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L-asparaginase production by mangrove derived Bacillus cereus MAB5:optimization by response surface methodology

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Asian Pacific Journal of Tropical Medicine 2011年第6期4卷 486-491页

作者： Thenmozhi c Sankar R Karuppiah V Sampathkumar P centre of Advanced Study in Marine Biology Faculty of Marine Sciences Annamalai University Parangipettai-608 502Tamil NaduIndia

Objective:To isolate marine bacteria,statistically optimize them for maximum asparaginase ***:In the present study,statistically based experimental designs were applied to maximize the production of L-asparaginase from bacterial strain of Bacillus cereus（***） MAB5（HQ675025） isolated and identified by 16S rDNA sequencing from mangroves rhizosphere ***:Plackett-Barman design was used to identify the interactive effect of the eight variables *** extract,soyabean meal,glucose,magnesium sulphate,KH2PO4,wood chips,aspargine and sodium *** the variables are denoted as numerical factors and investigated at two widely spaced intervals designated as -1（low level） and +1（high level）. The effect of individual parameters on L-asparaginase production was *** meal,aspargine,wood chips and sodium chloride were found to be the significant among eight *** maximum amount of L-asparaginase produced（51.54 IU/mL） from the optimized medium containing soyabean meal（6.282 8 g/L）,aspargine（5.5 g/L）,wood chips（1.383 8 g/L） and Nacl（4.535 4 g/L）.conclusions:The study revealed that,it is useful to produce the maximum amount of L-asparaginase from *** MAB5 for the treatment of various infections and diseases.

关键词： L-asparaginase Bacillus cereus Mangroves Plackett-Barman design central composite design

Visual observations of 1998 Leonids in Delingha and their preliminary analysis

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chinese Science Bulletin 2000年第23期45卷 2142-2147页

作者： M.c.de Lignie M.Langbroek Dutch Meteor Society Jan Steenlaan 46NL-2251Jh Voorschotenthe NetherlandsDutch Meteor SocietyJan Steenlaan 46NL-2251Jh Voorschotenthe Netherlands

On the basis of the observational data obtained by the Sino-Dutch Joint Leonids Observation Team at Delingha Station of Purple Mountain Observatory from Nov. 13 to 18, 1998, and those obtained in other places of china during the same period, the distribution characteristics of the 1998 Leonids are analyzed and a three-layer structure of the meteoric shower encountered by the Earth is proposed.

关键词： Leonids ZHR mass distribution.

GO/MgO/Mg interface mediated strengthening and electromagnetic interference shielding in AZ31 composite

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Journal of Magnesium and Alloys 2023年第10期11卷 3800-3814页

作者： Z.Y.Xu c.F.Fang c.J.Li R.Wang X.P.Zhang J.Tan Y.M.Wang Key Laboratory of Solidification control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China college of Materials Science and Engineering Chongqing UniversityChongqing 400045China Key Laboratory of Materials Modification by Laser Ion and Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian 116023China

More requirements of electromagnetic interference(EMI) shielding performance are put forward for lightweight structural materials due to the development of aerospace and 5G communications. Herein, graphene oxide(GO) decorated with SnO_(2) coating is introduced as reinforcement into AZ31 Mg alloy. During the smelting process, the MgO layer is in situ gernerated at interface between GO and the molten Mg alloy matrix by consuming SnO_(2). In the solid state, such kind of interface structure can improve the GO-Mg interface bonding intensity,also significantly generate stacking faults. The AZ31 composite reinfoced by trace modified GO(0.1 wt%) exhibits high ultimate strength and almost the same elongation with AZ31 alloy. compared with AZ31 alloy, the yield strength and ultimate tensile strength of composite are increased by 33.5% and 23.7%, respectively. Meanwhile, the multi-level electromagnetic reflection from the multi-layer structure of GO and the interface polarization caused by the MgO mid-layer can significantly improve EMI shielding performance. The appropriate interface design strategy achieves the effect of “two birds with one stone”.

关键词： Metal-matrix composites Mechanical properties EMI shielding Microstructures

combining machine learning with 3D-cFD modeling for optimizing a DISI engine performance during cold-start

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能源与人工智能(英文) 2021年第3期5卷 298-315页

作者： Arun c.Ravindran Sage L.Kokjohn Department of Mechanical Engineering University of Wisconsin-MadisonMadisonWI 53706USA

