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Gas Quenching Small Components

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材料热处理学报 2004年第5期25卷 494-497页

作者： paul Stratton BOC Sheffield UK

Gas quenching is an environmentally friendly and effective way of quenching components. However it has not been possible to apply it to small components because of the difficulties of jigging. A method of gas quenching such small components is described in which they are levitated in a confined gas stream. The method is suitable for quenching low alloy steel components that weigh between 1 and lOg.

关键词：气体流淬火悬浮低合金钢热处理

On the Contribution of Wu Wen-Tsün to Algebraic Topology

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Journal of Systems Science & Complexity 2019年第1期32卷 3-36页

作者： BRASSELET Jean-paul I2M (CNRS)-Aix-Marseille University

The aim of this article is to present the contribution of Wu Wen-Tsün to Algebraic Topology and more precisely to the theory of characteristic classes. Several papers provide complete and welldocumented biography and academic career of Wu Wen-Tsün, in particular, Hudecek, 2014; O'Connor and Robertson, 2006; Wen-Tsün Wu's Academic Career, 2006; Selected works of Wen-Tsun Wu, *** author does not repeat the details provided in these papers concerning the Wu Wen-Tsün's bibliography, we will just mention people involved in the Wu Wen-Tsün's period in *** addition to Wu Wen-Tsün's papers, the Dieudonné's book(Dieudonné, 1960) provides an excellent presentation of main results of Wu Wen-Tsün in Algebraic and Differential Topology. The author will use and abuse of this book(and refer to) when *** the introduction, the author recalls mainly historical facts concerning the contribution of Wu Wen-Tsün to Algebraic Topology. The second section shows speci?cally the contribution of Wu WenTsün to the Stiefel-Whitney classes and introduces the third section, dealing with the(real) Wu *** author provides de?nition, properties as well as further developments and generalizations of the Wu classes. The fourth and ?fth sections are devoted to recent applications: In Cobordism theory and in Mathematical Physics. The author notices that Wu classes have been used as well in other domains,in particular surgery theory(Madsen and Milgram, 1979). The last section concerns the complex Wu classes and shows that the more recent Mather classes coincide with the previously de?ned complex Wu classes, that is a result from Zhou(1994)(see also Liu, 1996).This article is devoted to the contribution of Wu Wen-Tsün to the theory of Characteristic Classes,which coincides with his "French period"(1947–1951). However, speaking of Algebraic Topology, it is worthwhile to mention the important contribution of Wu Wen-Tsün to the Theory of realization of complexes or manifolds in Eucl

关键词： Algebraic topology characteristic class cobordism theory mathematical physics Wu Class

A Review on Graphene-Based Nanomaterials in Biomedical Applications and Risks in Environment and Health

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Nano-Micro Letters 2018年第3期10卷 164-197页

作者： Thabitha P.Dasari Shareena Danielle McShan Asok k.Dasmahapatra paul B.Tchounwou RCMI Center for Environmental Health Jackson State University

Graphene-based nanomaterials(GBNs) have attracted increasing interests of the scientific community due to their unique physicochemical properties and their applications in biotechnology, biomedicine, bioengineering, disease diagnosis and therapy. Although a large amount of researches have been conducted on these novel nanomaterials, limited comprehensive reviews are published on their biomedical applications and potential environmental and human health effects. The present research aimed at addressing this knowledge gap by examining and discussing:(1) the history, synthesis,structural properties and recent developments of GBNs for biomedical applications;(2) GBNs uses as therapeutics,drug/gene delivery and antibacterial materials;(3) GBNs applications in tissue engineering and in research as biosensors and bioimaging materials; and(4) GBNs potential environmental effects and human health risks. It also discussed the perspectives and challenges associated with the biomedical applications of GBNs.

