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Temporal variations of mesozooplankton abundance and biomass in the mangrove creek area along the Karachi coast, Pakistan

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Acta Oceanologica Sinica 2014年第12期33卷 222-230页

作者： Farah Naz Naureen Aziz Qureshi Noor us Saher Centre of Excellence in Marine Biology University of Karachi Department of Zoology Government College University

The temporal variations of mesozooplankton abundance and biomass （1-Volumetric method by settling volume and displacement volume and 2- Gravimetric method through wet weight, dry weight and ash-free dry weight） with relation to environmental parameters were studied in the mangrove creek area of Karachi coast, Pakistan. The data of mesozooplankton samples along with environmental parameters （temperature, salinity, pH, etc.） were collected during January 1998 to December 1998 from two creek stations. The abun-dance of mesozooplankton also exhibited seasonal trends at both stations. At Sta. S2, the highest and low-est abundance values were observed during post-monsoon and southwest monsoon respectively whereas, at Sta. S1, a clear trend of high abundance in pre-monsoon to low abundance in southwest monsoon was observed. Mesozooplankton abundance was also positively correlated with settling volume, displacement volume, wet weight and dry weight. The highest biomass value was observed in the northeast monsoon and pre-monsoon periods. The results of the canonical analysis of the output from the discriminate function was tested. Out of fifteen variables, only one was significantly different in single character ratios dry weight/ash free-dry weight （F3,23=4.78,P＆lt;0.005）. The mesozooplankton community was collectively composed of 28 taxa. Among these groups, copepoda （66.3%）, gastropod larvae （9.94%）, evadne （4.60%）, zoea （3.60%）, cypris nauplii （2.56%）, lemellibranch larvae （1.87%）, chaetognaths （1.81%）, ostracods （1.73%）, lucifer （1.15%） and barnacles nauplii （1.35%） contributed the most to the similarities within Sta. S1, while copepoda （74.68%）, cypris nauplii （5.29%）, gastropods （4.87%）, barnacles nauplii （4.81%）, evadne （1.72%）, zoea （1.53%） and ca-ridean larvae （1.18%） at Sta. S2. The remaining mesozooplanktonic group were accounted for less than 5% and 6% at Sta. S1 and Sta. S2 respectively, of the total organisms. Similarity percentage （SIMPER） analysis revealed t

关键词： mesozooplankton abundance biomass Karachi Pakistan

Activity and Stability of Rare Earth-Based Hydride Alloys as Catalysts of Hydrogen Absorption-Oxidation Reactions

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Journal of Rare Earths 2004年第6期22卷 871-874页

作者：应桃开高学平胡伟康 Noréus Dag College of Biology and Chemistry Zhejiang Normal University Jinhua 321004China Institute of New Energy Material Chemistry Nankai University Tianjin 300071China Department of Structural Chemistry Arrhenius Laboratory Stockholm University S-106 91 Stockholm Sweden

Rare earth-based AB(5)-type hydrogen storage alloys as catalysts of hydrogen-diffusion electrodes for hydrogen absorption and oxidation reactions in alkaline fuel cells were investigated. It is demonstrated that the metahydride hydrogen-diffusion electrodes could be charged by hydrogen gas and electrochemically discharged, at the same time to retain a stable oxidation potential for a long period. The catalytic activities and stability are almost comparable with a Pt catalyst on the active carbon. Further improvement of performances is expected via reduction of catalyst size into nanometers.

关键词： inorganic chemistry electrocatalyst alkaline fuel cell hydrogen oxidation rare earths

Interferometric orbit determination for geostationary satellites

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Science China(Information Sciences) 2017年第6期60卷 22-32页

作者： Roger M.FusTER Marc FERNNDEZ usóN Antoni BROQUETAS IBARS Remote Sensing Laboratory Department of Signal and Communications TheoryUniversitat Politècnica de Catalunya

Future Geo SAR missions are expected to provide higher resolution radar images featuring shorter revisit times by locating a radar payload on-board of a geostationary satellite. One of the main challenges in Geo SAR processing is accurately determining the satellite orbit to obtain a precise phase history, in order to properly focus the retrieved data. To tackle this challenge, a multiple baseline ground-based interferometer is proposed as a compact and reliable method to achieve an unprecedented accuracy. As a proof of concept, this paper presents the results obtained from a single baseline prototype, whose results can be extrapolated to a larger system, able to be used in future missions.

