase activity than that of E. coli PHB. Shake flask studies suggested that both cell dry weight and PHB accumulation were significantly increased in E. coli PHBTY4 compared with that of the control. E. coli PHBTY4 produced approximately 23 g/L PHB compared with its control which synthesized only 10 g/L PHB when grown under the same conditions in a 6 L fermentor after 32 h of cultivation. In addition, E. coli PHBTY4 maintained high genetic stability during the cultivation processes. These results revealed a practical method to construct genetically stable strains harboring extra NAD kinase gene to enhance NADP(H)-dependent bio-reactions.

关键词： PHB polyhydroxyalkanoates Tn5 transposon NAD kinase Escherichia coli

Synthetic biology of microbes synthesizing polyhydroxyalkanoates (PHA)

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Synthetic and Systems Biotechnology 2016年第4期1卷 236-242页

作者： guo-Qiang Chen Xiao-Ran Jiang yingying guo School of Life Sciences Tsinghua UniversityBeijing 100084China Center for Synthetic and Systems Biology Tsinghua UniversityBeijing 100084China Tsinghua-Peking Center for Life Sciences Tsinghua UniversityBeijing 100084China Center for Nano and Micro Mechanics Tsinghua UniversityBeijing 100084China MOE Key Lab of Industrial Biocatalysis Dept Chemical EngineeringTsinghua UniversityBeijing 100084China

Microbial polyhydroxyalkanoates(PHA)have been produced as bioplastics for various *** the support of China National Basic Research 973 Project,we developed synthetic biology methods to diversify the PHA structures into homo-,random,block polymers with improved properties to better meet various application *** the same time,various pathways were assembled to produce various PHA from glucose as a simple carbon *** the end,Halomonas bacteria were reconstructed to produce PHA in changing morphology for low cost production under unsterile and continuous *** synthetic biology will advance the PHA into a bio-and material industry.

关键词： Polyhydroxyalkanoates 973 Bioprocesses Pathways

低分子质量岩藻聚糖硫酸酯的分离纯化、结构表征及体外抗氧化活性

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维普期刊数据库

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食品科学 2025年第2期46卷 50-56页

作者：于凡郭莹莹李娜代心悦朱文嘉姚琳江艳华王联珠大连工业大学食品学院辽宁大连116000 中国水产科学研究院黄海水产研究所山东青岛266071 农业农村部水产品质量安全检测与评价重点实验室山东青岛266071

以裙带菜岩藻聚糖硫酸酯为原料,采用自由基氧化降解法及强阴离子交换色谱技术,制备纯化得到低分子质量岩藻聚糖硫酸酯F-1和F-2。通过分子排阻色谱、高效液相色谱、红外光谱和核磁共振技术对F-1和F-2的化学组成和结构特征进行解析,探究... 详细信息

以裙带菜岩藻聚糖硫酸酯为原料,采用自由基氧化降解法及强阴离子交换色谱技术,制备纯化得到低分子质量岩藻聚糖硫酸酯F-1和F-2。通过分子排阻色谱、高效液相色谱、红外光谱和核磁共振技术对F-1和F-2的化学组成和结构特征进行解析,探究低分子质量岩藻聚糖硫酸酯的抗氧化构效关系。结果表明:F-1和F-2主要由岩藻糖和半乳糖组成,分子质量分别为2790 Da和23510 Da,硫酸基质量分数分别为(27.05±0.95)%和(34.73±0.08)%,糖醛酸质量分数分别为(15.39±0.33)%和(6.76±0.38)%。F-1和F-2的糖苷键构型均为α型,且具有一定程度的乙酰化和硫酸化。综合比较不同质量浓度F-1和F-2的体外抗氧化活性,发现二者均可清除1,1-二苯基-2-三硝基苯肼自由基和2,2’-联氮-二(3-乙基苯并噻唑-6-磺酸)阳离子自由基,对铁氰化钾具有一定的还原能力,并呈现剂量依赖性。分子质量较小的F-1糖链上的糖醛酸、半乳糖含量相对较高,在相同剂量条件下其抗氧化活性优于F-2。该研究结果可为将低分子质量岩藻聚糖硫酸酯作为一种优良的天然抗氧化物质应用于保健食品和化妆品等领域提供理论依据。

关键词：低分子质量岩藻聚糖硫酸酯化学组成结构特征抗氧化活性

Surface modification of CeO_(2-x) nanorods with Sn doping for enhanced nitrogen electroreduction

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Journal of Energy Chemistry 2023年第12期87卷 400-407,I0011页

作者： Yuhang Xiao Xiaohong Tan yingying guo Jianpo Chen Weidong He Hao Cui Chengxin Wang School of Materials Science and Engineering Sun Yat-sen UniversityGuangzhou 510275GuangdongChina The Key Laboratory of Low-Carbon Chemistry&Energy Conservation of Guangdong Province Sun Yat-sen UniversityGuangzhou 510275GuangdongChina

