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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第1期9卷 77-84页

作者： Dan YE Zhi-nan XU pei-lin cen Department of Chemical and Biochemical Engineering Zhejiang University Hangzhou 310027 China

Cytosine-substituted mildiomycin analogue （MIL-C） was produced effectively by supplementing cytosine into the culture of Streptoverticillium rimofaciens. In order to improve the yield of MIL-C, statistically-based experimental designs were applied to optimize the fermentation medium for S. rimofaciens ZJU 5119. Fifteen culture conditions were examined for their significances on MIL-C production using Plackett-Burman design. The Plackett-Burrnan design and one-variable-at-a-time design indicated that glucose and rice meal as the complex carbon sources, and peanut cake meal and NH4NO3 as the complex nitrogen sources were beneficial for MIL-C production in S. rimofaciens ZJU 5119. The results of further central composition design （CCD） showed that the optimal concentration of glucose, rice meal and peanut cake meal were 18.7 g/L, 64.8 g/L and 65.1 g/L, respectively. By using this optimal fermentation medium, the MIL-C concentration was increased up to 1336.5 mg/L, an approximate 3.8-fold improvement over the previous concentration （350.0 mg/L） with un-optimized medium. This work will be very helpful to the large-scale production of MIL-C in the future.

关键词： Cytosine-substituted mildiomycin analogue (MIL-C) Plackett-Burman design Response surface methodology Streptoverticillium rimofaciens Nucleoside antibiotic

High-level soluble expression of the hemA gene from Rhodobacter capsulatus and comparative study of its enzymatic properties

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2014年第5期15卷 491-499页

作者： Jia-wei LOU Li ZHU Mian-bin WU Li-rong YANG Jian-ping lin pei-lin cen Key Laboratory of Biomass Chemical Engineering of Ministry of Education Department of Chemical and Biological EngineeringZhejiang University

The Rhodobacter capsulatus hemA gene, which encodes 5-aminolevulinic acid synthase （ALAS）, was expressed in Escherichia coil Rosetta （DE3） and the enzymatic properties of the purified recombinant ALAS （RC-ALAS） were studied. Compared with ALASs encoded by hemA genes from Agrobacterium radiobacter（AR-ALAS） and Rhodobacter sphaeroides （RS-ALAS）, the specific activity of RC-ALAS reached 198.2 U/mg, which was about 31.2% and 69.5% higher than those of AR-ALAS （151.1 U/mg） and RS-ALAS （116.9 U/mg）, respectively. The optimum pH values and temperatures of the three above mentioned enzymes were all pH 7.5 and 37 ℃, respectively. Moreover, RC-ALAS was more sensitive to pH, while the other two were sensitive to temperature. The effects of metals, ethylene diamine tetraacetic acid （EDTA）, and sodium dodecyl sulfate （SDS） on the three ALASs were also investigated. The results indicate that they had the same effects on the activities of the three ALASs. SDS and metal ions such as Co^2＋, Zn^2＋, and Cu^2＋ strongly inhibited the activities of the ALASs, while Mn^2＋ exerted slight inhibition, and K^＋, Ca^2＋, Ba^2＋, Mg^2＋, or EDTA had no significant effect. The specificity constant of succinyl coenzyme A [（kcatlKm）^S-CoA] of RC-ALAS was 1.4989, which was higher than those of AR-ALAS （0.7456） and RS-ALAS （1.1699）, showing its high catalytic efficiency. The fed-batch fermentation was conducted using the recombinant strain containing the R. capsulatus hemA gene, and the yield of 5-aminolevulinic acid （ALA） achieved was 8.8 g/L （67 mmol/L） under the appropriate conditions.

关键词： 5-Aminolevulinic acid Rhodobacter capsulatus High-level expression Enzymatic properties

Lovastatin production by Aspergillus terreus in solid-state fermentation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第9期8卷 1521-1526页

作者： WEI pei-lian XU Zhi-nan cen pei-lin Institute of Biochemical Engineering Department of Chemical Engineering ＆ Bioengineering Zhejiang University Hangzhou 310027 China Department of Biochemical Engineering Zhejiang University of Science and Technology Hangzhou 310023 China

Lovastatin production by Aspergillus terreus ATCC 20542 in solid-state fermentation （SSF） was studied. Various substrates were used to evaluate the ability ofA. terreus to produce lovastatin. The results showed that either rice or wheat bran was suitable substrate for lovastatin production in SSF. The maximum yield of lovastatin （2.9 mg/g dry substrate） using rice as substrate was achieved after incubating for 11 d at the following optimized process parameters： 50%-60% initial moisture content, pH 5.5, incubation temperature 28 ℃.

关键词： Solid-state fermentation (SSF) Rice Lovastatin Aspergillus terreus

Production of laccase by Coriolus versicolor and its application in decolorization of dyestuffs: (Ⅱ) Decolorization of dyes by laccase containing fermentation broth with or without self-immobilized mycelia

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Journal of Environmental Sciences 2003年第1期15卷 5-8页

作者： lin Jian ping LIAN Wei XIA Li ming cen pei lin Department of Chemical Engineering and Bioengineering Zhejiang UniversityHangzhou 310027China.