关键词： GeoSAR interferometry orbit determination geostationary SAR

Comparative Study on Various Strength Parameters of Structural Elements Made from Cross-Laminated Timber

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Journal of Renewable Materials 2022年第6期10卷 1575-1606页

作者： Mohammad Anwar-us-Saadat Janeshka Goonewardena Bidur Kafle Mahmud Ashraf Mahbube Subhani School of Engineering Technology-Civil Melbourne PolytechnicEpping3076Australia School of Engineering Deakin UniversityWaurn Ponds3216Australia

Cross laminated timber(CLT)is an innovative and environment friendly engineered timber product with superior structural *** offers strong resistance against both in-plane and out-of-plane ***,it is widely used as floors,roofs or wall *** experimental research on CLT under various loading conditions has been done in the recent *** article presents a comprehensive review of various design methods to determine basic mechanical properties such as tension,compression and rolling shear strength of CLT with primary focus on Norway *** relevant experimental data available from existing literature were collated and consequently been used to evaluate the performance of various methods to design CLT *** comparison revealed that different methods show considerable variance in predicting the capacity of CLT panels due to the variation in timber species,which affects the corresponding mechanical properties of the *** addition to species,rolling shear properties can also vary considerably depending on the type of experimental technique used for testing.A predictive model has also been proposed to correlate rolling shear strength obtained from shear analogy method to that obtained using planar shear.

关键词： Cross-laminated timber mass timber mechanical strength rolling shear strength planar shear test short span bending test

A modified isooctane-based DNA extraction method from crude oil

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mLife 2023年第3期2卷 328-338页

作者： Armando Alibrandi Rolando Primio Alexander Bartholomäus Jens Kallmeyer GFZ German Research Centre for Geoscience Section GeomicrobiologyPotsdamGermany Aker BP LysakerNorway

Microbes from oil reservoirs shape petroleum composition through processes such as biodegradation or *** processes are considered economically detrimental and might pose health and safety *** is therefore crucial to understand the composition of a reservoir's microbial community and its metabolic ***,such analyses are hindered by difficulties in extracting DNA from such complex fluids as crude ***,we present a novel DNA extraction method from oils with a wide American Petroleum Institute(API)gravity(density)*** investigated the ability to extract cells from oils with different solvents and surfactants,the latter both nonionic and ***,we evaluated three DNA extraction ***,the best DNA yields and the highest number of 16S rRNA reads were achieved with isooctane as a solvent,followed by an ionic surfactant treatment using sodium dodecyl sulfate and DNA extraction using the PowerSoil Pro Kit(Qiagen).The final method was then applied to various oils from oil reservoirs collected in aseptic *** the expected low cell density of 10^(1)–10^(3)cells/ml,the new method yielded reliable results,with average 16S rRNA sequencing reads in the order of 41431(±8860)per ***,halophilic,and anaerobic taxa,which are most likely to be indigenous to the oil reservoir,were found in all *** gravity and DNA yield,despite the sufficient DNA obtained,did not show a correlation.

关键词： crude oil DNA extraction method oil reservoir microbiome

Novel nanocomposites based on a strawberry-like gold-coated magnetite （Fe@Au） for protein separation in multiple myeloma serum samples

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Nano Research 2015年第4期8卷 1189-1198页

作者： Jose E. Araujo Carlos Lodeiro Jose L. Capelo Benito Rodrfguez-Gonzalez Alcindo A. dos Santos~ Hugo M. Santos Javier ferna.ndez-Lodeiro BIOSCOPE Research Group UCIBIO-REQUIMTE Department of Chemistry Faculty of Science and Technology University NOVA of Lisbon 2829-516 Caparica Portugal PROTEOMASS Scientific Society Madan Parque Rua dos Inventores 2825-182 Caparica Portuga Scientific and Technological Research Assistance Centre (CACTI) University of Vigo Vigo Spain Instituto de Quimica Universidade de Sao Paulo Av. Prof. Lineu Prestes 748 CxP 26077 Sao Paulo 05508-000 Brazil

A new process to produce magnetite partially coated with strawberry-like gold nanoparticles in aqueous media is reported. The fast response to magnetic fields and optical properties of gold nanoparticle-based colloidal systems are the two main advantages of this new Fe@Au nanomaterial. These advantages allow for the use of this new colloidal nanomaterial for various purposes in proteomics and biomedicine, as proteins can bind to the surface, and the surface can also be funcfionalized. As proof-of-concept, the new Fe@Au nanoparticles have been assessed in biomarker discovery as a tool for pre-concentration and separation of proteins from complex proteomes. To this end, sera from healthy people were compared with sera from patients diagnosed with multiple myeloma. The application of this new Fe@Au nanomaterial combined with mass spectrometry has allowed for the identification of 53 proteins, and it has also shown that the heat shock protein HSP75 and the plasma protease C1 inhibitor are potential biomarkers for diagnostics and control of multilvle mveloma vro^ression.

