维普中文期刊产品整合服务
7406篇 您的检索式:作者名="Hess"
    题名 作者 年代 出处 被引量
1中国与西伯利亚黄土磁化率古气候记录-氧化和还原条件下的两种成土模式分析显示文摘近20多年来随着中国黄土深入研究,揭示了中国黄土地层磁化率与成土古气候温湿程度基本成正比例关系,黄土地层磁化率也因此成为一个重要的古气候参考指标在第四纪古气候研究中,不仅在黄土堆积物而且也在湖相和海相沉积物中广泛应用.但是中国黄土地层磁化率与古土壤成壤强度(古气候温湿程度)呈正比的模式却不是到处都适用,黄土高原的周边地区就有不少例外的报道.而西伯利亚和阿拉斯加黄土则显示出另一极端的情形,一个完全相反的磁化率特点:在气候干冷期的黄土层获高值,而在气候温湿期的古土壤层获低值.过去的研究一直认为,其磁化率主要是反映古风力大小的变化,与成土作用基本无关.磁学测量研究发现,西伯利亚黄土和古土壤的差别,不仅有颗粒从大到小的变化,而且还有矿物组分变化:如磁赤铁矿从多到少,最后完全消失并取而代之出现了完全不同热磁行为的另一种矿物.这种矿物相变现象难以用单纯的风力强弱来解释.说明中国黄土和西伯利亚黄土可能存在两种不同的机制模式:中国黄土高原大部分处于蒸发量大于降雨量的干旱氧化环境,适当的水分或降雨有利于细小的磁铁矿和磁赤铁矿的形成,使得磁化率与古气候呈正比.而西伯利亚以及相应的高纬度地区,地理上属苔原或苔缘地区,湿润是该区域基本特点.间冰期更加温湿的气候使其湿润增加以致过剩,导致地表成土环境向还原方向移动.它使得喜氧化的强磁性矿物磁赤铁矿和磁铁矿渐趋不稳定,并逐渐转化形成适合其还原环境的弱磁性矿物如褐铁矿或其他铁的硫化物.间冰期气候越潮湿,还原程度也越高,强磁性矿物就被损耗得越多.正是这种高纬度的成土作用可能是导致其古土壤磁化率比黄土更低的主导因素之一.刘秀铭 刘东生 夏敦胜 HESSE Paul JIRI Chlachula 王冠 2007中国科学(D辑)2007,37,10:75
2黄土古气候变化趋势与青藏高原隆升关系初探显示文摘粒度和磁化率是两个研究黄土古气候最常用的古环境变化指示参数,它们随着黄上占土壤地层变化而出现峰和谷的对应已经被证明是反映了天文轨道要素的周期变化。文章试图忽略这些受控于轨道要素的气候周期变化,而主要侧重考察黄土地层这两个参数的平均值(或背景值)所反映的长期变化趋势。对兰州九州台黄土进行了系统采样和测量,发现兰州九州台黄土剖面粒度和磁化率曲线显示出两个明显的趋势,粒度从剖面底部向上有明显逐渐变粗趋势,指示着冬季风增强,与此同时,磁化率自下而上却逐渐增大,指示着夏季风增强的趋势。与黄土高原其他黄土剖面磁化率和粒度曲线对比发现,这是两个普遍存在的趋势。地理位置靠近青藏高原的剖面,这两个增大的趋势更明显。冬、夏季风同时逐渐增强是海陆热力差异增大所引起,反映了青藏高原第四纪时期的逐渐不断的隆升过程。因此,根据粒度和磁化率曲线变化趋势线的变化特点可以帮助分析和反推第四纪以来青藏高原隆升的过程。兰州九州台以及黄土高原各剖面粒度和磁化率曲线的线性变化趋势则可能指示着第四纪以来青藏高原是逐渐均匀缓慢的变化过程。我们对22Ma以来风积地层记录的变化趋势也做了分析。前人过去普遍认识的第四纪以来跳跃式或间歇式剧烈隆升在我们的数据中没有得到反映。黄土高原西部西宁、兰州、靖远等剖面磁化率显著的增长趋势可能与青藏高原隆升到一定高度后高原季风加强所致。刘秀铭 毛学刚 丁仲礼 吕镔 郭雪莲 陈渠 陈家胜 贾佳 杨善林 Hesse Paul 陈发虎 2009第四纪研究2009,29,5:45
3Two pedogenic models for paleoclimatic records of magnetic susceptibility from Chinese and Siberian loess显示文摘The magnetic susceptibility (MS) of Chinese loess showing a general proportional relationship to pedogenic grade has been widely recognized and used for reconstruction of paleoclimate by Quaternary scientists. The in-situ pedogenic enhancement of ferrimagnetic content is normally believed to be the main reason for the increase of susceptibility in soil units. However, this pattern of high magnetic susceptibility in palaeosols, and low values in loess, are not replicated in some loess deposits. Siberian loess deposits display a completely opposite susceptibility behavior: high values in loess and low values in palaeosols. This inverse relationship has been explained by the idea that magnetic susceptibility is reflecting the magnitude of an aeolian ferrimagnetic component of consistent mineralogy, the grain size of which is related to average wind velocity. Our magnetic study of Siberian samples in this paper suggests that there are notable differences in magnetic properties between Siberian loess and developed palaeosols, not