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Investigation of the volatile oils,lipid constituents and biological activity of Ballota andreuzziana,Teucrium zanonii and Verbena tenuisecta in Libya

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Asian Pacific Journal of Tropical Medicine 2010年第8期3卷 594-601页

作者： Khaled A Abdelshafeek Adnan A Elgattar Aziza h Zarkoon Mohamed A Alwahash Abdelaaty A Shahat Al-Tahady University Faculty of ScienceChemistry DepartmentPO 674SirtLibya Phytochemistry Department National Research Centre12311 DokkiCairoEgypt Sebha University Faculty of Science Chemistry DeptartmentSebhaLibya

Objective:To determine the chemical composition of essential oils and lipid constituents of Ballola andreuzziana(***),Teucrium zanonii(***) and Verbena tenuisecta(V. tenuisecta) growing in Libya,and to test the antibacterial activity of different extracts of Teucrium ***:The volatile oils of all plants were extracted by hydrodistillation method and analyzed by GC/MS *** lipid constituents of plants were obtained by extraction with petroleum ether and fractionated into fatty alcohols,fatty acids and unsapoinfiable matters. Antibacterial activity of *** extracts and antioxidant activity of different extracts of T. zanonii were also ***:The volate oil of *** was found to consists of 20 compounds in which caryophyllin is the main one(63.1%),the volatile oil of *** consists of 74 compounds in which germacrene-D was the main compound,while the volatile oil of V. tenuisecta consists of 13 compounds with l-octen-3- ol as a major constituent(52.87%).The study of antimicrobial activity of different extracts of *** showed that,both methanol and butanol extracts exhibited the highest activity against Mycobacterium phlei(***) and Candida albicans(***) respectively,while petroleum ether,fatty alcohols and unsaponifiable fractions had no antimicrobial activity against all the tested microorganisms. Investigation of the antioxidant activity of different extracts of *** using DPPh method proved that,the ethyl acetate and butanol fractions showed the highest activity where the inhibition percentage(1%) are 93.6 and 92.1 ***:This is the first report about the volatile oils of these plants where *** have the highest content and the highest number of the identified *** study of antioxidant *** extracts proved that,the ethyl acetate,butanol and aqueous extracts have the highest antioxidant *** and butanol extracts of *** exhibi

关键词： Ballota andreuzziana Teucrium zanonii Verbena tenuisecta Volatile oil Lipid constituents Biological activity

high temperature oxidation behavior of aluminide on a Ni-based single crystal superalloy in different surface orientations

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Progress in Natural Science:Materials International 2014年第2期24卷 163-170页

作者： Fahamsyah h.Latief Koji Kakehi El-Sayed M.Sherif Department of Mechanical Engineering Tokyo Metropolitan University Center of Excellence for Research in Engineering Materials (CEREM) Advanced Manufacturing Institute King Saud University Electrochemistry and Corrosion Laboratory Department of Physical Chemistry National Research Centre (NRC)

An investigation on oxidation behavior of coated Ni-based single crystal superalloy in different surface orientations has been carried out at1100 ℃. It has been found that the {100} surface shows a better oxidation resistance than the {110} one, which is attributed that the {110}surface had a slightly higher oxidation rate when compared to the {100} surface. The experimental results also indicated that the anisotropic oxidation behavior took place even with a very small difference in the oxidation rates that was found between the two surfaces. The differences of the topologically close packed phase amount and its penetration depth between the two surfaces, including the ratio of α-Al2O3 after 500 h oxidation, were responsible for the oxidation anisotropy.

关键词： Ni-based superalloy Oxidation behavior Microstructure Aluminide coating Crystallographic orientation

Thermal stress analysis method considering geometric effect of risers in sand mold casting process

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China Foundry 2014年第6期11卷 531-536页

作者： S.Y.Kwak h.Y.hwang C.Cho e-Design R&D Group Korea Institute of Industrial Technology (KITECH) Department of Virtual Engineering Korea University of Science and Technology(UST) Department of Mechanical Engineering Inha University

Solidif ication and f luid f low analysis using computer simulation is a current common practice. There is also a high demand for thermal stress analysis in the casting process because casting engineers want to control the defects related to thermal stresses, such as large deformation and crack generation during casting. The riser system is an essential part of preventing the shrinkage defects in the casting process, and it has a great inf luence on thermal phenomena. The analysis domain is dramatically expanded by attaching the riser system to a casting product due to its large volume, and it makes FEM mesh generation diff icult. however, it is diff icult to study and solve the above proposed problem caused by riser system using traditional analysis methods which use single numerical method such as FEM or FDM. In this paper, some research information is presented on the effects of the riser system on thermal stress analysis using a FDM/FEM hybrid method in the casting process simulation. The results show the optimal conditions for stress analysis of the riser model in order to save computation time and memory resources.

