检索结果-南通市图书馆

Microstructure of Si Cones Prepared by ar^+-Sputtering Si/Mo Target

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2002年第2期18卷 173-175页

作者： X.L.Ma n.G.Shang 等 ShenyangnationalLaboratoryforMaterialsScience InstituteofMetalResearchChineseAcademyofSciencesShenyang110016China CenterofSuper-DiamondandAdvancedFilms&DepartmentofPhysicsand

By ar+ sputtering onto Si wafers which were surrounded by Mo plates, uniform cones over a large area on the Si surface were formed. Scanning electron microscopic study showed that the cones were formed on the entire surface of the Si wafer. The dimensions of the uniform cones were one micrometer in diameter and 5-6 micrometers high. They were further characterized by means of cross-sectional transmission electron microscopy, with the technique of micro-diffractions. It was found that the cone contained a pure Si regime and a Mo-rich regime. In the binary Mo-Si zone, we identified three distinct areas vertically: (1) domains of Mo-induced Si ordered structures, (2) a small volume of a new Mo3Si2 structural variant, intergrown with the Si ordered structure, and (3) a small amount of pure Mo nanoparticles covering the surface of the cones. The formation of the large and uniform cones may provide a new surface configuration for potential applications in surface science and technology.

关键词： Si cones Ordered structure Mo silicide

Adenosine 5'triphosphate transport and accumulation during the cold preservation of rat hepatocytes in University of Wisconsin solution

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2005年第13期11卷 1957-1964页

作者： María E.Mamprin Félix Vega Joaquín V.Rodriguez Farmacología

AIM: We used isolated hepatocytes to investigate how different concentrations of ATP in the University of Wisconsin (UW) solution affected both cellular ATP content and cell viability during the cold storage and the rewarming step. The mechanism involved in ATP transport and accumulation in hypothermia was also determined. METHODS: The cells were preserved up to 72 h in different conditions: UW solution without ATP (a-group), UW+5 mmol/L ATP (b-group), and UW+10 mmol/L ATP (c-group). The ATP content and the cell viability (LDH release) were determined during the cold storage and the rewarming step. In the groups a and c, the respiratory function of the cells at rewarming was studied. In addition, the cell volume of hepatocytes and the mechanism involved in ATP transport and accumulation were assessed. The extracellular degradation of exogenous nucleotides during transport experiments was investigated by a HPLC technique. RESULTS: After three days of cold storage a loss of cellular ATP content was observed in hepatocytes preserved either without nucleotides (a-group) or with 5 mmol/L ATP (b-group). In contrast, 10 mmol/L ATP (c-group) was able to maintain a normal ATP cellular content, with only a 6% diminution after 72 h of cold storage. The respiratory function was significantly different in hepatocytes preserved with 10 mmol/L ATP than without ATP. no significant change was detected For the three groups in cellular volume during the cold storage. We also report that the time course accumulation of [3H]-ATP by cold stored hepatocytes is a rapid process that is completed after 180 s with linear dependence on the extracellular ATP concentration (linear fitting results in a slope of 0.5624±0.1179 mmol/L ATP intracell/mmcl/L ATP extracell). COnCLUSIOn: Our results show that, during hypothermic storage in UW solution, hepatocytes are permeable to ATP by a diffusive mechanism. Also, we found that it is ATP the main extracellular nucleotide available for transport and it

关键词： UW ATP Hepatocytes Cold preservation Hypothermia Oxygen

Fragile X Messenger Ribonucleoprotein 1(FMR1), a novel inhibitor of osteoblast/osteocyte differentiation, regulates bone formation, mass, and strength in young and aged male and female mice

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Bone Research 2023年第2期11卷 384-397页

作者： Padmini Deosthale Julián Balanta-Melo Amy Creecy Chongshan Liu Alejandro Marcial Laura Morales Julita Cridlin Sylvia Robertson Chiebuka Okpara David J.Sanchez Mahdi Ayoubi Joaquín n.Lugo Christopher J.Hernandez Joseph M.Wallace Lilian I.Plotkin Department of Anatomy Cell Biology&PhysiologyIndiana University School of MedicineIndianapolisIN46202USA Roudebush Veterans Administration Medical Center IndianapolisIN46202USA Indiana Center for Musculoskeletal Health IndianapolisIN46202USA Universidad del Valle School of Dentistry Cali 760043Colombia Department of Biomedical Engineering Indiana University-Purdue University Indianapolis46202 IndianapolisIN46202USA Sibley School of Mechanical and Aerospace Engineering Cornell UniversityIthacaNY 14853USA Department of Materials Science and Engineering Cornell UniversityIthacaNY14853USA Department of Psychology and neuroscience Baylor UniversityWacoTX76798USA