The capability of decolorization for commercial dyes by Coriolus versicolor fermentation broth containing laccase with or without immobilized mycelium was evaluated. With cell free fermentation broth containing laccase, high decolorization ratio was achieved for acid orange 7, but not for the other dyes concerned. The immobilized mycelium was proved to be more efficient than the cell free system. All the four dyestuffs studied were found being decolourized with certain extent by immobilized mycelium. The repeated batch decolorization was carried out with satisfactory results. The experimental data showed that the continuous decolorization of wastewater from a printing and dyeing industry was possible by using the self immobilized C. Versicolor.

关键词： laccase textile dyes immobilized mycelium decolorization Coriolus versicolor

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Neuroprotective potential for mitigating ischemia-reperfusion-induced damage

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Neural Regeneration Research 2025年第8期20卷 2199-2217页

作者： Zi Ye Runqing Liu Hangxing Wang Aizhen Zuo cen Jin Nan Wang Huiqi Sun Luqian Feng Hua Yang The Clinical Medical College Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Division of Infectious Diseases Department of Internal MedicinePeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina School of Medical Imaging Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Division of Gastroenterology First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina The Second Clinical Medical College Lanzhou UniversityLanzhouGansu ProvinceChina Department of Neurosurgery Affiliated Hospital of Guizhou Medical UniversityGuiyangGuizhou ProvinceChina

Reperfusion following cerebral ischemia causes both structural and functional damage to brain tissue and could aggravate a patient's condition;this phenomenon is known as cerebral ischemia-reperfusion *** studies have elucidated the neuroprotective role of the sirtuin protein family(Sirtuins)in modulating cerebral ischemia-reperfusion ***,the potential of utilizing it as a novel intervention target to influence the prognosis of cerebral ischemia-reperfusion injury requires additional *** this review,the origin and research progress of Sirtuins are summarized,suggesting the involvement of Sirtuins in diverse mechanisms that affect cerebral ischemia-reperfusion injury,including inflammation,oxidative stress,blood-brain barrier damage,apoptosis,pyroptosis,and *** therapeutic avenues related to Sirtuins that may improve the prognosis of cerebral ischemia-reperfusion injury were also investigated by modulating Sirtuins expression and affecting representative pathways,such as nuclear factor-kappa B signaling,oxidative stress mediated by adenosine monophosphate-activated protein kinase,and the forkhead box *** review also summarizes the potential of endogenous substances,such as RNA and hormones,drugs,dietary supplements,and emerging therapies that regulate Sirtuins *** review also reveals that regulating Sirtuins mitigates cerebral ischemia-reperfusion injury when combined with other risk *** Sirtuins show promise as a potential target for the treatment of cerebral ischemiareperfusion injury,most recent studies are based on rodent models with circadian rhythms that are distinct from those of humans,potentially influencing the efficacy of Sirtuinstargeting drug ***,this review provides new insights into the role of Sirtuins in the pathology and treatment of cerebral ischemia-reperfusion injury.

关键词： apoptosis autophagy blood-brain barrier dietary supplements drug hormones inflammation neuroprotection oxidative stress prognosis pyroptosis reperfusion injury risk factors RNA therapeutics

Characteristics and Weldability of Resistance Plug Welding of Dissimilar Steels

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Journal of Wuhan University of Technology(Materials Science) 2023年第6期38卷 1463-1471页

作者： cen Yaodong CHEN lin MA Xiao School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014010China

TRIP980 high-strength steel plate/SPCC low-carbon steel plate were welded by RPW. The key factors such as size and material of filler were studied, and the structure, fusion ratio and mechanical properties of the RPW joint were analyzed. The experimental results show that the calculation formulas of the length and diameter of the filler were designed reasonably. Q235 as a filler for RPW of TRIP980 high-strength steel plate/SPCC low-carbon steel plate is suitable according to schaeffler organization chart. The deposited metal of RPW joint is in the shape of “spool”,and the base metal and cap of deposited metal are alternately combined. The deposited metal has the characteristics of “locking” as rivets, which is beneficial to the improvement of mechanical properties of RPW joint. The nugget of RPW joint is uniform without deviates. TRIP980 high-strength steel plate, SPCC low-carbon steel plate, and filler were metallurgically bonded in the RPW joint.

