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Advances in Polar Science 2014年第2期25卷 92-96页

作者： Daniela N. Correa-Llantén maximiliano j. amenábar Patricio A. Mu?oz María T. Monsalves Miguel E. Castro j.nny M. Blamey Fundación Científicay Cultural Biociencia José Domingo Ca?as 2280 Santiago 8340457 Chile

A gram-positive, rod-shaped, aerobic, thermo-acidophilic bacterium CC2 （optimal temperature 55℃ and pH 4.0）, belonging to the genus Alicyclobacillus was isolated from geothermal soil collected from ＂Cerro Caliente＂, Deception Island, Antarctica. Owing to the harsh environmental conditions found in this territory, microorganisms are exposed to conditions that trigger the generation of reactive oxygen species （ROS）. They must have an effective antioxidant defense system to deal with this oxidative stress. We focused on one of the most important enzymes： superoxide dismutase, which was partially purified and characterized. This study presents the first report of a thermo-acidophilic bacterium isolated from Deception lsland with a thermostable superoxide dismutase （SOD）.

关键词： Antarctica thermo-acidophile SOD geothermal Deception Island

Surface engineering with ionic polymers on membranes for boron removal

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 61-69页

作者： Xiting Zhang Chenyi Fang j.Paul Chen Sui Zhang Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117576Singapore Department of Civil and Environmental Engineering National University of SingaporeSingapore 119260Singapore College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Removal of boric acid from seawater and wastewater using reverse osmosis membrane technologies is imperative and yet remains inadequately addressed by current commercial *** research efforts performed post-modification of reverse osmosis membranes to enhance boron rej.ction,which is usually accompanied by substantial sacrifice in water *** study delves into the surface engineering of low-pressure reverse osmosis membranes,aiming to elevate boron removal efficiency while maintaining optimal salt rej.ction and water *** were modified by the self-polymerization and co-deposition of dopamine and polystyrene sulfonate at varying ratios and *** surfaces became smoother and more hydrophilic after *** optimum membrane exhibited a water permeability of 9.2±0.1 L·m^(-2)·h^(-1)·bar^(-1),NaCl rej.ction of 95.8%±0.3%,and boron rej.ction of 49.7%±0.1% and 99.6%±0.3% at neutral and alkaline pH,*** water permeability is reduced by less than 15%,while the boron rej.ction is 3.7 times higher compared to the blank *** research provides a promising avenue for enhancing boron removal in reverse osmosis membranes and addressing water quality concerns in the desalination process.

关键词： membrane low-pressure reverse osmosis boron surface engineering

Single-atom Pt on carbon nanotubes for selective electrocatalysis

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Carbon Energy 2024年第1期6卷 63-71页

作者： Samuel S.Hardisty Xiaoqian Lin Anthony R.j.Kucernak David Zitoun Department of Chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael Department of Chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOR).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(SWCNTs)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOR activity than state-of-the-art 30%Pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOR arose as the main fingerprint of the catalyst confinement in the SWCNTs.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts

Developing an Evolutionary Algorithm to Search for an Optimal Multi-Mother Wavelet Packets Combination

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j.urnal of Biomedical Science and Engineering 2015年第7期8卷 458-470页

作者： Ohad bar Siman Tov j. David Schaffer Kenneth j. McLeod Department of Electrical and Computer Engineering State University of New York at Binghamton Binghamton NY USA Department of Bioengineering State University of New York at Binghamton Binghamton NY USA

The wavelet transform is a popular analysis tool for non-stationary data, but in many cases, the choice of the mother wavelet and basis set remains uncertain, particularly when dealing with physiological data. Furthermore, the possibility exists for combining information from numerous mother wavelets so as to exploit different features from the data. However, the combinatorics become daunting given the large number of basis sets that can be utilized. Recent work in evolutionary computation has produced a subset selection genetic algorithm specifically aimed at the discovery of small, high-performance, subsets from among a large pool of candidates. Our aim was to apply this algorithm to the task of locating subsets of packets from multiple mother wavelet decompositions to estimate cardiac output from chest wall motions while avoiding the computational cost of full signal reconstruction. We present experiments which show how a continuous assessment metric can be extracted from the wavelets coefficients, but the dual-obj.ctive nature of the algorithm (high accuracy with small feature sets) imposes a need to restrict the sensitivity of the continuous accuracy metric in order to achieve the small subset size desired. A possibly subtle tradeoff seems to be needed to meet the dual obj.ctives.