While the electrochemical nitrogen reduction reaction(NRR) represents a prospective blueprint for environmentally renewable ammonia generation,it has yet to overcome the limitations of weak activity and inferior *** this regard,surface modification tactic was constructed to markedly enhance the activity and selectivity via introducing Sn atoms into the surface of defective cerium oxide(denoted as Sn-CeO_(2-x)) as the active and robust electrocatalyst for NRR under benign *** introduction of Sn atoms in CeO_(2-x)can not only inhibit the HER activity of the catalyst but also modulate the electronic structure of ceria and optimize N-Ce interaction,thus enhancing NRR activity and *** all previous CeO_(2)-based NRR catalysts,this catalyst has demonstrated an ammonia yield rate of 41.1 μg mg_(cat)^(-1) h^(-1) and an exceptional Faradic efficiency of 35.3%.This work presents a viable approach for the development of advanced NRR electrocatalysts.

关键词： Ceria-based materials Nitrogen reduction reaction Sn-doping Surface modification Electrocatalysis

Data mining-based study on sub-mentally healthy state among residents in eight provinces and cities in China

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Journal of Traditional Chinese Medicine 2014年第4期34卷 511-517页

作者： Hongmei Ni Xuming Yang Chengquan Fang yingying guo Mingyue Xu Yumin He College of Basic Medicine Shanghai University of Traditional Chinese Medicine College of Acupuncture and Massage Shanghai University of Traditional Chinese Medicine Department of Gastroenterology Yueyang Hospital of Integrated Chinese Medicine and Western Medicineaffiliated to Shanghai University of Traditional Chinese Medicine

OBJECTIVE: To apply data mining methods to research on the state of sub-mental health among residents in eight provinces and cities in China and to mine latent knowledge about many conditions through data mining and analysis of data on 3970 sub-mentally healthy individuals selected from 13385 relevant question ***: The strategic tree algorithm was used to identify the main mani festations of the state of sub-mental health. The backpropogation artificial neural network was used to analyze the main mani festations of sub-healthy mental states of three different degrees. A sub-mental health evaluation model was then established to achieve predictive ***: Using classifications from the Scale of Chinese Sub-healthy State, the main manifestations of sub-mental health selected using the strate gictree were F1101(Do you lack peace of mind?),F1102(Are you easily nervous when something comes up?), and F1002(Do you often sigh?). The relative intensity of manifestations of sub-mental health was highest for F1101, followed by F1102,and then F1002. Through study of the neural network, better differentiation could be made between moderate and severe and between mild and severe states of sub-mental health. The differentiation between mild and moderate sub-mental health states was less apparent. Additionally, the sub-mental health state evaluation model, which could be used to predict states of sub-mental health of different individuals, was established using F1101, F1102, F1002, and the mental self-assessment totals ***: The main manifestations of the state of sub-mental health can be discovered using data mining methods to research and analyze the latent laws and knowledge hidden in research evidence on the state of sub-mental health. The state of sub-mental health of different individuals can be rapidly predicted using the model established *** can provide a basis for assessment and intervention for sub-mental health. It can also

关键词： Questionnaires Mental health Data mining Strategictree Artificial neural network

Dissolved organic matter-mediated reduction of ionic Au(Ⅲ)to elemental Au nanoparticles and their growth to visible granules

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Chinese Chemical Letters 2020年第7期31卷 1970-1973页

作者： Ying Chen yingying guo Guangliang Liu Maoyong Song Yong Cai Yongguang Yin Stare Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of Sciences.Beijing 100085China University of Chinese Academy of Sciences Beijing 100085China Laboratory of Environmental Nanotechnology and Health Effect Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Department of Chemistry and Biochemistry Florida International UniversityMiamiFL 33199United States Institute of Environment and Health Jianghan UniversityWuhan430056China

The biogeochemical transformation of gold(Au),*** dissolution and re-precipitation,is critical in supergene transport of Au and formation of Au *** biogenic reduction,the formation Au granules can also be driven by chemical *** studies have showed the fo rmation of Au nanoparticles(AuNPs)from ionic Au(Ⅲ)can be mediated by dissolved organic matter under *** this letter,we further demonstrated that these AuNPs can further slowly(in years)grow into visible Au *** sized nano-flower and fractal dendrite-like branched gold structures(from tens of nanometres to over 100μm)were observed in the Au granule *** growth of AuNPs into visible Au granules may play a critical role in the supergene mineralization and enrichment of secondary Au and drive the biogeochemical cycle of Au.