only in magnetic grain-size and concentration but also in magnetic mineralogy. This evidence is difficult to explain fully through variation in wind strength alone, but implies that the low magnetic susceptibility values in the Siberian paleosol units are a reflection, at least in part, of the alteration of the ferrimagnetic content by post-depositional processes. The Loess Plateau is a very arid area where potential evaporation is always higher than precipitation; pedogenesis occurs under dry oxidising conditions. The Siberian Kurtak region is located on the edge of the tundra where it is always wet and saturation during interglacials will lead to a reducing pedogenic environment. Ferrimagnetic minerals under this condition will be destroyed, resulting in lower magnetic susceptibility. Therefore, great care should be taken when using susceptibility values for paleoclimatic reconstruction.Paul HESSE Jiri CHLACHULA 2008Science China Earth Sciences2008,51,2:25
4磁赤铁矿的几种类型与特点分析显示文摘随着环境磁学的广泛开展和应用,最近20年来磁赤铁矿(γ-Fe2O3)被人们所日益熟悉.现在它已经被发现是一种地表十分常见的矿物,与磁铁矿常常相伴随,是氧化透水通气环境的很好指示矿物.它也是制造音乐和录像磁带的重要磁性材料,在工业有很广泛的用途.磁赤铁矿的人工合成一般由磁铁矿通过在低于300℃的氧化环境中加热几个小时甚至几天时间来形成.它受热不稳定而产生化学变化的磁学性质是其重要特点,即加热到250℃之后该矿物一般就会被不同程度转变成为赤铁矿.因此实际上无法测量其居里点.后来对人工合成磁赤铁矿样品研究进一步发现,该矿物受热可以部分热稳定,居里温度约为645℃.本文通过不同粒度人工磁铁矿系列样品进行热磁测量实验时发现,超细粒级(假单畴(PSD)和多畴(MD)细粒)磁铁矿在快速加热过程中,形成了完全热稳定的磁赤铁矿.而且,用同样的样品在另外加热炉中快速加热到700℃高温,并且在该温度停留10min,然后冷却下来,也可以达到相同的效果.即由此两个过程形成的磁赤铁矿,再从室温加到700℃的居里温度测量过程几乎达到百分之百可逆,即完全对热稳定性特点.我们用X衍射和穆斯堡尔谱技术来鉴定和确认加热前的磁铁矿和快速加热形成的磁赤铁矿(和赤铁矿),并且比较其磁铁矿的磁滞迴线、高温磁化强度、低温热退磁和低温磁化率特性,结果表明,这种过程通过超细磁铁矿加热快速氧化形成完全可逆具有热稳定性质的磁赤铁矿,可能暗示着在某些加热环境形成的磁赤铁矿也可能携带热剩磁.根据磁赤铁矿是否受热不稳定及其表现形式,将它详细分成4种类型探讨分析.受热后部分稳定和完全稳定的磁赤铁矿应当具备携带热剩磁的能力.人工合成磁赤铁矿的温度与其反应时间可能有个互补关系.磁赤铁受热后稳定与否可能与多种因素有关,如受纯度大小、受热温度高低和时间长短等影响,粒度大小可能也是重要因素之一.磁赤铁矿可能如同磁铁矿,也有不同粒级超顺磁(SP)、单畴(SD)和MD对应着不同的磁学特点.细粒PSD氧化的人工磁铁矿在低温磁学测量显示为Verwey转换被'抑制'的现象,其根本原因可能是,氧化后磁铁矿的内核直径实际上已经达到或者接近该矿物的SD粒径,所以它的Verwey转换显得被'抑制'.刘秀铭 John SHAW 蒋建中 Jan BLOEMENDAL Paul HESSE Tim ROLPH 毛学刚 2010中国科学:地球科学2010,40,5:20
5Biodegradable magnesium barrier membrane used for guided bone regeneration in dental surgery显示文摘Barrier membranes are commonly used as part of the dental surgical technique guided bone regeneration(GBR)and are often made of resorbable collagen or non-resorbable materials such as PTFE.While collagen membranes do not provide sufficient mechanical protection of the covered bone defect,titanium reinforced membranes and non-resorbable membranes need to be removed in a second surgery.Thus,biodegradable GBR membranes made of pure magnesium might be an alternative.In this study a biodegradable pure magnesium(99.95%)membrane has been proven to