关键词： thermal stress sand mold casting riser numerical analysis hybrid method simulation

Lower extremity amputations and long-term outcomes in diabetic foot ulcers:A systematic review

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World Journal of Diabetes 2020年第9期11卷 391-399页

作者： Ayeshmanthe Rathnayake Apoorva Saboo Usman h Malabu henrik Falhammar Department of Medicine Townsville University HospitalTownsville 4814QueenslandAustralia School of Medicine and Dentistry James Cook UniversityTownsville 4811QueenslandAustralia Department of Endocrinology Metabolism and DiabetesKarolinska University HospitalStockholm 17176Sweden Department of Molecular Medicine and Surgery Karolinska InstitutetStockholm 17176Sweden

BACKGROUNDDiabetes mellitus causes a large majority of non-traumatic major and minoramputations globally. Patients with diabetes are clinically complex with amultifactorial association between diabetic foot ulcers (DFU) and subsequentlower extremity amputations (LEA). Few studies show the long-term outcomeswithin the cohort of DFU-associated *** highlight the long-term outcomes of LEA as a result of ***/MEDLINE and Google Scholar were searched for key terms, “diabetes”,“foot ulcers”, “amputations” and “outcomes”. Outcomes such as mortality, reamputation,re-ulceration and functional impact were recorded. Peer-reviewedstudies with adult patients who had DFU, subsequent amputation and follow upof at least 1 year were included. Non-English language articles or studiesinvolving children were *** total of 22 publications with a total of 2334 patients were selected against theinclusion criteria for review. The weighted mean of re-amputation was 20.14%,29.63% and 45.72% at 1, 3 and 5 years respectively. The weighted mean of mortality at 1, 3 and 5 years were 13.62%, 30.25% and 50.55% respectively withsignificantly higher rates associated with major amputation, re-amputation andischemic *** LEA, level of the LEA and patient comorbidities were significant riskfactors contributing to re-ulceration, re-amputation, mortality and depreciatedfunctional status.

关键词： Lower extremity amputations Long-term outcomes Diabetic foot ulcers Quality of life Re-amputation Diabetes

Long-period grating inscription on polymer functionalized optical microfibers and its applications in optical sensing

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Photonics Research 2016年第2期4卷 45-48页

作者： Z.Y.Xu Y.h.Li L.J.Wang Joint Institute for Measurement Science Tsinghua University Shanghai Institute of Laser Plasma State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua University

We demonstrated long-period grating(LPG) inscription on polymer functionalized optical microfibers and its applications in optical sensing. Optical microfibers were functionalized with ultraviolet-sensitive polymethyl methacrylate jackets and, thus, LPGs could be inscribed on optical microfibers via point-by-point ultraviolet laser exposure. For a 2 mm long microfiber LPG(MLPG) inscribed on optical microfibers with a diameter of 5.4 μm, a resonant dip of 15 d B at 1377 nm was observed. This MLPG showed a high sensitivity of strain and axial force, i.e.,-1.93 pm∕με and-1.15 pm∕μN, respectively. Although the intrinsic temperature sensitivity of the LPGs is relatively low, i.e.,-12.75 pm∕°C, it can be increased to be-385.11 pm∕°C by appropriate sealing. Benefiting from the small footprint and high sensitivity, MLPGs could have potential applications in optical sensing of strain,axial force, and temperature.

关键词： MLPG Long-period grating inscription on polymer functionalized optical microfibers and its applications in optical sensing

STUDY ON hOT SAND COOLING EQUIPMENT WITh DAMPING SAND CASCADE AND VERTICAL SPOUTED-FLUIDIZED BED

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Acta Metallurgica Sinica(English Letters) 2005年第5期18卷 669-673页

作者： L. C. Wang F. Wang X.h. You Department of Material Science and Engineering Taiyuan University of Science and Technology Taiyuan 030024 China

A new kind of hot sand cooling equipment with vertical spouted-fluidized bed is developed in this paper. It is similar to the traditional horizontal vibrating fluidized boiling cooler in principle but different from it in structure. The processing principle of the cooler is analyzed. The influence of main structural and processing parameters on the cooling effect and its mechanism are researched. Other characteristics of the cooler are discussed also. Experiment results show that the cooling efficiency η is equal to or larger than 83%, the temperature of output sand is less than 40℃ with the temperature of input sand is about between 80 and 90℃, and the productivity is 5t/ （h·m）

关键词： hot sand cooling fluidized bed foundry equipment

Ultraviolet Radiation Aging of Tafpack-Super Modified Porous Asphalt Concrete

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武汉理工大学学报 2010年第17期32卷 206-209页

作者： hONG W h WU S P XIE J CCCC Second highway Engineering Co.Ltd Xi'an 710000China Key Laboratory of Silicate Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

Ultraviolet aging of porous asphalt concrete is more serious than that of dense-grade concrete,attributing to its relatively high air void structure. And Tafpack-Super (TPS) is widely used as an asphalt viscosifier. For the purpose of determining the effect of TPS content on resistance to ultraviolet aging,TPS powder was added to base asphalt in various weight ratios (0%,4%,8%,12% and 16%). After mixing,the loose mixtures were short-term aged and then put in the Indoor Accelerated Ultraviolet Radiation Aging Oven for several particular times and then were compacted by Gyratory Compactor at 20%±2% air void. The specimens were tested and recorded by means of indirect tensile strength (ITS) to quantify the aging extent. The results show that 8% TPS by weight is the optimum content of base asphalt on resistance to ultraviolet aging. And the ITS of mixtures with different binder reach a peak value for approximately 2 h ultraviolet irradiation.