关键词： nanoproteomics strawberry-nanopartides multifunctional hybridnanoparticles biomarkers multiple myeloma

Participatory Mapping and Visualization of Local Knowledge:An Example from Eberbach, Germany

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International Journal of Disaster Risk Science 2021年第1期12卷 56-71页

作者： Carolin Klonner Tomás J.usón Nicole Aeschbach Bernhard Höfle Institute of Geography Heidelberg University69120 HeidelbergGermany Institute of European Ethnology and IRI THESys(Integrative Research Institute on Transformations of Human-Environment Systems) Humboldt University of Berlin10117 BerlinGermany

A rise in the number of flood-affected people and areas has increased the interest in new methods and concepts that account for this *** are integrated into disaster risk reduction processes through participatory approaches and can provide valuable up-to-date local *** a field study in Eberbach(Baden–Wuerttemberg,Germany)sketch maps and questionnaires were used to capture local knowledge about *** on a previous study on urban flooding in Santiago de Chile,the tools were adapted and applied to river flooding in the city of Eberbach,which is regularly flooded by the Neckar River,a major river in southwest *** empirical database of the study comprises 40 participants in the study area and 40 in a control *** of the participants in each group are residents and half are *** sampling was used,and the questionnaires aimed to gather demographic information and explore what factors,such as property,influence the risk perception of the study *** results show that residents identify a larger spatial area as at risk than pedestrians,and owning property leads to higher risk *** flood type influenced the choice of the base maps for the sketch *** river flooding,one map with an overview of the area was sufficient,while for urban flooding a second map with more details of the area also enables the marking of small *** information gathered can complement authoritative data such as from flood *** participatory approach also increases the communication and trust between local governments,researchers,and citizens.

关键词： Disaster risk reduction Flooding Local knowledge Participatory approach Sketch maps Volunteered geographic information

A New Model Inspired by the Pompeii Worm to Reverse Overheating in Nanosatellites

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Space(Science & Technology) 2023年第1期3卷 133-140页

作者： Ayşe MeriçYazıcı erik Persson Department of Philosophy Lund UniversityLundSweden

Nanosatellites are exposed to extreme temperatures on the spacecraft surface,which can reach up to±100℃.In this paper,we suggest a novel solution to this challenge by the use of *** imitation of the behavior of living creatures in nature is an attempt to understand and synthesize a natural object or phenomenon in an abstract or concrete *** inspiration from living things in nature can come through the materials,processes,or designs we see around us,and there is no engineering effort *** nature,the best example of temperature reversal is the Pompeii *** Pompeii worm realizes the conversion of the excess heat it is exposed to into cooling inside a multilayered *** this work,inspired by the strategy of the Pompeii worm in reversing overheating,we present a new model for the overheating problem in nanosatellites.

关键词： form heating extreme

Measuring the mechanical properties of small body regolith layers using a granular penetrometer

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Astrodynamics 2023年第1期7卷 15-29页

作者： Bin Cheng erik Asphaug Yang Yu Hexi Baoyin School of Aerospace Engineering Tsinghua UniversityBeijing 100084China Lunar&Planetary Laboratory University of ArizonaTucsonAZ 85721USA School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

Small bodies in the solar system are known to be covered by a layer of loose unconsolidated soil composed of grains ranging from dusty sands to rugged *** geophysical processes have modified these regolith layers since their ***,the landforms on regolith-blanketed surfaces hold vital clues for reconstructing the geological processes occurring on small ***,the mechanical strength of small body regolith remains unclear,which is an important parameter for understanding its dynamic ***,regolith mechanical properties are key factors for the design and operation of space missions that interact with small body *** granular penetrometer,which is an instrument that facilitates in situ mechanical characterization of surface/subsurface materials,has attracted significant ***,we still do not fully understand the penetration dynamics related to granular regolith,partially because of the experimental difficulties in measuring grain-scale responses under microgravity,particularly on the longer timescales of small body *** this study,we analyzed the slow intrusion ofa locomotor into granular matter through large-scale numerical simulations based on a soft sphere discrete element *** demonstrated that the resistance force of cohesionlessregolith increases abruptly with penetration depth after contact and then transitions to a linear *** scale factor of the steady-state component is roughly proportionalto the internal friction of the granular materials,which allows us to deduce the shearstrength of planetary soils by measuring their force depth *** cohesion is included,due to the brittle behavior of cohesive materials,the resistance profile is characterized by a stationary state at a large penetration *** saturation resistance,which represents the failure threshold of granular materials,increases with the cohesion strength of the *** positive correlation pr

关键词： small body regolith granular penetrometer small body exploration granular dynamics