检索结果-南通市图书馆

Provenance and tectonic setting of sandstones of the Lomas Coloradas Formation,Cabullona Group,Sonora,México:Constraints on petrography and geochemistry

引用

Journal of Palaeogeography 2024年第4期13卷 839-861页

作者： J.Madhavaraju D.G.noriega-Montoya E.Ramirez-Montoya C.M.Gonzalez-leon John S.Armstrong-Altrin Estacion Regional del noroeste Instituto de GeologiaUniversidad Nacional Autonoma de MexicoHermosilloSonora 83000Mexico Ingenieria en Geociencias Universidad Estatal de SonoraHermosilloSonoraMexico Posgrado en Ciencias de la Tierra Estacion Regional del NoroesteInstituto de GeologiaUniversidad Nacional Autonoma de MexicoHermosilloSonora 83000Mexico Universidad nacional Autonoma de México Instituto de Ciencias del Mar y LimnologiaUnidad de Procesos Oceanicos y CosterosCiudad UniversitariaCiudad de México 04510México

The sedimentary rocks of the Cabullona Group are well exposed in the Cabullona Basin of northeastern Sonora,Mexico,which represent syntectonic sedimentation associated with Laramide-style deformation during the Campanian-early *** sandstones of the Lomas Coloradas Formation deposited at the upper part of the Cabullona *** and geochemical(major,trace,and rare earth elements)studies were carried out on the sandstones to interpret the palaeoweathering,provenance,and tectonic setting of the Lomas Coloradas Formation *** of the sandstone modal analysis data plotted in the QFL and Qm FLt ternary diagrams fall into the fields of dissected arcs and recycled orogens,*** the sandstones are classified as litharenites while few samples plot into the arkosic *** chondrite-normalized REE diagrams for sandstones have LREE-enriched,relatively flat HREE patterns with negative Eu *** values and the A-Cn-K diagram indicate a low intensity of chemical weathering in the source *** tectonic setting diagram suggests both arc and rift settings for the studied *** bivariate and ternary diagrams and elemental ratios suggest a felsic source for the Lomas Coloradas *** average REE patterns of the studied sandstones are comparable with REE patterns of the granite from the Caborca block,the rhyolite and granite of the Tarahumara Formation,and the Mesozoic felsic volcanic *** modeled mixture of 40%Proterozoic granite,30%Triassic arc,10%Jurassic arc,and 20%Laramide arc represents the probable source rocks for the Lomas Coloradas Formation.

关键词： Provenance Petrography Geochemistry Lomas Coloradas Formation Cabullona Group Mexico

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

分体滑动导叶可调涡轮激波与载荷波动机制

引用

中国机械工程 2020年第15期31卷 1778-1786页

作者：杨登峰潘俞舟王贵召老大中 HU leon 东北大学秦皇岛分校控制工程学院秦皇岛066004 国家电投集团周口燃气热电有限公司周口466200 北京理工大学宇航学院北京100081 Ford Motor Company MI 48124 Dearborn USA

针对某柴油机用可调涡轮在低速工况下的低效强激波特征,提出并设计了一种分体滑动导叶,并在10%、40%和100%3个典型开度下进行了定常/非定常数值计算。结果表明:分体滑动导叶在小开度下可实现对间隙泄漏流动的有效抑制,大幅度提高涡轮效... 详细信息

针对某柴油机用可调涡轮在低速工况下的低效强激波特征,提出并设计了一种分体滑动导叶,并在10%、40%和100%3个典型开度下进行了定常/非定常数值计算。结果表明:分体滑动导叶在小开度下可实现对间隙泄漏流动的有效抑制,大幅度提高涡轮效率;在10%开度下,分体滑动导叶提高了涡轮10%的峰值效率,同时涡轮效率在40%和全开工况下也有不同程度的提高。此外,通过合理设计转静间距,分体滑动导叶尾缘激波被大幅度削弱。导叶间隙泄漏流和尾缘激波的抑制可有效弱化转子定子干涉强度,降低下游转子叶片表面载荷波动幅值,提高转子叶片的可靠性。

关键词：可调涡轮分体滑动导叶激波间隙泄漏流载荷波动

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Developmental and genomic architecture of plant embryogenesis: from model plant to crops

引用

Plant Communications 2021年第1期2卷 1-12页

作者： Alma Armenta-Medina C.Stewart Gillmor Peng Gao Javier Mora-Macias leon V.Kochian Daoquan Xiang Raju Datla Global Institute for Food Security University of SaskatchewanSaskatoonSK S7N 4J8Canada Laboratorio nacional de Genòmica para la Biodiversidad(Langebio) Unidad de Genòmica AvanzadaCentro de Investigaciòny Estudios Avanzados del IPN(CINVESTAV-IPN)IrapuatoGuanajuatoMéxico national Research Council Canada 110 Gymnasium PlaceSaskatoonSK S7N 0W9Canada

