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热处理技术与装备 1983年第6期 20-28页

作者： J.h.Kaspersma r.h.Shay 朱保华上海机电设计院

1.前言钢的气相渗碳工艺主要包括吸热型气体法和近来出现的几种氮基法。决定这些系统渗碳功能的气氛组成是CO、CO2、h2、h2O和碳氢化合物。在吸热型气体法中,碳氢化合物(常用

关键词：渗碳积炭表面硬化石油产品性质碳氢化合物富化气反应

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核酸的分子结构——脱氧核糖核酸的结构

北京大学学报（自然科学版） 2002年第B12期38卷 53-55,125-126页

作者： J.D.沃森 f.h.C.克里克朱玉贤陈建国医学研究委员会生物大分子结构研究中心

我们希望提出脱氧核糖核酸盐(DNA)的一种结构模式,该结构模式将具有十分重要的生物学意义。本图完全是预测计算后画出来的。两条螺旋表示DNA分子中由磷酸核糖骨架组成的主链,平行的横杠表示碱基配对后产生了用于保持两条DNA链相互结合... 详细信息

我们希望提出脱氧核糖核酸盐(DNA)的一种结构模式,该结构模式将具有十分重要的生物学意义。本图完全是预测计算后画出来的。两条螺旋表示DNA分子中由磷酸核糖骨架组成的主链,平行的横杠表示碱基配对后产生了用于保持两条DNA链相互结合的氢键。垂直的中线表示DNA双螺旋中轴。波林(Pauling)和科里(Corey)已经提出过一种核酸结构并在稿件正式发表之前很友善地供我们参考[1]。他们的模型含有3股相互缠绕的长链,核酸分子中的磷酸基团都位于中心轴的内侧,碱基排布于外侧。我们认为该模型是不能令人满意的,理由如下:(1)我们相信,产生X射线衍射图的是盐,而不是自由核酸。在没有呈酸性的氢原子、尤其是在相互排斥的、带负电荷的磷酸基团都位于DNA长链中心轴附近的情况下,究竟靠什么力量将这种结构保持在一起呢?(2)该模型中某些范德华键的距离似乎太小。弗雷泽(fraser)也提出了一种3股链结构。该模型中磷酸基团位于DNA长链中心轴的外侧,碱基却排布于内侧,由氢键将磷酸与碱基连接在一起。上述结构模式的定义相当不准确,我们不在这里进行评论。我们希望提出一种完全不同的脱氧核糖核酸盐的结构模式。该结构是由相互缠绕的双螺旋链构成并围绕中...

关键词： DNA 结构模式核酸分子结构脱氧核糖核酸

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Chemical synthesis of zinc oxide nanorods for enhanced hydrogen gas sensing

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Chinese Physics B 2014年第1期23卷 509-512页

作者： Musarrat Jabeen Muhammad Azhar Iqbal r Vasant Kumar Mansoor Ahmed Muhammad Tayyeb Javed Department of Physics University of the Punjab Lahore Pakistan Department of Material Science and Metallurgy University of Cambridge England Department of Chemical Engineering Pakistan Institute of Engineering and Applied Sciences Nilore Islamabad Pakistan

Zinc oxide （ZnO） nanorods are prepared using equimolar solution of zinc nitrate （（Zn（NO3）2） and hexamethylenete- tramine （C6hleN4） by the hydrothermal technique at 80 ~C for 12 h. Epitaxial growth is explored by X-ray diffraction （XrD） patterns, revealing that the ZnO nanorods have a hexagonal （wurtzite） structure. Absorption spectra of ZnO are measured by UV-visible spectrometer. The surface morphology is investigated by field emission scanning electron mi- croscopy （fESEM）. The synthesized ZnO nanorods are used for detecting the 150 ~C hydrogen gas with a concentration over 1000 ppm. The obtained results show a reversible response. The influence of operating temperature on hydrogen gas detecting characteristic of ZnO nanorods is also investigated.

