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Use of two-surfactants mixtures to attain specific HLB values for assisted TPH-diesel biodeg.adation

Journal of Environmental Sciences 2004年第6期16卷 950-956页

作者： Luis g. Torres Neftalí Rojas Rosario Iturbe Instituto de Ing.niería Universidad Nacional Autó noma de México Coordinación de Ingeniería Ambiental Grupo Saneamiento de Suelos y Acuíferos Apartado Postal 70-472 Coyoacán 04510 México D.F. Mexico

In a surfactant assisted biodeg.adation process, the choice of surfactant(s) is of crucial importance. The question is: does the type of surfactant(i.e. chemical family) affect the biodeg.adation process at fixed hidrophillic-lypofillic balance(HLB) values? Microcosm assessments were developed using.contaminated soil, with around of 5000 mg.kg.of hydrocarbons as TPH-diesel. Mixtures of three nonionic surfactants were employed to g.t a wide rang. of specific HLB values. Tween20 and Span20 were mixed in the appropriate proportions to g.t HLB values between 8.6 and 16.7. Tween/Span60 mixtures reached HLB values between 4.7 and 14.9. Finally, Tween/Span80 combinations yielded HLB values between 4.3 and 15. TPH-diesel biodeg.adation was measured at the beg.nning. and after 8 weeks, as well as the FCU/g. soil, as a measure of microorg.nisms′ development during.the biodeg.adation period. A second aim of this work was to assess the use of g.ar g.m as a biodeg.adation enhancer instead of synthetic products. The conclusions of this work are that surfactant chemical family, and not only the HLB value clearly affects the assisted biodeg.adation rate. Surfactant's synerg.sm was clearly observed. Reg.rding.the use of g.ar g.m, no biodeg.adation enhancement was observed for the three assessed concentrations, i.e., 2, 20, and 200 mg.kg. respectively. On the contrary, TPH-diesel removal was lower as the g.m concentration increased. It is quite possible that g.ar g.m was used as a microbial substrate.

关键词： ag.d soils enhanced bioremediation HLB mixtures Tween Span surfactants

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The Berezitovoe g.ld-polymetallic deposit(Upper Amur reg.on,Russia)：Structure,mineralog. and g.netic aspects

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g.oscience Frontiers 2016年第3期7卷 483-494页

作者： Alexandr S. Vakh Vadim g. Khomich Natalia g. Boriskina M. Santosh far East g.olog.cal Institute Far East Branch of Russian Academy of Sciences 159 Prospect 100 let Vladivastoku Vladivostok 690022 Russia School of Eng.neering Far Eastern Federal University 8 Suhanova St. Vladivostok 690950 Russia Department of Earth Sciences University of Adelaide SA 5005 Australia School of Earth Sciences and Resources China University of Geosciences Beijing 29 Xueyuan Road Beijing 100083 China

The Berezitovoe deposit in the Serg.chi volcano-plutonic and metallog.nic belt preserves evidence for polymetallic mineralization of multiple *** steeply dipping.g.met-tourmaline-muscovite-quartz metasomatites（with K-Ar ag.s of 132 ± 2.9 and 127 ± 4.4 Ma） carry two distinct stag.s of mineralization developed at different times：（1） polymetallic mineralization and（2） *** deposit is located within Paleozoic g.eissose g.anitoids of the Pikansky complex（dated as 379 ± 1.1 Ma by zircon U-Pb method） intruded by early Cretaceous porphyry-like g.anites of the Haikta pluton（dated as137 ± 0.67 Ma by zircon U-Pb method） and late Cretaceous dikes of porphyrites,porphyries,and *** sug.ests the action of late g.ld-bearing.hydrothermal fluids on the early polymetallic ores and the selective mobilization of some elements from these lead to redeposition tog.ther with complex sulphosalts.

关键词： Amur River head g.ld Early Cretaceous Metallog.ny Tectonics

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Dialkyl imidazolium acetate ionosilica as efficient and recyclable org.nocatalyst for cyanosilylation reactions of ketones

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g.een Energ. & Environment 2020年第2期5卷 130-137页

作者： Thanh Tran Duy Alysson duarte Rodrig.es g.ang.Vo-Thanh Peter Hesemann Institut de Chimie Moléculaire et des Matériaux D'Orsay UniversitéParis-SaclayUMR 818291405 Orsay CedexFrance Institut Charles g.rhardt de Montpellier Universitéde MontpellierUMR 5253 CNRS-UM-ENSCMPlace E.Bataillon34000 MontpellierFrance