关键词： tafpack-super ultraviolet radiation ageing indirect tensile strength

Movements and home range of a common species of tree-shrew,Tupaia glis,surrounding houses of otoacariasis cases in Kuantan,Pahang,Malaysia

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Asian Pacific Journal of Tropical Medicine 2010年第6期3卷 427-434页

作者： Mariana A Shukor MN Muhd Norhazizi h Intan Nurlemsha B ho TM Acarology Unit Infectious Diseases Research CentreInstitute for Medical Research50588 Kuala LumpurMalaysia School of Environmental and Natural Resources Sciences Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 BangiSelangorMalaysia

Objective:To document movement patterns,home range,nesting behaviour and social organization of 5 individuals(3 males and 2 females) of a common species of tree-shrew,Tupaia glis(***) surrounding houses of otoacariasis ***:Each shrew was fitted with a transmitter chip radio-collar which operates between the frequencies of 154.13 Mhz to 154.21 *** transmitter was then tracked with a Portable Telemetry Receiver(Sirtrack,New Zealand) fitted with a 3-element Yagi *** shrews were located using standard methods of ground-based *** location was taken from at least 2 directional fixes and a minimum of 3 compass *** were taken hourly for each collared individual from the time of emergence from nest(beginning of activity) till time of entry into the nest(end of activity) every day for 5 to 7 continuous *** series of radio telemetry observations were carried *** bearings,time and positions of an observer were recorded and later plotted on a graph paper in order to derive coordinates of the collared animal.[These coordinates then analyzed using Ecological Software Solutions(Biotas Version 1.03)].Results:Nests were found in a jack fruit tree,long bushes,and 2 *** telemetry detections demonstrated 2 individuals of different sex having nests(or a nest) in the same *** shrews emerged from and returned to their nests between 0601 to 0659 hours and 1901 to 1959 hours,respectively. Both the time of exit from and entry into nest were the same between sexes(P>0.05).Their average total active period was 4.90 to 7.00 hours with a total daily travel distant of 270 m to 382 m.A male and a female shrew can move as far as 3 285 m and 4 591 m,*** movements of *** were during *** regularly entered some houses in the area during day and night except for one individual which visited during daytime *** sizes of home range and core area for the shrews were 2.00-3.40 ha and 0.05-0.4

关键词： Movements home range Tree-shrew Otoacariasis cases Malaysia

Acoustic Supercoupling in a Zero-Compressibility Waveguide

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Research 2019年第1期2019卷 1086-1095页

作者： h.Esfahlani M.S.Byrne M.McDermott A.Alù Photonics Initiative Advanced Science Research CenterCity University of New YorkNew York CityNY 10031USA Department of Electrical and Computer Engineering Te University of Texas at AustinAustinTX 78712USA Electrical Engineering Institute Ecole Polytechnique Fed´erale de Lausanne(EPFL)CH-1015 LausanneSwitzerland Naval Surface Warfare Center Carderock Division West BethesdaMD 20817USA Physics Program Graduate CenterCity University of New YorkNew York CityNY 10026USA Department of Electrical Engineering City College of New YorkNew York CityNY 10031USA

Funneling acoustic waves through largely mismatched channels is of fundamental importance to tailor and transmit sound for a variety of *** electromagnetics,zero-permittivity metamaterials have been used to enhance the coupling of energy in and out of ultranarrow channels,based on a phenomenon known as *** metamaterial channels can support total transmission and complete phase uniformity,independent of the channel length,despite being geometrically mismatched with their input and output *** the feld of acoustics,this phenomenon is challenging to achieve,since it requires zero-density metamaterials,typically realized with waveguides periodically loaded with membranes or *** to electromagnetics,the additional challenge is due to the fact that conventional acoustic waveguides do not support a cut-of for the dominant mode of propagation,and therefore zero-index can be achieved only based on a collective resonance of the loading *** we propose and experimentally realize acoustic supercoupling in a dual regime,using a compressibility-nearzero acoustic *** than engineering the channel with subwavelength inclusions,we operate at the cut-of of a higherorder acoustic mode,demonstrating the realization and efcient excitation of a zero-compressibility waveguide with efective sof *** experimentally verify strong transmission through a largely mismatched channel and uniform phase distribution,independent of the channel *** results open interesting pathways towards the realization of extreme acoustic parameters and their implementation in relevant applications,such as ultrasound imaging,acoustic transduction and sensing,nondestructive evaluation,and sound communications.

关键词： waveguide coupling realization