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Tsinghua Science and Technology 2003年第3期8卷 266-279页

作者： R.Weinstein A.Gandini R.Sawh d.parks Beam Particle dynamics Laboratory Physics Departmentand Texas Center for Superconductivity and Advanced MaterialsUniversity of HoustonHoustonTexas 77204-5005USA

The motivation for continuous columnar pinning centers has been to provide maximum Upin. It has been assumed that this provides the best Jc and Bpin. Limitations on Jc and Spin observed for columnar pinning have been attributed to degradation of the order parameter and Tc. We examine columnar pinning by ionic damage and conclude instead that geometrical effects of columnar pinning on percolation path and on the number of pinning centers are the dominant limitations of columnar pinning, leading to a limit of Bpin- 4 T. Evidence suggests that multiple-in-line-defects (MILd) are far better suited to increase Jc and Bpin. The morphology of MILd pinning is reviewed. Ion energy loss per unit distance, Se, is found to be most promising in a regime almost diametrically opposite to that sought to maximize Upin. We expect Jc - 106 A/cm2 and Bpin > 40T from MILd pinning, despite sharply decreased Upin. Experimental confirmation is proposed.

关键词： improved pinning high critical current high field pinning ionic pinning centers columnar pinning limits

Auroral substorm response to solar wind pressure shock

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Chinese Science Bulletin 2001年第18期46卷 1547-1551,1587页

作者： HONG Minghua WANG Xianmin d.Chua G.parks Institute of Geology and Geophysics Chinese Academy of SciencesBejing 100101China Institute of Space Medico-Engineering Bejing 100094China Geophysics Program University of WashingtonSeattleWA98195USA

Two cases of auroral substorms have been studied with the Polar UVI data, which were associated with solar wind pressure shock arriving at the Earth. The global aurora activities started about 1-2 min after pressure shocks arrived at dayside magnetopause, then nightside auroras intensified rapidly 3-4 min later, with auroral sub-storm onset. The observations in synchronous orbit indicated that the compressing effects on magnetosphere were observed in their corresponding sites about 2 min after the pressure shocks impulse magnetopause. We propose that the auroral intensification and substorm onset possibly result from hydromagnetic wave produced by the pressure shock. The fast-mode wave propagates across the magnetotail lobes with higher local Alfven velocity, magnetotail was compressed rapidly and strong lobe field and cross-tail current were built in about 1-2 min, and furthermore the substorm was triggered due to an instability in current sheet.

关键词： auroral substorm solar wind pressure shock hydro-magnetic wave.

Growth of a Cellular/dendritic Array

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Journal of Materials Science & Technology 1997年第3期13卷 161-172页

作者： J.d.Hunt Q.Hant and X.Wan(dept. of Materials, University of Oxford, parks Road, Oxford OX1 3PH, U.K.) dept. of Materials University of Oxford Oxford OX1 3PH Parks Road United Kingdom

This paper describes a time dependent numerical model for the steady and non-steady growthof a cellular/dendritic array in a moving linear temperature field. The model gives fully selfconsistent solutions for axisymmetric interface shapes, predicts cellular and dendritic spacings,undercoolings and the transition between structures. An important feature of the model is thatthe spacing selection mechanism has been treated. The model predicts two different dendriticgrowth regions. One occurs at low dimensionless velocities where the dendrite array is uniform:a small stable range of spacings is predicted and the prediction agrees very well with existing experiments. The other occurs at high dimensionless velocities where the dendrite array is irregular, its minimum spacing is inversely proportional to velocity Experiment was carried out to verify the prediction. The irregular dendrite array was observed and the measured minimum spacing fitted extremely well with the prediction. By fitting the numerical results. Relatively simple analytic expressions are obtained which provide an insight into the cellular and dendritic growth processes and are useful for comparing theory with experiment.