have all of the necessary requirements for an optimal regenerative outcome from both a mechanical and biological perspective.After implantation,the magnesium membrane separates the regenerating bone from the overlying,faster proliferating soft tissue.During the initial healing period,the membrane maintained a barrier function and space provision,whilst retaining the positioning of the bone graft material within the defect space.As the magnesium metal corroded,it formed a salty corrosion layer and local gas cavities,both of which extended the functional lifespan of the membrane barrier capabilities.During the resorption of the magnesium metal and magnesium salts,it was observed that the membrane became surrounded and then replaced by new bone.After the membrane had completely resorbed,only healthy tissue remained.The in vivo performance study demonstrated that the magnesium membrane has a comparable healing response and tissue regeneration to that of a resorbable collagen membrane.Overall,the magnesium membrane demonstrated all of the ideal qualities for a barrier membrane used in GBR treatment.Patrick Rider Zeljka Peric Kacarevic Akiva Elad Drazen Tadic Daniel Rothamel Gerrit Sauer Fabien Bornert Peter Windisch David Botond Hangyasi Balint Molnar Emely Bortel Bernhard Hesse Frank Witte 2022Bioactive Materials2022,7,8:7
6完整街道的完整性评估显示文摘衡量完整街道完整性的工具可以被用于制定政策、决定基础设施投资优先考虑的区域以及如何分配单个街道的路权。回顾了评估完整街道设计最前沿的研究文献。评估完整街道必须先建立基于现实情况的完整性评定标准,而此标准需通过建立街道分类体系将不同类型街道优先体现的功能和预期目标相结合。标准指标体系应体现街道的完整程度,包括交通、环境及场所等要素,同时也应足够灵活,从而能够阐述实现这些功能的各种方法。除极个别外,文献回顾的大多数指标体系都不适合用来评估完整街道,因为这些评估体系大多仅衡量街道是否具备特定的设计要素。另外,一条街道的完整性还可以依据其交通运行、环境和场所方面的标准来评估,也可以与所属街道分类制定的预期目标进行比较。因此,考量一条街道涉及很多因素,如何界定完整街道的优劣及评价指标仍然有许多工作要做。Nancy Hui Shoshanna Saxe Matthew Roorda Paul Hess Eric J.Miller 康浩 2019城市交通2019,17,2:5
7烟碱受体在非洲爪蟾卵母细胞的表达及特征显示文摘分别给非洲爪蟾卵母细胞微量注射电线电器官烟碱型胆碱受体(N_2-ChR)和大鼠脑烟碱型胆碱受体(N_1-ChR)的mRNA,表达出相应的N-ChR。采用全细胞和部分细胞灌流法测定不同浓度氨甲酰胆碱引起的N_2-ChR产生的膜电流,以最小反应模型方程拟合两法所得量反应曲线非常接近。K_1值分别为0.528和0.491mmol·L ̄(-1);Φ ̄(-1)值分别为3.861和3.891。采用全细胞灌流法测得不同浓度氨甲酰胆碱引起的表达N_1-ChR产生的膜电流,拟合所得的量反应曲线较之相应的N2-ChR曲线明显左移。K_1和Φ ̄(-1)值分别为0.140mmol·L ̄(-1)和3.125。陈厚昌 HESS,CP 1994中国药理学与毒理学杂志1994,8,2:5
8The transport geography of logistics and freight distribution显示文摘Markus Hesse Jean-Paul Rodrigue 2003Journal of Transport Geography2003,,3:4