关键词： Wavelet Transform Data Mining Genetic Algorithm

Strengthening an in-service reinforcement concrete bridge with prestressed CFRP bars

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j.urnal of Zhej.ang University-Science A(Applied Physics & Engineering) 2009年第5期10卷 635-644页

作者： Hai-long WANG Wei-liang j.N David j. CLELAND Ai-hui ZHANG Department of Civil Engineering Zhejiang University Hangzhou 310027 China School of Planning Architecture and Civil Engineering Queen's University Belfast Belfast BT9 5AG UK

Carbon fiber reinforced polymer (CFRP) bars were prestressed for the structural strengthening of 8 T-shaped rein-forced concrete (RC) beams of a 21-year-old bridge in China. The ultimate bearing capacity of the existing bridge after retrofit was discussed on the basis of concrete structures theory. The flexural strengths of RC beams strengthened with CFRP bars were controlled by the failure of concrete in compression and a prestressing method was applied in the retrofit. The field construction processes of strengthening with CFRP bars-including grouting cracks, cutting groove, grouting epoxy and embedding CFRP bars, surface treating, banding with the U-type CFRP sheets, releasing external prestressed steel tendons-were introduced in detail. In order to evaluate the effectiveness of this strengthening method, field tests using vehicles as live load were applied before and after the retrofit. The test results of deflection and concrete strain of the T-shaped beams with and without strengthening show that the capacity of the repaired bridge, including the bending strength and stiffness, is enhanced. The measurements of crack width also indicate that this strengthening method can enhance the durability of bridges. Therefore, the proposed strengthening technology is feasible and effective.

关键词： Carbon fiber reinforced polymer (CFRP) bar Reinforced concrete (RC) bridge Strengthening Construction pro-cedure Field test T-shaped beam

Determination of fractional energy loss of waves in nearshore waters using an improved high-order Boussinesq-type model

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Chinese j.urnal of Oceanology and Limnology 2009年第3期27卷 621-629页

作者：何海伦宋金宝 Patrick j. Lynett 李爽 Institute of Oceanology Chinese Academy of Sciences Key Laboratory of Ocean Circulation and Waves(KLOCAW) Chinese Academy of Sciences Graduate School Chinese Academy of Sciences Department of Civil Engineering Texas A&M University

Fractional energy losses of waves due to wave breaking when passing over a submerged bar are studied systematically using a modified numerical code that is based on the high-order Boussinesq-type *** model is first tested by the additional experimental data,and the model's capability of simulating the wave transformation over both gentle slope and steep slope is ***,the model's breaking index is replaced and *** new breaking index,which is optimized from the several breaking indices,is not sensitive to the spatial grid length and includes the bottom *** tests show that the modified model with the new breaking index is more stable and efficient for the shallow-water wave ***,the modified model is used to study the fractional energy losses for the regular waves propagating and breaking over a submerged *** results have revealed that how the nonlinearity and the dispersion of the incident waves as well as the dimensionless bar height(normalized by water depth) dominate the fractional energy *** is also found that the bar slope(limited to gentle slopes that less than 1:10) and the dimensionless bar length(normalized by incident wave length) have negligible effects on the fractional energy losses.

关键词： breaking waves Boussinesq-type equations nearshore wave modeling fractional energy loss

Advent of clean and green technology for preparation of low-cholesterol dairy cream powder:supercritical fluid extraction process

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Food Quality and Safety 2018年第4期2卷 205-211页

作者： Mousumi Ghosh Chitra j. Shubhangi Srivastava Hari Niwas Mishra Agricultural and Food Engineering Department Indian Institute of Technology KharagpurNalanda roadKharagpurWest Mednipore721302India

Obj.ctives:Due to health issues related to cholesterol and the emphasis on manufacture of low cholesterol food products,the research was undertaken for the extraction of cholesterol from cream powder using supercritical fluid extraction(SCFE)*** and Methods:Face centered composite design(FCCD)was used to design the experiments with three independent variables viz.,extraction temperature(40˚C-75˚C),extraction pressure(100-250 bar)and dynamic time(2.5-3.5 h)taking two responses(cholesterol and fat content).The standardized flow rate and static time were 5 L/min(expanded CO_(2) gas)and 30 min,*** surface methodology was used for optimizing the process ***:It was found that higher operating pressure,low extraction temperature and moderate amount of dynamic time facilitated the removal of *** optimized process conditions of 75˚C,204 bar and 3.5 h dynamic time yielded 39%reduction in cholesterol content and 10.6%reduction in total fat content of the cream ***:Thus,a low cholesterol cream powder was developed with health benefits for people suffering from cardiovascular diseases.