关键词： Figure Rev Growth of a Cellular/dendritic Array

deformations at Earth’s dayside magnetopause during quasi-radial IMF conditions:Global kinetic simulations and Soft X-ray Imaging

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Earth and Planetary Physics 2024年第1期8卷 59-69页

作者： ZhongWei Yang RiKu Jarvinen XiaoCheng Guo TianRan Sun dimitra Koutroumpa George K.parks Can Huang BinBin Tang QuanMing Lu Chi Wang State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Finnish Meteorological Institute FI-00101 HelsinkiFinland LATMOS/IPSL CNRSUVSQ UniversitéParis-SaclaySorbonne UniversitéGuyancourt78280France Space Sciences Laboratory University of CaliforniaBerkeleyCalifornia 94720USA CAS Engineering Laboratory for deep Resources Equipment and Technology Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029 China deep Space Exploration Laboratory/School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China

The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)is a joint mission of the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS).Primary goals are investigating the dynamic response of the Earth's magnetosphere to the solar wind(SW)impact via simultaneous in situ magnetosheath plasma and magnetic field measurements,X-Ray images of the magnetosheath and magnetic cusps,and UV images of global auroral *** deformations associated with magnetosheath high speed jets(HSJs)under a quasi-parallel interplanetary magnetic field condition are studied using a threedimensional(3-d)global hybrid *** X-ray intensity calculated based on both physical quantities of solar wind proton and oxygen ions is *** obtain key findings concerning deformations at the magnetopause:(1)Magnetopause deformations are highly coherent with the magnetosheath HSJs generated at the quasi-parallel region of the bow shock,(2)X-ray intensities estimated using solar wind h+and self-consistentO7+ions are consistent with each other,(3)Visual spacecraft are employed to check the discrimination ability for capturing magnetopause deformations on Lunar and polar orbits,*** SMILE spacecraft on the polar orbit could be expected to provide opportunities for capturing the global geometry of the magnetopause in the equatorial plane.A striking point is that SMILE has the potential to capture small-scale magnetopause deformations and magnetosheath transients,such as HSJs,at medium altitudes on its *** results also demonstrate that a lunar based imager(e.g.,Lunar Environment heliospheric X-ray Imager,LEXI)is expected to observe a localized brightening of the magnetosheath during HSJ events in the meridian *** preliminary results might contribute to the pre-studies for the SMILE and LEXI missions by providing qualitative and quantitative soft X-ray estimates of dayside kinetic processes.

关键词： collisionless shock SMILE mission foreshock

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极光亚暴对太阳风压强激波的响应

科学通报 2001年第13期46卷 1113-1117,T001页

作者：洪明华王宪民 d.Chua G.parks 中国科学院地质与地球物理研究所北京100101 航天医学工程研究所北京100094 Geophysics Program University of Washington

研究了Ｐｏｌａｒ等对ＩＳＴＰ卫星观测的两个极光亚暴事件，此两事件与日冕物质抛射相关的太阳风压强微波到达地球有关．提出大阳风压强激波经过地球时，沿途冲击磁层顶激发磁流体快波，快Ａｌｆｖｅｎ波横越具有较高局地Ａｌｆｖｅ... 详细信息

研究了Ｐｏｌａｒ等对ＩＳＴＰ卫星观测的两个极光亚暴事件，此两事件与日冕物质抛射相关的太阳风压强微波到达地球有关．提出大阳风压强激波经过地球时，沿途冲击磁层顶激发磁流体快波，快Ａｌｆｖｅｎ波横越具有较高局地Ａｌｆｖｅｎ速度的磁尾尾瓣，将压缩效应迅速传递到内磁层及等离子体片，在１～２ｍｉｎ内建立起强越尾电流，进而触发磁层亚暴．

关键词：极光亚暴太阳风压强激波快Alfven波磁层亚暴触发机制磁层-电离层响应

Extraction of Flavonoids from Bitter Melon

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Food and Nutrition Sciences 2014年第5期5卷 458-465页

作者： Sing Pei Tan Sophie E. parks Costas E. Stathopoulos Paul d. Roach School of Environmental and Life Sciences University of Newcastle Ourimbah Australia School of Environmental and Life Sciences University of Newcastle Ourimbah Australia Central Coast Primary Industries Cen- tre NSW Department of Primary Industries Ourimbah Australia.