Fragile X Messenger Ribonucleoprotein 1(FMR1)gene mutations lead to fragile X syndrome,cognitive disorders,and,in some individuals,scoliosis and craniofacial ***-month-old(mo)male mice with deletion of the FMR1 gene exhibit a mild increase in cortical and cancellous femoral bone ***,consequences of absence of FMR1 in bone of young/aged male/female mice and the cellular basis of the skeletal phenotype remain *** found that absence of FMR1 results in improved bone properties with higher bone mineral density in both sexes and in 2-and 9-mo *** cancellous bone mass is higher only in females,whereas,cortical bone mass is higher in 2-and 9-mo males,but higher in 2-and lower in 9-mo female FMR1-knockout ***,male bones show higher biomechanical properties at 2mo,and females at both *** of FMR1 increases osteoblast/mineralization/bone formation and osteocyte dendricity/gene expression in vivo/ex vivo/in vitro,without affecting osteoclasts in vivo/ex ***,FMR1 is a novel osteoblast/osteocyte differentiation inhibitor,and its absence leads to age-,site-and sex-dependent higher bone mass/strength.

关键词： female Messenger agile

Hepatitis B virus subgenotypes and basal core promoter mutations in Indonesia

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2009年第32期15卷 4028-4036页

作者： Andi Utama Sigit Purwantomo Marlinang Diarta Siburian Rama Dhenni Rino Alvani Gani Irsan Hasan Andri Sanityoso Upik Anderiani Miskad Fardah Akil Irawan Yusuf Wenny Astuti Achwan Soewignjo Soemohardjo Syafruddin ar Lelosutan Ruswhandi Martamala Benyamin Lukito Unggul Budihusodo Laurentius Adrianus Lesmana Ali Sulaiman Susan Tai Molecular Epidemiology Division Mochtar Riady Institute for NanotechnologyLippo KarawaciTangerangBanten 15810Indonesia Hepatology Division Department of Internal MedicineFaculty of MedicineUniversity of IndonesiaJakarta 10430Indonesia Center of Gastroentero-Hepatology Department of Internal MedicineFaculty of MedicineHasanuddin UniversityMakassar 90245Indonesia Department of Internal Medicine Mataram General HospitalMataram 83127Indonesia Gastroentero-Hepatology Division Department of Internal MedicineGatot Soebroto HospitalJakarta 10410Indonesia Department of Internal Medicine Siloam Hospital Lippo KarawaciTangerang Banten 15810Indonesia

AIM： To identify the distribution of hepatitis B virus （HBV） subgenotype and basal core promoter （BCP） mutations among patients with HBV-associated liver disease in Indonesia.METHODS： Patients with chronic hepatitis （CH, n =61）, liver cirrhosis （LC, n = 62）, and hepatocellular carcinoma （HCC, n = 48） were included in this study. HBV subgenotype was identified based on S or preS gene sequence, and mutations in the HBx gene including the overlapping BCP region were examined by direct sequencing.RESULTS： HBV genotype B （subgenotypes B2, B3, B4, 85 and B7） the major genotype in the samples, accounted for 75.4%, 71.0% and 75.0% of CH, LC and HCC patients, respectively, while the genotype C （subgenotypes C1, C2 and C3） was detected in 24.6%, 29.0%, and 25.0% of CH, LC, and HCC patients, respectively. Subgenotypes B3 （84.9%） and C1 （82.2%） were the main subgenotype in HBV genotype B and C, respectively. Serotype adw2 （84.9%） and adrq＋（89.4%） were the most prevalent in HBV genotype B and C, respectively. Double mutation （A1762T/G1764A） in the BCP was significantly higher in LC （59.7%） and HCC （54.2%） than in CH （19.7%）, suggesting that this mutation was associated with severity of liver disease. The T1753V was also higher in LC （46.8%）, but lower in HCC （22.9%） and CH （18.0%）, suggesting that this mutation may be an indicator of cirrhosis.COnCLUSIOn： HBV genotype B/B3 and C/C1 are the major genotypes in Indonesia. Mutations in BCP, such as A1762T/G1764A and T1753V, might have an association with manifestations of liver disease.