关键词： Gold granule Gold nanoparticle Dissolved organic matter Photochemical reduction Mineralization

Research of NO_(2) vertical profiles with look-up table method based on MAX-DOAS

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Chinese Physics B 2022年第1期31卷 332-338页

作者： yingying guo Suwen Li Fusheng Mou Hexiang Qi Qijin Zhang Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation School of Physics and Electronic InformationHuaibei Normal UniversityHuaibei 235000China

Obtaining the vertical distribution profile of trace gas is of great significance for studying the diffusion procedure of air *** this article,a look-up table method based on multi-axis differential optical absorption spectroscopy(MAX-DOAS)technology is established for retrieving the tropospheric NO_(2) vertical distribution *** method retrieves the aerosol extinction profiles with minimum cost ***,the aerosol extinction profiles and the atmospheric radiation transfer model(RTM)are employed to establish the look-up table for retrieving the NO_(2) vertical column densities(VCDs)and *** measured NO_(2) differential slant column densities(DSCDs)are compared with the NO_(2) DSCDs simulated by the atmospheric RTM,and the NO_(2) VCDs,the weight factor of NO_(2) in the boundary layer,and the boundary layer height are obtained by the minimization *** look-up table is established to retrieve NO_(2) VCDs based on MAX-DOAS measurements in Huaibei area,and the results are compared with the data from Copernicus Atmospheric Monitoring Service(CAMS)*** is found that there are nearly consistent and the correlation coefficient R2 is more than *** results show that this technology provides a more convenient and accurate retrieval method for the stereoscopic monitoring of atmospheric environment.

关键词： multi-axis differential optical absorption spectroscopy look-up table method the cost function NO_(2)vertical profile

Intercalation assisted liquid phase production of disulfide zirconium nanosheets for efficient electrocatalytic dinitrogen reduction to ammonia

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Green Energy & Environment 2023年第4期8卷 1174-1184页

作者： Yangshuo Li Huiyong Wang Bing Chang yingying guo Zhiyong Li Shamraiz Hussain Talib Zhansheng Lu Jianji Wang Henan Key Laboratory of Green Chemistry Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan453007China School of Environment Henan Key Laboratory for Environmental Pollution ControlKey Laboratory for Yellow River and Huai River Water Environment and Pollution ControlMinistry of EducationHenan Normal UniversityXinxiangHenan453007China School of Physics Henan Normal UniversityXinxiangHenan453007China

Disulfide zirconium(ZrS_(2)) is a two-dimensional(2D) transition metal disulfide and has given rise to extensive attention because of its distinctive electronic structure and ***,mass production of high quality of ZrS_(2)nanosheets to realize their practical application remains a ***,we have successfully exfoliated the bulk ZrS_(2)powder with the thickness of micron into single and few-layer nanosheets through liquid-phase exfoliation in N-methylpyrrolidone(NMP) assisted via aliphatic amines as *** is found that the exfoliation yield is as high as 27.3%,which is the record value for the exfoliation of ZrS_(2)nanosheets from bulk ZrS_(2)powder,and 77.1% of ZrS_(2)nanosheets are 2-3 *** molecular geometric size and aliphatic amine basicity have important impact on the ***,the ZrS_(2)nanosheets have been used as catalyst in the electrocatalytic dinitrogen reduction with the NH3yield of 57.75 μg h^(-1)mg_(cat.)^(-1),which is twice that by ZrS_(2)nanofibers reported in literature and three times that by the bulk ZrS_(2)***,the liquid phase exfoliation strategy reported here has great potential in mass production of ZrS_(2)nanosheets for high activity electrocatalysis.

关键词： Disulfide zirconium Liquid-phase exfoliation Aliphatic amines Electrocatalytic dinitrogen reduction Ammonia

Hydroxyl radical formation upon dark oxidation of reduced iron minerals: Effects of iron species and environmental factors

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Chinese Chemical Letters 2019年第12期30卷 2241-2244页

作者： Ailing Zhu yingying guo Guangliang Liu Maoyong Song Yong Liang Yong Cai Yongguang Yin Institute of Environment and Health Jianghan UniversityWuhan 430056China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Laboratory of Environmental Nanotechnology and Health Effect Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Department of Chemistry and Biochemistry Florida International UniversityMiamiFL 33199United States

Dark formation of hydroxyl radical upon oxidation of reduced iron minerals plays an important role in the degradation and transformation of organic and inorganic ***,we compared the hydroxyl radical formation from various reduced iron minerals at different redox conditions.·OH production was generally observed from the oxidation of reduced iron minerals,following the order:mackinawite(FeS)>reduced nontronite(iron-bearing smectite clay)> pyrite(FeS2)> side rite(FeCO3).Structural Fe^2+ and dissolved O2 play critical roles in ·OH production from reduced iron minerals.·OH production increases with decreasing pH,and Cl^-has little effect on this *** importantly,dissolved organic matter significantly enhances ·OH production,especially under O2 purging,highlighting the importance of this process in ambient *** sunlight-independent pathway in which ’OH forms during oxidation of reduced iron minerals is helpful for understanding the degradation and transformation of various inorganic and organic pollutants in the redox-fluctuation environments.

关键词： Reduced iron minerals Hydroxyl radical Dark oxidation Mackinawite Dissolved organic matter