关键词： Graphene-based nanomaterials Biomedical Delivery Biosensors Tissue engineering Bioimaging Health and environment risks

Jasmonic acid-isoleucine formation in grapevine(Vitis vinifera L.) by two enzymes with distinct transcription profiles

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Journal of Integrative Plant Biology 2015年第7期57卷 618-627页

作者： Christine Bttcher Crista A.Burbidge Valentina di Rienzo paul k.Boss Christopher Davies CSIRO Agriculture Flagship Glen Osmond Department of Soil Plant and Food SciencesSection of Genetics and Plant BreedingUniversity of Bari "Aldo Moro"

The plant hormone jasmonic acid （JA） is essential for stress responses and the formation of reproductive organs, but its role in fruit development and ripening is unclear. Conjugation of JA to isoleucine is a crucial step in the JA signaling pathway since only JA-Ile is recognized by the jasmonate receptor. The conjugation reaction is catalyzed by JA-amido synthetases, belonging to the family of Gretchen Hagen3 （GH3） proteins. Here, in vitro studies of two grapevine （Vitis vinifera L. cv Shiraz） GH3 enzymes, VvGH3-7 and VvGH3-9, demonstrated JA-conjugating activ- ities with an overlapping range of amino acid substrates, including isoleucine. Expression studies of the correspond- ing genes in grape berries combined with JA and JA-lle measurements suggested a primary role for JA signaling in fruit set and cell division and did not support an involvement of JA in the ripening process. In response to methyl JA （MeJA） treatment, and in wounded and unwounded （distal）leaves, VvGH3-9 transcripts accumulated, indicating a participation in the JA response. In contrast, VvGH3-7 was unresponsive to MeJA and local wounding, demonstrating a differential transcriptional regulation of VvGH3-7 and VvGH3- 9. The transient induction of VvGH3-7 in unwounded, distal leaves was suggestive of the involvement of an unknown mobile wound signal.

关键词： Berry development GH3 grapevine jasmonic acid wound response

Materials and sustainable development

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Progress in Natural Science:Materials International 2010年第1期20卷 16-29页

作者： paul kOLTUN CSIRO Process Science and EngineeringGate 5Normanby Rd.ClaytonVictoria3168Australia

Sustainable development is a concept,which involves social,ecological and economic objectives,and requires to sustain the integrity of resources exploitation,the direction of investments,the orientation of technological development and institutional *** there is still much confusion and conflict about exact meaning of sustainable development,many agree that sustainable development is about satisfying social,environmental,and economic *** the concept is generally accepted and relatively easy to comprehend,the difficulty arises in trying to apply the principles of sustainable development in *** of the difficulties is need to measure the"level of sustainability".The desirable characteristics for sustainability indicators have to include: simple to calculate,useful for decision making,and robust in indicating progress toward *** exergy analysis approach based on full life cycle assessment(LCA)of the materials and technologies is a useful metrics to evaluate mitigation of greenhouse gas(GHG)emissions associated with industrial eco materials and *** metrics is used for reducing dimensionality on the input side by combining material and energy streams and output side reducing different characterisation factors to a single"unsustainability"indicator in a theoretically rigorous *** adopted approach has been illustrated on a few examples associated with Australian aluminium industry.

关键词： sustainability measurement exergy analysis life cycle assessment(LCA) eco-efficiency

Plasticity of spermatogonial stem cells

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Asian Journal of Andrology 2015年第3期17卷 355-359页

作者： paul S Cooke Liz Simon Manjunatha k Nanjappa Theresa I Medrano Suzanne E Berry Department of Physiological Sciences College of Veterinary Medicine University of Florida Gainesville FL 32608 USA Department of Physiology Louisiana State University Health Sciences Center New Orleans LA 70112 USA Department of Comparative Biosciences College of Veterinary Medicine University of Illinois at Urbana-Champaign Urbana IL 61802 USA

There have been significant breakthroughs over the past decade in the development and use of pluripotent stem cells as a potential source of cells for applications in regenerative medicine. It is likely that this methodology will begin to play an important role in human clinical medicine in the years to come. This review describes the plasticity of one type of pluripotent cell, spermatogonial stem cells （SSCs）, and their potential therapeutic applications in regenerative medicine and male infertility. Normally, SSCs give rise to sperm when in the testis. However, both human and murine SSCs can give rise to cells with embryonic stem （ES） cell-like characteristics that can be directed to differentiate into tissues of all three embryonic germ layers when placed in an appropriate inductive microenvironment, which is in contrast to other postnatal stem cells. Previous studies have reported that SSCs expressed an intermediate pluripotent phenotype before differentiating into a specific cell type and that extended culture was necessary for this to occur. However, recent studies from our group using a tissue recombination model demonstrated that SSCs differentiated rapidly into another tissue, in this case, prostatic epithelium, without expression of pluripotent ES cell markers before differentiation. These results suggest that SSCs are capable of directly differentiating into other cell types without going through an intermediate ES cell-like stage. Because SSCs do not require reprogramming to achieve a pluripotent state, they are an attractive source of pluripotent cells for use in regenerative medicine.