9The Soft X-ray Imager(SXI)on the SMILE Mission显示文摘The Soft X-ray Imager(SXI)is part of the scientific payload of the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission.SMILE is a joint science mission between the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS)and is due for launch in 2025.SXI is a compact X-ray telescope with a wide field-of-view(FOV)capable of encompassing large portions of Earth’s magnetosphere from the vantage point of the SMILE orbit.SXI is sensitive to the soft X-rays produced by the Solar Wind Charge eXchange(SWCX)process produced when heavy ions of solar wind origin interact with neutral particles in Earth’s exosphere.SWCX provides a mechanism for boundary detection within the magnetosphere,such as the position of Earth’s magnetopause,because the solar wind heavy ions have a very low density in regions of closed magnetic field lines.The sensitivity of the SXI is such that it can potentially track movements of the magnetopause on timescales of a few minutes and the orbit of SMILE will enable such movements to be tracked for segments lasting many hours.SXI is led by the University of Leicester in the United Kingdom(UK)with collaborating organisations on hardware,software and science support within the UK,Europe,China and the United States.S.Sembay A.L.Alme D.Agnolon T.Arnold A.Beardmore A.Belén Balado Margeli C.Bicknell C.Bouldin G.Branduardi-Raymont T.Crawford J.P.Breuer T.Buggey G.Butcher R.Canchal J.A.Carter A.Cheney Y.Collado-Vega H.Connor T.Crawford N.Eaton C.Feldman C.Forsyth T.Frantzen G.Galgóczi J.Garcia G.Y.Genov C.Gordillo H-P.Gröbelbauer M.Guedel Y.Guo M.Hailey D.Hall R.Hampson J.Hasiba O.Hetherington A.Holland S-Y.Hsieh M.W.J.Hubbard H.Jeszenszky M.Jones T.Kennedy K.Koch-Mehrin S.Kögl S.Krucker K.D.Kuntz C.Lakin G.Laky O.Lylund A.Martindale J.Miguel Mas Hesse R.Nakamura K.Oksavik N.Østgaard H.Ottacher R.Ottensamer C.Pagani S.Parsons P.Patel J.Pearson G.Peikert F.S.Porter T.Pouliantis B.H.Qureshi W.Raab G.Randal A.M.Read N.M.M.Roque M.E.Rostad C.Runciman S.Sachdev A.Samsonov M.Soman D.Sibeck S.Smit J.Søndergaard R.Speight S.Stavland M.Steller TianRan Sun J.Thornhill W.Thomas K.Ullaland B.Walsh D.Walton C.Wang S.Yang 2024Earth and Planetary Physics2024,8,1:4
10Analysis on variety and characteristics of maghemite显示文摘Maghemite (γ-Fe2O3) is a very common mineral at the earth’s surface and also an important material for making music and video tapes. Maghemite is usually synthesized from magnetite under oxidizing conditions after a few hours or a few days below a temperature of 300°C. The magnetic property of thermal instability and the chemical action after heating is an important character for maghemite. That is, it will become hematite in certain proportion after being heated above 250°C. Maghemite is therefore actually unable to have its Curie temperature measured. But late using synthetic sample, maghemite was further found partially thermal stable with a measurable Curie temperature ~645°C. During our