关键词： cholesterol supercritical fluid extraction HPLC face-centred composite design response surface methodology

Unusual Presentation of Endometrial Cancer: A Clinicopathological Study of One Case

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Open j.urnal of Obstetrics and Gynecology 2015年第1期5卷 23-27页

作者： j. Munné F. Alameda A. Bergueiro G. Mancebo L. Garrigós T. baró B. Lloveras j. Gimeno R. Carreras S. Serrano Department of Pathology Hospital del Mar Barcelona Spain Universitat Autonoma de barcelona Barcelona Spain Department of Obstetrics and Gynecology Hospital del Mar Barcelona Spain Department of Oncology Hospital del Mar Barcelona Spain

Endometrial carcinoma is the most frequent genital tract malignancy. The first symptom (guide-symptom) is usually metrorrhagia;however, in around 10% of cases it is not. In contrast, osseous metastases are infrequent in endometrial cancer. The bones of the pelvis and lower extremities are those most frequently involved in disseminated metastatic diseases. In these cases, endometrial cancer is usually high grade (Grade III). Case report: 56-year-old woman who presented right inguinal pain. The X-ray showed a lithic lesion in the right ischium. A histopathological study demonstrated a metastatic lesion, suspected to be endometrial cancer. The computer tomography scan revealed a uterine mass and a second lithic lesion in the right tibia. The patient received chemotherapy (carboplatin and paclitaxel), and the bone lesions were irradiated. The patient is still alive 18 months after the diagnosis. This case emphasizes the importance of considering an endometrial primary tumor when evaluating bone metastasis of unknown primary cancer.

关键词： Osseous Metastasis Endometrial Carcinoma Immunohistochemistry

The effect of carbon nanotubes and polypropylene fibers on bond of reinforcing bars in strain resilient cementitious composites

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Frontiers of Structural and Civil Engineering 2016年第2期10卷 214-223页

作者： Souzana P. TASTANI Maria S. KONSTA-GDOUTOS, Stavroula j. PANTAZOPOULOU Victor BALOPOULOS Department of Civil Engineering Democritus University oJ Thrace Vas. Sofias Street #12 Xanthi 67100 Greece

Stress transfer between reinforcing bars and concrete is engaged through rib translation relative to concrete, and comprises longitudinal bond stresses and radial pressure. The radial pressure is equilibrated by hoop tension undertaken by the concrete cover. Owing to concrete＇s poor tensile properties in terms of strength and deformability, the equilibrium is instantly released upon radial cracking of the cover along the anchorage with commensurate abrupt loss of the bond strength. Any improvement of the matrix tensile properties is expected to favorably affect bond in terms of strength, resilience to pullout slip, residual resistance and controlled *** aim of this paper is to investigate the local bond of steel bars developed in adverse tensile stress conditions in the concrete cover. In the tests, the matrix comprises a novel, strain resilient cementitious composite （SRCC） reinforced with polypropylene fibers （PP） with the synergistic action of carbon nano-tubes （CNT）. Local bond is developed over a short anchorage length occurring in the constant moment region of a four-point bending short beam. Parameters of investigation were the material structure （comprising a basic control mix, reinforced with CNTs and/or PP fibers） and the age of testing. Accompanying tests used to characterize the cementitious material were also conducted. The test results illustrate that all the benefits gained due to the synergy between PP fibers and CNTs in the matrix, namely the maintenance of the multi-cracking effect with time, the increased strength and deformability as well as the highly increased material toughness, were imparted in the recorded bond response. The local bond response curves thus obtained were marked by a resilient appearance exhibiting sustained strength up to large levels of controlled bar-slip; the elasto-plastic bond response envelope was a result of the confining synergistic effect of CNTs and the PP fibers, and it occurred even without bar yielding.

关键词： carbon nanotubes strain resilient cementitious composite polypropylene fibers tensile bending bond

An underlying geometrical manifold for Hamiltonian mechanics

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Frontiers of physics 2017年第1期12卷 123-131页

作者： L. P. Horwitz A. Yahalom j. Levitan M. Lewkowicz School of Physics Tel Aviv University Ramat Aviv 69978 Israel Department of Physics Bar llan University Ramat Gan 52900 Israel Department of Physics Ariel University Ariel 40700 Israel Department of Electrical and Electronic Engineering Ariel University Ariel 40700 Israel

We show that there exists an underlying manifold with a conformal metric and compatible connection form, and a metric type Hamiltonian （which we call the geometrical picture）, that can be put into correspondence with the usual Hamilton-Lagrange mechanics. The requirement of dynamical equiva- lence of the two types of Hamiltonians, that the momenta generated by the two pictures be equal for all times, is sufficient to determine an expansion of the conformal factor, defined on the geometrical coordinate representation, in its domain of analyticity with coefficients to all orders determined by functions of the potential of the Hamiltonian-Lagrange picture, defined on the Hamilton-Lagrange coordinate representation, and its derivatives. Conversely, if the conformal function is known, the potential of a Hamilton-Lagrange picture can be determined in a similar way. We show that arbi- trary local variations of the orbits in the Hamilton-Lagrange picture can be generated by variations along geodesics in the geometrical picture and establish a correspondence which provides a basis for understanding how the instability in the geometrical picture is manifested in the instability of the the original Hamiltonian motion.

关键词： geometrical Hamiltonian stability analysis coordinate mapping Riemann-Euclidean Hamiltonian equivalence