关键词： Basal core promoter mutation Hepatitis Bvirus Indonesia Liver disease Subgenotype

ar-assisted robot welding programming

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Manufacturing 2020年第1期8卷 40-48页

作者： S.K.Ong A.Y.C.nee A.W.W.Yew n.K.Thanigaivel Department of Mechanical Engineering Faculty of EngineeringNational University of SingaporeSingapore

Robotic welding demands high accuracy and ***,robot programming is often a tedious and time-consuming process that requires expert *** paper presents an augmented reality assisted robot welding task programming(arWP)system using a user-friendly augmented reality(ar)interface that simplifies and speeds up the programming of robotic welding *** arWP system makes the programming of robot welding tasks more user-friendly and reduces the need for trained programmers and expertise in specific robotic *** ar interface simplifies the definition of a welding path as well as the welding gun orientation,and the system;the system can locate the welding seam of a workpiece quickly and generate a viable welding path based on the user *** developed system is integrated with the touch-sensing capability of welding robots in order to locate the welding path accurately based on the user input,for fillet *** system is applicable to other welding processes and methods of seam *** system implementation is described and evaluated with a case study.

关键词： Augmented reality(ar) Robot programming Welding Seam tracking

Isotopic Ages of the Penglai Group in the Jiaobei Belt and Their Geotectonic Implications

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 1994年第4期68卷 417-433页

作者： W.R.Fitches C.J.n.Fletcher Institute of Earth Studies University College of WalesAberystwythSY23 3D B U KBritish Geological SurveyAberystwythSY 23 4BYU K

The Penglai Group in the Jiaobei Belt is the only remaining cover of the archaean to Early Proterozoic crystalline basement in eastern Shandong. The ages of deposition of the Penglai Group and of its deformation and metamorphism have long been a subject of speculation. Whole-rock Rb-Sr ages, illite-whole-rock pair Rb-Sr ages and illite K-ar ages recently obtained from the Penglai Group slates are reported and interpreted in this paper. On the basis of structural and metamorphic studies coupled with analyses of illite crystallinity, XRD and SEM , a whole-rock age of 473±32 Ma (Ordovician) is interpreted as the time of termination of burial metamorphism experienced by the Penglai Group. Therefore, the age of the Penghai Group is older than Ordovician. The first-phase folding and syntectonic low greenschist facies metamorphism in the Penglai Group, i.e. the Penglai Movement, took place before 299±4 Ma B.P., i.e in the Late Carboniferous. The Penglai Movement that occurred in the Jiaobei Belt on the southern margin of the north China Plate is attributed to collision between the north China and Yangtze plates along the Jiaonan Collision Belt. This demonstrates that the continent-continent collision between the north China and Yangtze plates east of the Tan-Lu Fault Zone took place in the Late Carboniferous. The collision caused n-S compression and deformation in the southern margin belt of the north China Plate north of the Qinling-Dabieshan-Jiaonan Collision Belt.

关键词： illite age Jiaobei Belt north China Plate Yangtze Plate plate collision

Effect of nd^(3+) substitution on structural and magnetic properties of Mg-Cd ferrites synthesized by microwave sintering technique

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2018年第4期36卷 390-397页

作者： S.R.Bhongale H.R.Ingawale T.J.Shinde P.n.Vasambekar Department of Physics Yashavantrao Chavan Institute of Science Department of Physics B.V.M.B.S.K.Kanya Mahvidyalaya Department of Physics K.R.P.Kanya Mahvidyalaya Department of Electronics Shivaji University

nd3＋ substituted spinel ferrites with formula MgxCd1-xnd0.03Fe1.97O4（x = 0.0.2,0.4,0.***.0.8 and 1.0）were prepared by oxalate co-precipitation method using novel microwave sintering technique. ar grade sulphates were used as starting chemicals. The samples were sintered at optimized power of 70 W for10 min in a microwave oven（800 W）. The structural analysis of these samples was done by using X-ray diffraction, scanning electron microscope and Fourier transform IR techniques. The XRD analysis of the synthesized ferrite confirms the formation of cubic spinel structure of ferrite. The influence of nd3＋substitution on various structural parameters of Mg-Cd ferrites was reported. IR study indicates the spectra contain two intense absorption bands around 600 and 400 cm^（-1） in addition with four extra bands. The magnetic properties of all ferrites were studied by using a vibration sample *** crystallite and grain size dependant magnetic properties are observed. The composition Mg_（0.6）Cd_（0.4）nd_（0.03）Fe_（1.97）O_4 has better magnetic properties that can be used in recording media. The fast synthesis of spinel ferrites is yielded due to use of the microwave sintering technique.