thermally magnetic experiments for a set of synthetic magnetite, we found that extra fined grain size (pseudo single domain (PSD) and small multi-domain (MD), mainly 1-10 μm) magnetite was formed to a completely thermally stable maghemite. This maghemite can also be produced by heating the same powder up to 700°C in an oven and keeping this temperature for 10 min, then cooling it down. When the generated maghemite by these two ways is heated from room temperature to 700°C, it shows almost fully reversible, or thermally stable. We used X-ray powder diffraction and Mssbauer spectroscopy to confirm the identity of this maghemite and compared its magnetic hysteresis, high temperature magnetization, low temperature thermal demagnetization, and low temperature susceptibility with those of the original preheated magnetite. Such quickly oxidized maghemite by heating to high temperature implies some types of maghemite formed in certain natural condition can carry a thermal remnant magnetization (TRM). Four types of maghemite were characterized and discussed according to their thermal stability. Among them, partially stable and fully thermally stable maghemite after heating should possess capability of carrying TRM. There is possibly a compensation of synthetizing maghemite between heating temperature and heating duration. The thermal stability of maghemite may be affected by a few factors, such as its purity (stoichiometry), heating temperature and duration. The grain size may be one of important factors. Maghemite might be similar to magnetite, having various magnetic properties corresponding to its grain size categories such as superparamagnetic (SP), single domain (SD) and MD. Low temperature measurement for PSD fine grain of synthetic magnetite shows a phenomenon of Verwey transition 'suppressed', its fundamental causes could be that the core diameter of oxidized magnetite is actually reach or approach SD size, so that its Verwey transition is shown 'suppressed'.SHAW John BLOEMENDAL Jan HESSE Paul ROLPH Tim 2010Science China Earth Sciences2010,53,8:3
11用于智能照明的LED混色技术显示文摘高亮度LED技术为智能照明领域提供了革新性的发展潜力。我们再不必强迫灯泡达到同一色度的荧光白色,也不必采用复杂的反射镜系统来折射特定的波长。采用LED混色技术所能达到的色彩范围非常强大。正如许多公司已经发现的那样,滞留于以前的解决方案只会让公司自身承担风险,而且,尽管不太情愿,许多公司也正在接受这种发展趋势。Gavin Hesse 2007今日电子2007,,9:3
12Recurrence and Outcomes Following Hepatic Resection, Radiofrequency Ablation, and Combined Resection/Ablation for Colorectal Liver Metastases显示文摘Eddie K. Abdalla Jean-Nicolas Vauthey Lee M. Ellis Vickie Ellis Raphael Pollock Kristine R. Broglio Kenneth Hess Steven A. Curley 2004Annals of Surgery2004,,6:3