This work presents a methodology for using machine learning(ML)techniques in combination with 3D computa-tional fluid dynamics(cFD)modeling to optimize the cold-start fast-idle phase of a gasoline direct injection spark ignition(DISI)*** optimization process implies the identification of the range of operating parameters,that will ensure the following criteria under cold-start conditions:(1)a fixed IMEP of 2 bar(BMEP of 0 bar),(2)a stoichiometric exhaust equivalence ratio(based on carbon-to-oxygen atoms)to ensure the efficient operation of the after-treatment system,(3)enough exhaust heat flux to ensure a rapid light-offof the after-treatment system,and(4)reduced NOx and Hc emissions.A total of six operating parameters will be identified as having a signifi-cant influence on cold-start engine *** parameters are associated with the fuel injection strategy(end of the second injection,injection pressure,and fuel mass);combustion strategy(spark timing,spark energy);and intake airflow(intake manifold pressure).Performing an optimization study exclusively using multi-cycle(at least 3 cycles)3D cFD simulations would be an arduous *** example,to achieve an exhaust equivalence ratio of 1 and an IMEP of 2 bar,multiple iterations would be required for fuel mass(to account for film forma-tion),intake manifold pressure(to ensure enough air in-cylinder),and spark timing(to ensure the fixed load).This process would be more convoluted and expensive with the addition of constraints for exhaust heat flux and emissions.A promising approach to tackling such a complicated optimization process is to employ the concept of machine learning,which demands a database formed by the six operating parameters mentioned *** current work will demonstrate a strategy of combining cFD modeling with advanced Gaussian Process Regres-sion(GPR)-based ML models to make predictions about DISI cold-start behavior with acceptable accuracy and a substantially reduced computation

关键词： injection performance enough

Sediment load calculations from point measurements in sand-bed rivers

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International Journal of Sediment Research 2015年第1期30卷 1-12页

作者： Seema c.SHAH-FAIRBANK Pierre Y JULIEN Department of civil Engineering California State Polytechnic University Department of civil and Environmental Engineering Colorado State University

Point velocity and suspended sediment concentration measurements are used to calculate the total sediment discharge in sand-bed *** with the Series Expansion of the Modified Einstein Point Procedure（SEMEPP） depend on grain diameter d;and settling velocity ω,flow depth h,shear velocity u*,and sampling depth h;.This procedure extends the applicability of the Modified Einstein Procedure（MEP） by using point sediment concentration and velocity *** procedure is tested using the laboratory data from coleman,and field measurements from the Enoree,Middle Rio Grande and Mississippi *** on 801 point measurements over 124 verticals at flow depths ranging from 0.17 m to 33.5 m and sediment concentrations less than 0.1 kg L;,the accuracy of the calculations depends on u*/ω and h;/d;.Point measurement techniques like SEMEPP are well-suited when u*/ω> 5 where at least 60%of the total sediment load is measured when 90%of the flow depth is *** determination of sediment discharge from point measurements is most accurate in deep rivers when h;/d;> *** u*/ω>*** measurements are not well-suited for shallow rivers and laboratory flumes where h< 0.5 m and when u*/ω< 2.

关键词： Point measurements concentration profiles Velocity profiles Total sediment load Modified Einstein Procedure

Improving metal reflectors by suppressing surface plasmon polaritons: a priori calculation of the internal reflectance of a solar cell

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Light(Science & Applications) 2013年第1期2卷 32-37页

作者： Zachary c Holman Stefaan De Wolf christophe Ballif Swiss Federal Institute of Technology Lausanne(EPFL)Institute of Microengineering(IMT)Photovoltaics and Thin-Film Electronics LaboratoryCH-2000 NeuchaˆtelSwitzerland

Imperfect internal reflectance of near-bandgap light reduces the performance of all solar cells,and becomes increasingly detrimental as absorbers become *** consider light incident on the silicon/dielectric/metal structure at the back of rear-passivated crystalline silicon solar cells with surface textures that are large enough for geometric *** calculating the absorbance in the metal as a function of the angle of incidence,we discover three results that are important for understanding and improving rear reflectors in many types of solar ***,significant parasitic absorption occurs in the metal layer in two cases:s-and p-polarized propagating modes(near-normal angles of incidence)when the dielectric thickness is adjusted to cause destructive interference of the reflected beams,and p-polarized evanescent modes(angles of incidence above the semiconductor/dielectric critical angle)that excite surface plasmon polaritons at the metal ***,the latter loss dominates;a well-designed rear dielectric passivation layer must suppress the penetration of evanescent waves to the ***,when used as an input in a simple analytical model,the average rear internal reflectance calculated by assuming a Lambertian angular distribution of light accurately predicts the total reflectance and absorbance of a solar cell.