关键词： dissimilar steel resistance plug welding nugget

A Lightweight Compact Lithium-Ion Battery Thermal Management System Integratable Directly with EV Air Conditioning Systems

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Journal of Thermal Science 2022年第6期31卷 2363-2373页

作者： lin Bichao cen Jiwen JIANG Fangming Laboratory of Advanced Energy Systems Guangzhou Institute of Energy ConversionChinese Academy of SciencesGuangzhou510640China CAS Key Laboratory of Renewable Energy Guangzhou 510640China Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China

This paper discusses an improved thermal management system to ameliorate the performance of lithium-ion battery storage systems for electric vehicles(EVs) applications. A compact and lightweight cold plate is designed and fabricated to fit 18650-type lithium-ion batteries, using aluminum-finned copper tubes. A dynamic temperature PID(proportional, integral, differential) control algorithm for electronic expansion valves is developed to study using EV air conditioning refrigerant, R134a, to control battery modules’ temperature with this compact and lightweight thermal management system. The experimental results show that the proposed battery thermal management system can effectively control the battery module’s temperature. In addition, during 1C discharge, when the PID temperature algorithm control scheme is used, the maximum temperature difference across the battery module peaks at less than 4℃, and the maximum temperature within the battery module is less than 36℃.

关键词： electric vehicles air conditioning system battery thermal management finned tube two-phase flow

A novel radial cable for restraining tensile failure in steep fill–rock interfaces

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Journal of Mountain Science 2019年第7期16卷 1715-1730页

作者： HUANG Da LI pei-ji cen Duo-feng School of Civil and Transportation Engineering Hebei University of Technology

It is quite common for fill slopes such as embankments and airport foundations to be constructed in mountainous *** fill–rock interfaces in such areas undergo tensile failure owing to differences in the stiffness values and tensile strengths of the soil and hard *** this study,a new anchor system,termed“radial cable,”is proposed to increase the pullout capacity of cables in the fill;this in turn helps control tensile deformation in the fill slope along the *** a radial cable,the steel ropes of a conventional cable are equally and symmetrically separated into three sub-cables(a central sub-cable and two branch sub-cables)with a radial distribution starting from the position of the ***,each of the sub-cables is fixed in the fill using short U-shaped rigid rods along the cable length and a rigid baffle at its end to further increase pullout *** and numerical uplift tests were conducted to analyze the pullout capacity and anchoring behavior of the radial cables in soil to study the effect of *** reinforcement effect of the radial cables was also examined using a case study.

关键词： Fill slope Fill–rock interface Tensile failure Radial cable Pullout capacity

Synthesis and enhanced luminescence properties of double perovskite NaLa0.95-xYxEu0.05MgWO6 phosphors

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Rare Metals 2020年第8期39卷 895-901页

作者： Jing Zhang Jia-lin Shen Nai-cen Xu Nanjing center China Geological SurveyNanjing 210016China Supervision and Testing center of East China Mineral Resources of the Ministry of Land and ResourcesNanjing 210016China

Double perovskite Na(La,Y)MgWO6:Eu3+phosphors were obtained by the sol-gel method.X-ray diffractometer(XRD)patterns,scanning electron microscopy(SEM)images and photoluminescence properties were carried out to study the effect of polyethylene glycol(PEG).Enhanced optical properties were obtained by adding 3 wt%PEG under the excitation of 395 nm.Y3+with smaller radius was selected to substitute La3+in this host to decrease the symmetry and further enhance the luminescence *** Y3+concentration increasing,Na2WO4 and Y30W8O69 phases came *** emission spectra showed different shapes,and the emission intensity was enhanced by doping Y3+.Under the excitation of 395 and 465 nm,the emission intensity reached the *** Commission Internationale de L’Eclairage(CIE)coordinates of the phosphors were on the edge of the CIE diagram,illustrating that this double perovskite phosphor showed good color *** luminescence properties showed that the synthesized phosphors had great potential in solid-state lighting.

关键词： Double perovskite Structure evolution Phosphors White light emitting diodes

Environmental Characteristics of Groundwater:an Application of PCA to Water Chemistry Analysis in Yulin

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Journal of China University of Mining and Technology 2007年第1期17卷 73-77页

作者： DONG Dong-lin WU Qiang ZHANG Rui SONG Ying-xia CHEN Shu-ke LI pei LIU Shou-qiang BI cen-cen LV Zhen-qi HUANG Song-lin State Key Lab of Coal Resources and Safe Mining China University of Mining ＆ Technology Beijing 100083 China

For our investigation into the water quality in Yulin city, we collected 76 typical water samples to be tested for particle quality. By applying a Romani type classification method the groundwater of Yulin city was classified into nine categories by type, i.e., Ca-HCO3, Na-HCO3, Na-HCO3-SO4-Cl, Na-HCO3-SO4, Na-Cl, Na-Cl-HCO3, Na-Ca- HCO3, Ca-Cl-HCO3 and Ca-HCO3-SO4-Cl. A principal component analysis was carried out in order to analyze the groundwater environment. From this analysis we considered that the information collected could be represented by 21 indices from which we extracted seven principal components, which, respectively, accounted for 37.4%, 13.0%, 8.1%, 7.2%, 6.3%, 5.9% and 4.6% of the total variation. The results show that the groundwater environment of this region is largely determined by characteristic components of the natural groundwater background. One part of the water was polluted by leaching/eluviation of solid waste generated from coal mining. Another part of the ground water was contaminated by acid mine water from the coal layer and from improper irrigation. In addition, geological and hydrogeological conditions also cause changes in the water environment.

关键词： water environment principal component analysis component loading groundwater type Yulin city