Embryonic development represents an important reproductive phase of sexually reproducing plant *** fusion of egg and sperm produces the plant zygote,a totipotent cell that,through cell division and cell identity specification in early embryogenesis,establishes the major cell lineages and tissues of the adult *** subsequent morphogenesis phase produces the full-sized embryo,while the late embryogenesis maturation process prepares the seed for dormancy and subsequent germination,ensuring continuation of the plant life *** this review on embryogenesis,we compare the model eudicot Arabidopsis thaliana with monocot crops,focusing on genome activation,paternal and maternal regulation of early zygote development,and key organizers of patterning,such as auxin and WOX transcription *** the early stages of embryo development are apparently conserved among plant species,embryo maturation programs have diversified between eudicots and *** diversification in crop species reflects the likely effects of domestication on seed quality traits that are determined during embryo maturation,and also assures seed germination in different environmental *** review describes the most important features of embryonic development in plants,and the scope and applications of genomics in plant embryo studies.

关键词： embryogenesis embryo patterning zygote genome activation transcription factors genomics transcriptomics

来源：

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

193nm激光引发PET表面的化学接枝

引用

高等学校化学学报 2008年第8期29卷 1655-1659页

作者：吴刚王迎军陈晓峰叶建东魏坤 leon Betty 华南理工大学材料科学与工程学院广州510640 Department of Applied Physics University of Vigovigo36310

将聚对苯二甲酸乙二醇酯[Poly(ethylene terephthalate),PET]材料置于氨气气氛中,利用激光光子同时激发材料表面及氨气形成自由基,用激光引发反应并促进氨基在材料表面的接枝.改性后的测试结果表明,材料表面粗糙度没有显著变化,但水接... 详细信息

将聚对苯二甲酸乙二醇酯[Poly(ethylene terephthalate),PET]材料置于氨气气氛中,利用激光光子同时激发材料表面及氨气形成自由基,用激光引发反应并促进氨基在材料表面的接枝.改性后的测试结果表明,材料表面粗糙度没有显著变化,但水接触角的减小表明表面化学结构发生了某种变化.傅里叶变换红外光谱(FTIR/ATR)图谱在3352和1613cm-1处出现了新的氨基吸收峰,证实了表面接枝了氨基.同时X射线光电子能谱(XPS)也证明了材料表面C—n键的存在,其C1s结合能为285.5 eV,n1s为398.9 eV.飞行时间二次离子质谱(Tof-SIMS)也检测到含氨基的分子碎片,其碎片成像图显示接枝仅发生在激光辐照部位.实验结果表明,激光能在生物材料表面进行局部区域的选择性接枝.

关键词： 193 nm激光表面接枝聚对苯二甲酸乙二醇酯氨基

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A Decreased Expression and Functionality of Muscarinic Cholinergic Receptor in Acute Chagas Myocarditis

引用

World Journal of Cardiovascular Diseases 2014年第6期4卷 305-315页

作者： M. Labrador-hern.n.ez L. Jiménez G. leon R. López W. Mendoza C. Bonfante-Rodriguez J. Torres-Peraza R. Bonfante-Cabarcas Biochemistry Research Unit School of Medicine Universidad Centroccidental “Lisandro Alvarado” Barquisimeto Venezuela Medical Parasitology Research Unit School of Medicine Universidad Centroccidental “Lisandro Alvarado” Barquisimeto Venezuela

Background: Chagas disease is still a public health problem because of the remaining high prevalence, the expansion of the disease into developed countries and the re-emergences by oral transmission outbreaks. Chagas cardiomyopathy evolves as a consequence of an autonomic un-balance where the parasympathetic tone is undermined. Objective: To determine the functionality and expression of muscarinic cholinergic receptors in acute Chagas disease. Methodology: 62 male, 3-week-old Sprague Dawley rats were assayed;32 were infected with Trypanosoma cruzi trypo-mastigotes and 30 were healthy controls. Electrocardiographic studies were conducted in the absence or presence of direct muscarinic (oxotremorine and Mcn-A-343) or indirect agonists (phenylephrine) or antagonist (pirenzepine). Muscarinic M1 and M2 receptor expression was determined by radioligand [3H]-QnB binding assay and immunoblot. Results: Chagasic acute myocarditis was sustained by electrocardiographic signs and histopathological findings. Bradycardia induced by oxotremorine was significantly higher in healthy rats (HR) and the differences were enhanced by CsCl. In the absence of the agonist, CsCl induced a greater bradycardia in chagasic rats (ChR). In HR Mcn-A-343 induced tachycardia, however it induces bradycardia in the presence of a acetylcholinesterase inhibitor (neostigmine);no effects were observed in ChR. Pirenzepine induced a higher tachycardia in HR. Phenylephrine in the presence of pirenzepine induced a similar bradycardia in both groups, but recovery was faster in ChR. Muscarinic M1 and M2 receptor density was higher in HR. Conclusion: Muscarinic receptor expression and functionality are decreased in the acute Chagas disease that could impact the evolution and prognosis of the disease.