关键词： light trapping photovoltaics plasmon silicon solar cell

comparison of ELISA and HPLc-MS methods for the determination of exenatide in biological and biotechnology-based formulation matrices

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Journal of Pharmaceutical Analysis 2019年第3期9卷 143-155页

作者： A.R. Pinho A. Fortuna A. Falcao A.c. Santos R. Seia c. Estevens F. Veiga A.J. Ribeiro Laboratory of Pharmaceutical Technology Faculty of Pharmacy University of Coimbra Polo das Ci^encias da Saúde Azinhaga de Santa Comba 3000-548 Coimbra Portugal Laboratory of Pharmacology Faculty of Pharmacy University of Coimbra Polo das Ci^encias da Saúde Azinhaga de Santa Comba 3000-548 Coimbra Portugal cNc e centre for Neuroscience and cell Biology University of Coimbra 3004-517 Coimbra Portugal REQUIMTE/LAQV Group of Pharmaceutical Technology Faculty of Pharmacy University of Coimbra Polo das Ci^encias da Saúde Azinhaga de Santa Comba 3000-548 Coimbra Portugal Laboratory of Physiology IBILI Faculty of Medicine University of Coimbra Polo das Ci^enicas da Saúde Azinhaga de Sante Comba 300-548 Coimbra Portugal Pharmaceutical Development TECNIMEDE S. A. Quinta da Cerca Caixaria 2565-187 Dois Portos Portugal I3S Instituto de Investiga鐍ao e Inova鐍ao em Sa鷇e Group Genetics of Cognitive Dysfunction IBMC e Instituto de Biologia Molecular e Celular Rua do Campo Alegre 823 4150-180 Porto Portugal

The development of biotechnology-based active pharmaceutical ingredients, such as GLP-1 analogs, brought changes in type 2 diabetes treatment options. For better therapeutic efficiency, these active pharmaceutical ingredients require appropriate administration, without the development of adverse effects or toxicity. Therefore, it is required to develop several quantification methods for GLP-1 analogs products, in order to achieve the therapeutic goals, among which ELISA and HPLc arise. These methods are developed, optimized and validated in order to determine GLP-1 analogs, not only in final formulation of the active pharmaceutical ingredient, but also during preclinical and clinical trials assessment. This review highlights the role of ELISA and HPLc methods that have been used during the assessment for GLP-1 analogs, especially for exenatide.

关键词： Type 2 diabetes Exenatide Therapeutic drug monitoring ELISA HPLc

STRANGE cONDUcTION BEHAVIOUR DURING cRYSTALLIZATION PROcESS OF AMORPHOUS IONIc cONDUcTOR IN Li_(2)O-SiO_(2)-V_(2)O_(5) SYSTEM

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chinese Physics Letters 1989年第11期6卷 511-513页

作者： cHEN Liquan c.cros XUE Rongjian WANG Lianzhong Institute of Physics Academia SinicaBeijing100080 ccAST(world laboratory) P.O.Box 8730Beijing Laboratoire de chimie du Solide du c.N.R.S France

Some peaks have been observed in plot of conductivity versus temperature for amorphous ionic conductor in Li_(2)O-SiO_(2)-V_(2)O_(5) *** has been shown from X-ray and DTA data that the amorphous ionic conductors cryst... 详细信息

关键词： conductivity amorphous

clues to predict incidental gallbladder cancer

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Hepatobiliary & Pancreatic Diseases International 2018年第2期17卷 149-154页

作者： Naeem Goussous Hadia Maqsood Kalpesh Patel Hamid Ferdosi Naseem Muhammad Anne M.Sill Gopal c.Kowdley Steven c.cunningham Department of Surgery Saint Agnes Hospital

Background: consequences of incidental gallbladder cancer(iGBc) following cholecystectomy may include repeat operation(depending on T stage) and worse survival(if bile spillage occurred), both avoidable if iGBc were suspected ***: A retrospective single-institution review was done. Ultrasound images for cases and controls were blindly reviewed by a radiologist. chi-square and Student’s t tests, as well as logistic regression and Kaplan–Meier analyses were used. A P ≤ 0.01 was considered ***: Among 5796 cholecystectomies performed 2000–2013, 26(0.45%) were iGBc cases. These patients were older(75.61 versus 52.27 years), had more laparoscopic-to-open conversions(23.1% versus3.9%), underwent more imaging tests, had larger common bile duct diameter(7.13 versus 5.04 mm) and higher alkaline phosphatase. Ultrasound imaging showed that gallbladder wall thickening(GBWT) without pericholecystic fluid(PccF), but not focal-versus-diffuse GBWT, was associated significantly with iGBc(73.9% versus 47.4%). On multivariable logistic regression analysis, GBWT without PccF, and age were the strongest predictors of iGBc. The consequences iGBc depended significantly on intraoperative bile spillage, with nearly all such patients developing carcinomatosis and significantly worse ***: Besides age, GBWT, dilated common bile duct, and elevated alkaline phosphatase, number of preoperative imaging modalities and the presence of GBWT without PccF are useful predictors of *** spillage causes poor survival in patients with iGBc.

关键词： Gallbladder cancer Incidental findings cholecystectomy Bile spillage carcinomatosis