Bitter melon, Momordica charantia L, is a popular traditional medicinal fruit in tropical and subtropical countries. It has been linked with therapeutic effects, some of which are likely due to its flavonoids. To determine its total flavonoid content (TFC) and to prepare extracts for use as nutritional supplements or ingredients for nutraceutical functional foods, various solvents have been used, including water, which is the preferred solvent because it is inexpensive, safe and environmentally friendly. The study aimed to extract bitter melon, using five solvents (ethanol, methanol, n-butanol, acetone and water) before and after the optimal conditions for water were determined in terms of extraction temperature, time, ratio of water to bitter melon (mL/g) and number of times the same material was extracted. The TFC of six varieties of bitter melon was also determined. Acetone was the best of the five solvents for extracting flavonoids from the Moonlight variety (23.2 mg Rutin Equivalents (RE)/g). Even after increasing the extraction by 88% (1.24 vs 0.66 mg RE/g) using optimised conditions for the aqueous extraction (two extractions at 40℃ for 15 min at a ratio of 100:1 mL/g of bitter melon powder), the flavonoids extracted from the Moonlight variety using water was very little (5.4%) compared to acetone. Furthermore, using acetone, it was shown that the Moonlight variety (23.2 mg RE/g) bought at a local market had higher levels of flavonoids than the greenhouse-grown Jade (15.3 mg RE/g), Niddhi (16.9 mg RE/g), Indra (15.0 mg RE/ g), Hanuman (3.9 mg RE/g) and White (6.9 mg RE/g) varieties. Therefore, acetone was the best solvent for extracting flavonoids from bitter melon and the aqueous extraction could only be improved to extract 5.4% of the flavonoids extracted with acetone from the Moonlight variety, which had the highest TFC of the six varieties of bitter melon.

关键词： Flavonoids Bitter Melon Acetone Aqueous Extractions

Effects of Ginkgo biloba extracts with mirodenafil on the relaxation of corpus cavernosal smooth muscle and the potassium channel activity of corporal smooth muscle cells

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Asian Journal of Andrology 2011年第5期13卷 742-746页

作者： Jung Jun Kim deok Hyun Han Soo Hyun Lim Tae Hun Kim Mee Ree Chae Kyung Jin Chung Sung Chul Kam Ju-Hong Jeon Jong Kwan parks Sung Won Lee department of Urology Samsung Medical Center Sungkyunkwan University School of Medicine Seou1135-710 Korea department of Urology Gachon University Gil Hospital Incheon 405-760 Korea department of Urology Gyeengsang National University College of Medicine Gyeongsangnam-do 660-702 Korea department of Physiology and Biophysics Seeul National University College of Medicine Seeul 110-799 Korea department of Urology Medical School Chonbuk National University and Institute for Medical Sciences Chonbuk National University and Research Institute and Clinical Trial Center of Medical Device of Chonbuk National University Hospital Jeonju-si 561-712 Korea