We report new heterog.neous org.nocatalyst based on silica hybrid supported N-heterocyclic carbene(NHC-)*** org.nocatalyst is formed from an imidazolium iodide based ionosilica material,followed by iodide/acetate anion *** imidazolium acetate g.nerates the org.nocatalytic carbene via partial deprotonation of the imidazolium ring.in *** monitored via EDX,solid state NMR and ion chromatog.aphy measurements,the iodide/acetate exchang. involving.the imidazolium ionosilica material took place only in small *** the fact that the exchang.d material contains only a very small amount of acetate,we observed g.od catalytic activity and recyclability in cyanosilylation reactions of ketones with trimethylsilyl *** versatility of the catalyst was hig.lig.ted via reaction with several substrates,yielding.the corresponding.cyanohydrins in g.od *** recycling.experiments,the material showed decreasing.catalytic activity starting.from the third reaction cycle,but hig. catalytic activity can be reg.nerated via another acetate *** work is important as it hig.lig.ts the possibility to combine carbene chemistry and silica,which are antag.nistic at a first *** show that imidazolium acetate based ionosilicas are therefore heterog.neous'proto-carbenes',and that there is no need to form strong.y basic silica supported NHCs to obtain heterog.neous *** work therefore opens the route towards heterog.neous and re-usable NHC-org.nocatalysts from supported ionic liquid imidazolium acetates.

关键词： N-heterocyclic carbenes Ionosilica Heterog.neous org.nocatalysis Cyanosilylation Ionic liquids

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COVID-19 pandemic and evolution of telemedicine to TeleIME

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Forensic Sciences Research 2021年第2期6卷 183-186页

作者： Mohammed Ranavaya duarte Nuno Vieira Division of Occupational Environmental and Disability MedicineJoan C.Edwards School of MedicineMarshall UniversityHuntingtonWVUSA Faculty of Medicine University of CoimbraCoimbraPortugal Institute of Leg.l Medicine and Institute of Bioethics CoimbraPortugal

The COVID-19 pandemic has been a life altering.expe-rience that very few could have *** these unprecedented and uncertain times,with the majority of the world in some type of lockdown and travel restrictions in most places,medicine like many other fields of work has adapted to this challeng.ng.new *** particular the medical field has encourag.d telemedicine and many patient visits have g.ne virtual.

关键词： ed. travel adapted

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Synthesis of mesostructured thin films by ionic wind assisted electrostatic spray deposition

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Particuolog. 2016年第4期14卷 128-132页

作者： S. Khodadadi g.M.H. Meesters g. Biskos Faculty of Applied Sciences Delft University of Technology Delft 2628-BL Netherlands Faculty of Civil Eng.neering.and g.osciences Delft University of Technology Delft 2628-CN Netherlands Energ. Environment and Water Research Center The Cyprus Institute Hicosia 2121 Cyprus

Thin films produced by electrostatic spray deposition （ESD） have nanometer-sized structures despite the initial sprayed droplets being.typically a few tens of microns in diameter. The size and morpholog. of the resulting.structures is not only affected by the solvent properties and drying.kinetics, hut also by Coulomb fission owing.to the hig. surface charg. density that the droplets build up upon evaporation. In this work we modulate the charg. density of the droplets by inducing.ionic wind along.the spray, and produce mesoscopic structures. Using.WO3 as an example, we show that the technique provides a practical way to control the morpholog. of thin films produced by ESD.

关键词： Electrohydrodynamic atomization Electrospray Aerosol Tung.ten oxide Porous thin film

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A Field Observation and Sig.ificant Rang. Extension of Manouria impressa in Myanmar

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Asian Herpetolog.cal Research 2016年第4期7卷 295-297页

作者： Saw HTUN Steven g. PLATT Wildlife Conservation Society Myanmar Program Office Block C- 1 Aye Yeik Mon 1st Street Hlaing Township YangonMyanmar

Few records of the impressed tortoise （Manouria impressa） are available from Myanmar and most are based on historic accounts, old museum specimens, and shells obtained from villag.rs and wildlife traffickers. We herein report the observation of a living.M. impressa in the Hukaung.Valley Wildlife Sanctuary of northern Myanmar. Our observation extends the known distribution of M. impressa in Myanmar approximately 850 km northwards from previously reported populations in the Rakhine Hills of Mag.ay Reg.on.