13AMP-activated protein kinase is negatively associated with intramuscular fat content in longissimus dorsi muscle of beef cattle显示文摘K.R. Underwood W.J. Means M.J. Zhu S.P. Ford B.W. Hess M. Du 2007Meat Science2007,,2:3
14加拿大北极地区波弗特—马更些盆地伊利石/蒙皂石成岩作用及其与油气分布的关系显示文摘通过陆上和海洋22口探井的215个岩心和岩屑样品的详细研究,建立了波弗特—马更些盆地的伊/蒙(I/S)混层粘土埋藏—成岩作用演化趋势。 波弗特—马更些盆地的伊利石化作用具有四种类型的I/S混层特征:无序、无序和有序混层、R1型有序以及R>1型有序I/S混层。伊利石层的比例一般随深度增加,而I/S混层的主要类型从无序向R>1型有序转变。在无序I/S混层段内伊利石含量增加很快,并随深度呈抛物线性变化趋势,而在有序I/S混层则增加缓慢并呈线性变化趋势。 温度似乎是伊利石化反应的重要控制因素,而超压、岩性及其他地质因素明显对I/S组成的局部变化产生影响。伊利石化反应开始的门限温度高于50℃。从无序向R1型有序转化,从R1型向R>1型有序转化发生的温度分别是70°—110℃和110°—140℃。 超压带和砂岩段内的伊利石化程度比正常压力段和页岩段更高。与正常压力环境相比,超压环境下I/S混层的快速成岩作用,可能与其较高的水/岩比率有关。同理可以解释砂岩段的情况,因为砂岩具有较高的孔隙度和渗透率。 波弗特—马更些盆地的油气分布似乎与I/S成岩作用有关。油气藏位于无序I/S混层段内伊利石化活跃带之上或顶部,而极少位于有序I/S混层出现的深度之下。来自I/S成岩作用的蒙皂石水在油气的富集过程中起着重要的作用。J. Ko R. Hesse 张闻林 王世谦 1999天然气勘探与开发1999,0,2:3
15Experience with 1509 patients undergoing thoracoabdominal aortic operations显示文摘Svensson LG Crawford ES Hess KR Coselli JS Safi HJ 1993J Vasc Surg1993,17,2:2
16利用化学键方法寻找新型光学晶体(英文)显示文摘利用化学键的观点定量地研究了一些具有各种晶体结构实用材料的介电性质。采用已建立的化学键方法 ,分析了这些晶体的介电性质与其组成化学键之间的关系。更进一步 ,基于晶体的化学键方法提出了一个组合方法用于定量确定具有相似晶体结构材料的介电性质。从目前的工作中可以推导出光学晶体非线性起源的结构信息 ,因此可以在一定程度上帮助人们开展非线性光学晶体工程的研究工作。薛冬峰 Betzler Klaus Hesse Hartmut Kitamura Kenji Ratajczak Henryk 王继扬 2004人工晶体学报2004,33,4:2
17Preoperative chemoradiotherapy and postoperative chemotherapy with fluorouracil and oxaliplatin versus fluorouracil alone in locally advanced rectal cancer: initial results of the German CAO/ARO/AIO-04 randomised phase 3 trial显示文摘Claus R?del Torsten Liersch Heinz Becker Rainer Fietkau Werner Hohenberger Torsten Hothorn Ullrich Graeven Dirk Arnold Marga Lang-Welzenbach Hans-Rudolf Raab Heiko Sülberg Christian Wittekind Sergej Potapov Ludger Staib Clemens Hess Karin Weigang-K?hler G 2012Lancet Oncology2012,,7:2
18Positive periodic solutions of predator-prey reaction-diffusion system显示文摘BROWN K I HESS P 1991Nonl Anal TMA1991,16,:2
19Effect of Six-Food Elimination Diet on Clinical and Histologic Outcomes in Eosinophilic Esophagitis显示文摘Amir F. Kagalwalla Timothy A. Sentongo Sally Ritz Therese Hess Suzanne P. Nelson Karan M. Emerick Hector Melin–Aldana B.U.K. Li 2006Clinical Gastroenterology and Hepatology2006,,:2
20饲料混合均匀度对肉鸡生产的重要性显示文摘堪萨斯州立大学的最新研究成果表明了饲料混合均匀度对肉鸡生产性能的重要性。用低浓度雏鸡料饲喂肉鸡至28天,以给予鸡一种轻度营养应激。选择不同混合时间,使雏鸡料混合均匀度变异系数(40.5%CV)差、(12.1%CV)中等和(9.7%CV)充分。与饲喂混合中等或混合充分的雏鸡料相比,肉鸡采食混合差的雏鸡料后,生产性能降低。采食均匀度差的饲料的肉仔鸡,不仅生长速度和饲料转化率下降,而且死亡率升高。Joseph Hess 查红波 蒋金书 1993中国饲料1993,,11:2
返回顶部 每页显示:
共371页 首页 上一页 第1页 下一页 末页 /371 跳转

网站首页 | 关于我们 | 联系我们 | 产品服务 | 客服中心 | 广告服务 | 版权声明 | 网站联盟 | 友情链接 | 售卡网点

版权所有© 渝B2-20050021-1 渝公网安备 50019002500403号 违法和不良信息举报中心

互联网出版许可证 新出网证(渝)字10号 全国400电话 - 免长途话费