关键词： Mg-nd-Cd ferrite Rare earth Microwave sintering IR study Coercive force

The performance of the noblesse multi-collector noble gas mass spectrometer for ^(40)ar/^(39)ar geochronology

在线全文

学校读者我要写书评

暂无评论

Acta Geochimica 2018年第5期37卷 734-745页

作者： Defeng He Finlay M.Stuart Dan n.Barfod Fang Xiao Hong Zhong State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Isotope Geoscience Unit Scottish Universities Environmental Research Centre nERC argon Isotope Facility Scottish Universities Environmental Research Centre

noblesse multi-collector noble gas mass spec- trometer is specially designed for multi-collection of ar isotopes with different beam sizes, especially for small ion beams, precisely, and hence is perfectly suitable for ^40ar/^39ar geochronology. We have analyzed widely used sanidine, muscovite, and biotite standards with recom- mended ages of - 1.2-133 Ma, with the aim to assess the reliability of noblesse for ^40ar/^39ar dating. An ESI MIR10 30W CO2 laser was used for total fusion or incremental heating samples. Extracted gases were routinely purified by four SAES nP10 getters （one at - 400 ℃ and others at room temperature）. A GP50 getter and a metal cold finger cooled by liquid n （- 196 ℃） were also attached for additional purification if necessary. The ar isotopes were then measured by noblesse using Faraday or multiplier according to the signal intensities. Over a period of 1.5 months 337 air calibrations produced a weighted mean ^40ar/^36ar of 296.50 ± 0.08 （2σ, MSWD = 4.77）. Fish Canyon sanidine is used to calculate J-values, which show good linear relationship with position in irradiation. The age of four mineral standards （Alder Creek sanidine, Brione muscovite, Yabachi sanidine, and Fangshan biotite） are within error of the accepted ages. Five Alder Creek sanidine aliquots yielded an age range of 1.174-1.181 ± 0.013 Ma （2σ） which broadly overlaps the established age of the standard and the uncertainty approaches those of the foremost ar/ar laboratories in the world. The weighted mean ages of four Brione muscovite aliquots （18.75 i 0.16 Ma, 2σ）, five Yabachi sanidine aliquots （29.50 ± 0.19 Ma, 2σ）, and three Fangshan bio- tite aliquots （133.0 ± 0.76 Ma, 2σ） are consistent with the recommended values of these standards, and the uncer- tainties are typical of modem ar/ar laboratories world- wide.

关键词： ar/ar geochronology Multi-collector Highprecision noblesse Age standard

Systematic investigation of millimeter-wave optic modulation performance in thin-film lithium niobate

在线全文

学校读者我要写书评

暂无评论

Photonics Research 2022年第10期10卷 2380-2387页

作者： YIWEn ZHAnG LInBO SHAO JInGWEI YAnG ZHAOXI CHEn KE ZHAnG KAM-MAn SHUM DI ZHU CHI HOU CHAn MarKO LOnČar CHEnG WAnG Department of Electrical Engineering City University of Hong KongKowloonHong KongChina John A.Paulson School of Engineering and Applied Sciences Harvard UniversityCambridgeMassachusetts 02138USA Bradley Department of Electrical and Computer Engineering Virginia TechBlacksburgVirginia 24061USA State Key Laboratory of Terahertz and Millimeter Waves City University of Hong KongKowloonHong KongChina Institute of Materials Research and Engineering Agency for ScienceTechnology and Research(A^(*)STAR)Singapore 138634Singapore

Millimeter-wave(mmWave)band(30–300 GHz)is an emerging spectrum range for wireless communication,short-range radar,and sensor ***-optic modulators that could efficiently convert mmWave signals into the optical domain are crucial components for long-haul transmission of mmWave signals through optical *** these ultrahigh frequencies,however,the modulation performances are highly sensitive to the transmission line loss as well as the velocity-and impedance-matching conditions,while precise measurements and modeling of these parameters are often *** we present a systematic investigation of the mmWave-optic modulation performances of thin-film lithium niobate modulators through theoretical modeling,electrical verifications,and electro-optic measurements at frequencies up to 325 *** on our experimentally verified model,we demonstrate thin-film lithium niobate mmWave-optic modulators with a measured 3-dB electro-optic bandwidth of 170 GHz and a 6-dB bandwidth of 295 *** device also shows a low RF half-wave voltage of 7.3 V measured at an ultrahigh modulation frequency of 250 *** work provides a comprehensive guideline for the design and characterization of mmWave-optic modulators and paves the way toward future integrated mmWave photonic systems for beyond-5G communication and radar applications.

关键词： millimeter lithium film