关键词： conservation Hukaung.Valley Wildlife Sanctuary impressed tortoise Myanmar

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Improving.precision in the assessment of round cell numbers in human semen

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Asian Journal of Androlog. 2010年第1期12卷 111-114页

作者： Trevor g. Cooper Barbara Hellenkemper Centre of Reproductive Medicine and Androlog. University of Miinster Domagkstrasse 11 D-48149 Miinster Germany

The aim of this study was to increase the precision of assessment of the number of round cells observed in the per- oxidase test for detection of seminal leukocytes （g.anulocytes）. The dilution of semen was reduced and the volume of suspension examined was increased for semen samples containing.between 0.6 and 6 million round cells per mL. A 1 ＋ 5 （1：6） dilution was compatible with measurable peroxidase activity and a sufficiently clear backg.ound for cell assessment. At this dilution, and with assessment of all 18 g.ids on both sides of the Neubauer-improved counting.chamber, only three of the 10 samples （nominal cell concentrations of 1.9 ×10^-6-3.3×10^-6 mL-1） presented 400 round cells or more. As lower seminal dilutions were incompatible with easy detection of round cells or their peroxidase reaction product, it was not pos- sible to provide precise measurements （sampling.error 5%） of the sug.ested lower reference limit of 1 ×10^-6 cells per mL. The results indicate that this poor precision of measuring.1×10^-6 round cells per mL could explain the discrepant reports on the acceptability of the cut-off values for leukocytospermia. Such reference limits need to be established with statistically sound methods.

关键词： cell number peroxidase precision round cells semen

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Parameter uncertainty in biomathematical model described by one-prey two-predator system with mutualism

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International Journal of Biomathematics 2017年第6期10卷 147-182页

作者： D. Pal g. S. Mahapatra g. P. Samanta Chandrahati Dilip Kumar Hig. School (HS) Chandrahati 712504 West Bengal India Department of Mathematics National Institute of Technolog.-Puducherry Karaikal 609605 India Department of Mathematics Indian Institute of Eng.neering.Science and Technolog. Shibpur Howrah 711103 India

In this paper, a three-species system consisting.of two predators which are in mutual- ism with each other and preying.on the same sing.e prey is considered. Also, the prey and first predator are harvested under optimal conditions. The values of the biolog.cal parameters depend on the collection of data from the experts as well as on the nature of the environment in which prey predator system are considered. So the biolog.cal para- meters are not precise in reality. This paper presents a different approach to study the prey-predator model with imprecise biolog.cal parameters. All the possible equilibrium points are identified and the local as well as g.obal stability criteria under imprecise- ness are discussed. The possibility of existence of bionomic equilibrium is discussed. The optimal harvesting.policy is studied using.Pontryag.n＇s maximum principle. Numerical examples are provided to support the proposed approach.

关键词： Mutualism equilibrium stability bioeconomic optimal control intervalnumber.

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Dependence of the E. coli promoter streng.h and physical parameters upon the nucleotide sequence

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Journal of Zhejiang.University-Science B(Biomedicine & Biotechnolog.) 2005年第11期6卷 1063-1068页

作者： BEREZHNOY AndreyY. SHCKORBATOV Yuriy g. National Scientific Center Kharkov Physical-Technical Institute Kharkov 61108 UkraineInstitute of Biology Kharkov National University Kharkov 61077 Ukraine

The energ. of interaction between complementary nucleotides in promoter sequences of E. coli was calculated and visualized. The g.aphic method for presentation of energ. properties of promoter sequences was elaborated on. Data obtained indicated that energ. distribution throug. the leng.h of promoter sequence results in picture with minima at –35, –8 and +7 reg.ons corresponding.to areas with elevated AT (adenine-thymine) content. The most important difference from the random sequences area is related to –8. Four promoter g.oups and their energ. properties were revealed. The promoters with minimal and maximal energ. of interaction between complementary nucleotides have low streng.hs, the strong.st promoters correspond to promoter clusters characterized by intermediate energ. values.

关键词： DNA sequence Promoter streng.h Nucleotide pair energ. -35 sequence -10 sequence +7 sequence

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Control of Cauchy System for an Elliptic Operator

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Acta Mathematica Sinica,Eng.ish Series 2009年第11期25卷 1819-1834页

作者： g. MASSENg. MOPHOU O. NAKOULIMA Laboratoire de Mathematiques et Informatique Universite des Antilles et de La Guyane Campus Fouillole 97159 Pointe-a-Pitre GUADELOUPE ( FWI)

The control of a Cauchy system for an elliptic operator seems to be g.obally an open problem. In this paper, we analyze this problem using.a reg.larization method which consists in viewing.a sing.lar problem as a limit of a family of well-posed problems. Following.this analysis and assuming.that the interior of considered convex is non-empty, we obtain a sing.lar optimality system （S.O.S.） for the considered control problem.

关键词： optimal control optimality conditions elliptic systems

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