关键词： zinc oxide hydrothermal synthesis nanorods hydrogen gas sensor

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Complex interaction of adiponectin-mediated pathways on cancer treatment: a novel therapeutic target

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Journal of Cancer Metastasis and Treatment 2019年第3期4卷 108-130页

作者： Massimo Monks foivos Irakleidis Peng h.Tan UCL Medical School Faculty of Medical ScienceRoyal Free NHS Foundation HospitalLondon NW32QGUK Breast Unit Department of SurgeryRoyal Free NHS Foundation TrustLondon NW32QGUK

Obesity has the far reaching consequence on cancer pathogenesis and immune *** particular,adiponectin(APN)produced by adipocytes played an important role in modulating obesity related *** its interaction with corresponding receptors and their downstream signalling pathways,it regulates cells survival,apoptosis and cancer *** review dissects the clinical evidence on how hypoadiponectinaemia associated with the increased risks of several cancers and the long-term prognosis and also addresses the *** also has its indirect effect on anti-cancer immune response which may influence the disease *** also analyse the impact of APN on the immune system,the anti-tumour responses and the controversies surrounding this *** therapeutics on APN and its receptor axis represents a promising and novel anti-cancer *** understanding of how APN and its interaction with its receptors may affect the immune *** strategizing the use of APN therapeutics in cancer treatment is important,as the APN receptor signalling on the immune cells can blunt anti-tumour *** APN or its receptors has an enormous implication for the treatment of cancers.

关键词： Adiponectin Adipor1/r2 Cancer signaling pathway anti-tumor immunity therapeutic targets

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应变硬化的Al—Mg合金

材料开发与应用 1979年第9期 1-13页

作者： r.h.布朗 M.h.布朗李大超

本文介绍了含4.4—10％Mg、强度水平比退火状态至少提高40％且实质上没有剥落腐蚀敏感性的应变硬化铝合金板材。这种工艺包括根据不同的镁含量在最低为420°—650°f左右的温度下轧制以生产出应变硬化的板材,并且以特殊的控制速度进行... 详细信息

本文介绍了含4.4—10％Mg、强度水平比退火状态至少提高40％且实质上没有剥落腐蚀敏感性的应变硬化铝合金板材。这种工艺包括根据不同的镁含量在最低为420°—650°f左右的温度下轧制以生产出应变硬化的板材,并且以特殊的控制速度进行冷却。

关键词：应变硬化剥落腐蚀开裂性能敏感性腐蚀性能应变强化硬化(金属学) Al Mg

Kinetics of uranium extraction from coffinite——A comparison with other common uranium minerals

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Transactions of Nonferrous Metals Society of China 2018年第10期28卷 2135-2142页

作者： h.S.rEYNOLDS r.rAM M.I.POWNCEBY Y.YANG M.ChEN J.TArDIO L.JONES S.K.BhArGAVA Centre for Advanced Materials and Industrial Chemistry(CAMIC) School of Applied SciencesRMIT UniversityGPO Box 2476Melbourne VIC 3001Australia School of Earth Atmosphere and Environment Monash University9 Rainforest WalkClaytonVictoria 3800Australia CSIrO Mineral resources Private Bag 10 Clayton SouthVictoria 3169Australia

A synthetic coffinite was hydrothermally prepared and characterized before conducting a series of acid sulfate leach tests under conditions of relevance to uranium *** results were then compared with similar studies on synthetic versions of the related U4+minerals uraninite(UO2)and brannerite(UTi2O6)to identify and differentiate the rate and U extraction among these important uranium *** examining the influence of residence time on uranium dissolution from synthetic coffinite,uraninite and brannerite showed that under similar experimental conditions,complete dissolution of uranium from coffinite was obtained between 36 and 48 *** activation energy for this reaction was calculated to be 38.4 kJ/*** represented a significantly slower rate of dissolution than that indicated for uraninite which dissolved in 3 h(Ea=15.2 kJ/mol).The synthetic brannerite was leached at a much slower rate than the coffinite and reached a maximum dissolution of^18%U in 144 h(Ea=42-84 kJ/mol).The clear differentiation in rates and U extraction among the three minerals is consistent with previous literatures which suggest that in terms of leachability,uraninite>coffinite>*** is expected that the presence of impurities in natural coffinites would further inhibit leachability.

关键词： coffinite uraninite brannerite acid leaching extraction kinetics

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Study of the Ionosphere TEC response to the solar flare by GPS observation

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Study of the Ionosphere TEC response to the solar flare by G...

新的血管造影成像平台可减低肝癌病人经动脉化学栓塞治疗时的辐射

第十一届全国日地空间物理学术讨论会

作者： W. Shen, X. h. Deng,Z.G Yuan, r. X. Tang, J. f. Wang, X. M. Zhou Department of Space Physics, Wuhan University, Wuhan, 430079, P. r. China

＜正＞The solar flare effects on the ionosphere have been extensively studied with different observation methods. The dispersive characteristic of the ionosphere makes it possible to measure its total electron content （TEC） based on observations of dual-frequency GPS. The characteristics of the ionospheric response to the solar flares have been studied using the total electron content based on the regional TEC derived from dual-frequency pseudorange and carrier phase network observations of some GPS receiver stations. In this paper, the temporal and spatial variations of the response to the great solar flare on 19 January 2005 is investigated by using network of GPS. We find strong TEC enhancement in the sunlit hemisphere, and the outline of the sunlit ionospheric response to the flare showed the relationship of TEC enhancements with solar zenith angles. The GPS observation has been compared with the Extreme Ultraviolet and X-rays observations, as well as the International reference Ionosphere model （IrI2000）.