In this study, we investigated the effects of a combination of Ginkgo biloba extracts （GBE） and phosphodiesterase type 5 （PdE-5） inhibitors on the muscular tone of the corpus cavernosum and potassium channel activity of corporal smooth muscle cells. Strips of corpus cavernosum from male New Zealand white rabbits were mounted in organ baths for isometric tension studies. After contraction with 1 × 10^-5 mol I^-1 norepinephrine, GBE （0.01-1 mg ml^-1） and mirodenafil （0.01-100 nmol I^-1） were added together into the organ bath. In electrophysiological studies, whole-cell currents were recorded by the conventional patch-clamp technique in cultured smooth muscle cells of the human corpus cavernosum. The corpus cavemosum was relaxed in response to GBE in a dose-dependent manner （from 0.64%±8.35% at 0.01 mg ml^-1 to 52.28%±11.42% at 1 mg ml^-1）. After pre-treatment with 0.03 mg ml^-1 of GBE, the relaxant effects of mirodenafil were increased at all concentrations, After tetraethylammonium （TEA）（1 mmol I^-1） administration, the increased effects were inhibited （P〈0.01）. Extracellular administration of GBE increased the whole-cell K^＋ outward currents in a dose-dependent fashion. The increase of the outward current was inhibited by I mmol 1-1 TEA. These results suggest that GBE could increase the relaxant potency of mirodenafil even at a minimally effective dose. The K＋ flow through potassium channels might be one of the mechanisms involved in this synergistic relaxation.

关键词： calcium-activated potassium channels erectile dysfunction Ginkgo biloba phosphodiesterase inhibitors smooth muscles

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罗斯福一家 1

罗斯福一家

Co-deposition of Co-Ni alloys and their microstructure analysis by PoSAP

丛书名：根据美国普伦蒂斯—霍尔出版社公司1981年版译出

1985年

作者：（美）帕克斯（parks L.R.）辛力译

本书介绍了罗斯福的家庭。

ISBN: (纸本)11203·045

本书介绍了罗斯福的家庭。

关键词：家庭罗斯福,F.d.

来源：汇雅图书（南通市图书馆... 评论

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Chinese Science Bulletin 1997年第23期42卷 2013-2014页

作者： R.A.d.Mackenzie G.d.W.Smith department of Materials University of Oxford Parks Road Oxford OX1 3PH UKDepartment of Materials University of Oxford Parks Road Oxford OX1 3PH UK

PULSEd-co-electrodeposition （PCd） is a new and promising technique for producing alloymaterials of nanometer grain size. In this letter, Co-Ni alloys were produced by PCd, and theeffect of CO+2 ion concentration in the depositing baths on the Co content and the microstruc-ture in the corresponding deposit was studied by the position sensitive atom probe （PoSAP）,TEM and X-ray diffraction. The Co-Ni phase diagram shows that, at room temperature,there are two phases in Co-Ni alloys, one is εCo with hcp lattice, the other is αCo of fcc lat-tice. A Co-Ni alloy with a Ni content below 27% consists of single εCo, beyond 36% consistsof single αCo, in between consists of εCo + αCo. The examination results of TEM, SEM andX-ray diffraction indicated that the Co-Ni deposits with average grain size of 70 nm and thick-

关键词： Co-deposition of Co-Ni alloys and their microstructure analysis by PoSAP Ni

Revitalizing urban spaces: Ten key lessons from the “Viaduc des arts” adaptive reuse and placemaking

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Frontiers of Architectural Research 2024年第5期13卷 1095-1112页

作者： d.Ben Ghida department of Architecture University of Naples Federico Ⅱ NaplesNaplesItaly

This study focuses on the adaptive reuse and placemaking of the Viaduc des Arts,an obsolete viaduct in Paris,and examines its impact on the city’s economic,urban,cultural,and sustainable *** aims to showcase unconventional solutions applied to create an elevated linear park and a coherent commercial identity under the vaults while enhancing the district’s imageability and *** a mixed-methods approach,this study analyzes various action modes in architectural and urban regeneration,highlighting ten valuable lessons learned from the Viaduc des Arts *** lessons provide crucial insights into effective urban regeneration and placemaking strategies,emphasizing the need to update objectives and employ appropriate methodologies for future *** Viaduc des Arts serves as a paradigmatic case study,demonstrating the successful transformation of an obsolete viaduct into a commercial,vibrant cultural,and urban space,underscoring the importance of updating urban regeneration objectives.

关键词： Elevated.parks Urban attractiveness Industrial heritage Urban identity Cultural heritage Building rehabilitation Urban regeneration Adaptive reuse strategies