关键词： pluripotency regenerative medicine spermatogenesis testis

Interface dipole engineering in metal gate/high-k stacks

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Chinese Science Bulletin 2012年第22期57卷 2872-2878页

作者： HUANG AnPing ZHENG XiaoHu XIAO ZhiSong WANG Mei DI ZengFeng CHU paul k Department of Physics Beihang UniversityBeijing 100191China Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 200050China Department of Physics and Materials Science City University ofHong KongTat Chee AvenueKowloonHong KongChina

Although metal gate/high-k stacks are commonly used in metal-oxide-semiconductor field-effect-transistors (MOSFETs) in the 45 nm technology node and beyond,there are still many challenges to be *** the various technologies to tackle these problems,interface dipole engineering (IDE) is an effective method to improve the performance,particularly,modulating the effective work function (EWF) of metal *** of the different electronegativity of the various atoms in the interfacial layer,a dipole layer with an electric filed can be formed altering the band alignment in the MOS *** paper reviews the interface dipole formation induced by different elements,recent progresses in metal gate/high-k MOS stacks with IDE on EWF modulation,and mechanism of IDE.

关键词： IDE接口金属栅偶极子堆叠工程 MOSFET 半导体场效应晶体管技术节点

Using FTIR spectroscopy to detect sericin on historic silk

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Science China Chemistry 2010年第3期53卷 625-630页

作者： WYETH paul Textile Conservation Centre University of Southampton Winchester Campus

Silks represent some of the most precious ancient and historic textile artefacts in collections *** optimum preservation demands an appreciation of their *** important concern,especially with regard to ancient Chinese silks,is whether the fabrics have been *** with remnant sericin gum coating the fibroin fibres would require different conservation *** previous research on aged silks,the presence of sericin has been inferred from amino acid analysis of *** the study reported here,the potential of FTIR spectroscopy to provide a simpler and rapid method of detecting sericin on silk has been *** fibroin and sericin exhibit singular IR *** total reflectance spectroscopy was found to highlight the sericin coating more effectively than transmission and reflectance *** particular peak intensity ratios were identified which might provide a quantitative estimate of the sericin content of new silk,to a sensitivity of 1%-2%.These were also shown to be valid indicators for the presence of sericin on artificially aged and archaeological silks,although quantitation was now not *** the peak intensity ratios,two signature peaks were also seen to be useful markers for silk fibroin,and their presence in a spectrum could be used to infer a degummed silk.

关键词： infrared spectroscopy attenuated total reflectance spectroscopy historic silk

Real-time seismology for the 05/12/2008 Wenchuan earthquake of China: A retrospective view

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Science China Earth Sciences 2009年第2期52卷 155-165页

作者： paul SOMMERVILLE United Research Services Corporation

The devastating 05/12/2008 Wenchuan earthquake (Mw7.9) in Sichuan Province of China showed very few precursory phenomena and occurred on a fault system once assigned to be of moderate long term seismic risk. Given the existing coverage of seismograph stations in Sichuan Province, real-time seis-mology could have been effective in avoiding some earthquake damage and helping post-earthquake emergency response. In a retrospective view, we demonstrated that the epicenter can be located with 20 km accuracy using just two broadband stations with three-component, which takes only about 10 s after the onset of the earthquake. Initial magnitude is estimated to be M7 with the Tc measurement over first 4 seconds of P waves. Better magnitude estimate can be obtained within 2 min by modeling Pnl waves for stations about 500 km away where the S waveforms are clipped. The rupture area is well revealed by teleseismically-recorded >M5 early aftershocks within two hours after the mainshock. Within a few hours, teleseismic body waves were inverted to derive a more detailed rupture process and the finite fault model can be readily used to calculate ground motions, thus providing vital information for rescue efforts in the case where no real-time strong motion records are available.

关键词： real-time seismology earthquake early warning strong ground motion rapid location