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国际医学放射学杂志 2016年第1期 87-88页

作者： r.E.Sch.rnthaner r.Duran J.Chapiro Z.Wang J.f.h.Geschwind M.Lin 刘松 russell h. Morgan Department of radiology and radiological Science Division of Vascular and Interventional Radiology The Johns Hopkins Hospital

摘要目的使用一种新C型臂成像平台,在保持诊断影像质量前提下,量化减少肝癌病人经动脉化学栓塞(TACE)时的辐射。方法该前瞻性研究符合hIPAA并经伦理审查委员会(IrB)批准。在双臂试验中,连续78例原发或继发肝癌病人在升级整合优化采集参... 详细信息

摘要目的使用一种新C型臂成像平台,在保持诊断影像质量前提下,量化减少肝癌病人经动脉化学栓塞(TACE)时的辐射。方法该前瞻性研究符合hIPAA并经伦理审查委员会(IrB)批准。在双臂试验中,连续78例原发或继发肝癌病人在升级整合优化采集参数和提高实时图像处理算法前后,采用一种C型臂成像平台行TACE。记录剂量面积乘积(DAP)和每个数字透视(Df)、数字减影血管造影(DSA)和锥形束CT(CBCT)的曝光时间。DSA影像质量由2名阅片者在4-等级量表上双盲、独立评估。结果 2组队列在病人特征和肿瘤负荷方面无显著差异。和旧平台相比,新系统显著减少

关键词：化学栓塞肝癌病人 TACE 动脉

Transgenic Poplar Plants for the Investigation of ABA-Dependent Salt and Drought Stress Adaptation in Trees

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American Journal of Plant Sciences 2016年第9期7卷 1337-1356页

作者： Domenica hamisch David Kaufholdt Jennifer-Christin Kuch.rnig florian Bittner ralf r. Mendel robert hänsch Jennifer Popko Institut für Pflanzenbiologie Technische Universitat Braunschweig Braunschweig Germany Albrecht-von-haller-Institutfür Pflanzenwissenschaften Abteilung Biochemie der Pflanzen Georg-August-Universitat Gottingen Germany

Important functions of the plant hormone abscisic acid (ABA) in stress reactions, growth and photosynthetic processes are extensively studied in the model plant Arabidopsis thaliana. This paper investigates the importance of Moco-sulphurase ABA3 and aldehyde oxidase (AO) on ABA-biosynthesis in Populus × canescens. ABA3 is essential for activation of the molybdenum enzymes AO and xanthine dehydrogenase (XDh). AO itself catalyzes the last step in ABA-biosynthesis. Generation of transgenic poplar plants altered in ABA3 and AO-activity using rnAi knock down and overexpression was performed. Whereas rnAi-AO plants show a specific loss of AO activity, the rnAi-ABA3 plants has a strongly reduced activity of both molybdenum enzymes: AO and XDh. Constructs of AO and ABA3-promoters fused to β-glucuronidase provide the basis to investigate transcriptional regulation of ABA-biosynthetic processes under stress conditions. Application of high salt concentrations and different drought stress intensities does change the endogenous AO or XDh neither on the side of transcription nor on protein activity. On phytohormone level however, water loss leads to increased ABA-amounts regardless of whether transgenic or wildtype plants are studied. Salt application resulted in higher ABA-levels in all analyzed plant lines. The down regulation of AO in the two different rnAi-plant lines strongly prevented a wildtype-like increase of ABA-levels. Whereas the WT plants accumulated up to 6000 ng ABA g-1 fW-1 after 16 h of salt stress exposure, plants of the rnAi lines revealed a markedly lower increase of only up to 2000 ng ABA g-1 fW-1. Opposing to these observations, ABA-levels increased during drought without any influence by the rnAi-effect. These results revealed that although stresses did not result in a visible increased AO-activity, ABA-production was influenced by AO and ABA3 at least under salinity.

关键词： ABA Biosynthesis Drought Stress Populus × canescens Transgenic Poplar Salt Stress

Steady-state Simulation and Experimental Investigation on Thermal Performance of Air Source heat Pump Using refrigerant Mixture

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Steady-state Simulation and Experimental Investigation on Th...