关键词： Acute Chagas Disease Muscarinic Receptors Oxotremorine CsCl Mcn-A-343 Phenyleprhine Pirenzepine [3H]-QnB Sprague Dawley Rats

来源：

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

Subsidence associated with land use changes in urban aquifers with intensive extraction

引用

natural Science 2013年第2期5卷 291-295页

作者： Briseida Lopez-Alvarez José Alfredo Ramos-Leal Germán Santacruz-De leon Janete Morán-Ramirez Simón Eduardo Carranco-Lozada Cristina noyola-Medrano Applied Geosciences Division Potosin Institute of Scientific and Technological Research C.A. (IPICYT) San Luís Potosí México Faculty of Engineering University of San Luis Potosí (UASLP) San Luis Potosí México Pg Postgraduate Applied Geoscience Potosin Institute of Scientific and Technological Research C.A. (IPICYT) San Luís Potosí México Water and Society Program College of San Luis C. A. (COLSAN) San Luis Potosí México

Land use change is a major factor in alterations in natural processes and cycles. Remote sensing has become an excellent tool to evaluate technological changes in land cover and land use changes over large areas, such as those occurring in the Valley of San Luis Potosi (VSLP). Here, such changes have impacted a system which is 95% dependent on the aquifer. The methodology for the present study is based on the use of satellite images for the years 1976, 1986, 1995 and 2000. To asses land use change, a supervised classification process was used with a decision tree technique and EnVI 4.3 software. The evolution of groundwater levels for the years 1977, 1986, 1995, 1998 and 2007 was also analyzed, as well as problems of subsidence and fissuring in the urban area of the valley in 2006. With the support of remote sensing, it was possible to analyze the dynamic changes in land use over large areas and highlight their impact on the environment.

关键词： Land Use Change Mining Intensive Extraction Subsidence Aquifer urban Arid Zone

来源：

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

Unilateral Impact of Altered Loading by Changing Teeth Height on the TMJ Fibrocartilage: Disc and Condyle of Wistar Rats

引用

Microscopy Research 2016年第2期4卷 20-31页

作者： Roxanne M. Olvera-Farias Jose Raymundo Cruz-Perez Rogelio Salinas-Gutierrez Jose Antonio Guerrero-Diaz de leon Juan B. Kouri-Flores Raul Rosales-Ibañez David Masuoka Ito Alma Lilian Guerrero Barrera Departamento de Morfología Universidad Autónoma de Aguascalientes Aguascalientes México Departamento de Infectómica y Patogénesis Molecular CInVESTAV-IPn Mexico City Mexico Departamento de Estadística Universidad Autónoma de Aguascalientes Aguascalientes México Departamento de Estomatología Universidad Autónoma de San Luis Potosí San Luis Potosi México Departamento de Estomatología Universidad Autónoma de Aguascalientes Aguascalientes México Laboratorio de Biología Celular y Tisular Departamento de Morfología Universidad Autónoma de Aguascalientes Aguascalientes México

Temporomandibular joint (TMJ) is sensitive to loading and mechanical stress that provokes morphological changes produced by the impact in the occlusal plane. Here, this impact is evaluated in TMJ articular disc and articular cartilage using an in vivo model of unilateral occlusal plane impact and by analysis of serial tissue sections stained with Hematoxylin-Eosin (H-E) or with Masson trichrome technique. Thus, six groups of 5 Wistar rats (200 - 250 g) are subjected to biomechanical dental stimulation by placing unilateral resin occlusal interference, or unilateral tooth wear made by upper left molars artificial mechanical devastation (1 control and 2 experimental groups for each treatment). Each treatment is evaluated two times at 1 and 15 days post-treatment. By H-E staining, control groups show chondrocytes arrangement as several cord cell groups in comparison with the experimental groups, which show an arrangement in one cord cell along of articular disc. However, this yields no significant difference (p n cell number between control and experimental groups. In contrast, in articular cartilage chondrocytes are random distributed along the superficial zone in control groups, while in experimental groups cell-free regions are observed in superficial zone. An image Blue hue analysis for trichrome stain is performed to quantify collagen;this shows a significant collagen decrease (p n almost all experimental groups compared with the controls. A degenerative process biomechanically induced by unilateral occlusal plane modification, causes cell and tissue changes on the TMJ structures that remain the degenerative changes observed in early osteoarthritis.

关键词： Articular Disc Articular Cartilage Dental Occlusion Collagen Temporomandibular Joint

来源：

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

一种用于抄袭识别的文档距离度量

引用

计算机工程与应用 2010年第7期46卷 148-152,177页

作者：胡明晓 DInG leon X 温州大学计算机科学与工程学院浙江温州325035 IBM多伦多实验室

广义编辑距离的计算是一个nP-完全问题,在充分考虑了文档抄袭行为的特点之后提出一种基于广义编辑距离的单向的低计算复杂性的文档距离度量方法。首先,计算第一文档的各段落在第二文档全文中的近似串匹配距离之和,同时确定各段落在第二... 详细信息

广义编辑距离的计算是一个nP-完全问题,在充分考虑了文档抄袭行为的特点之后提出一种基于广义编辑距离的单向的低计算复杂性的文档距离度量方法。首先,计算第一文档的各段落在第二文档全文中的近似串匹配距离之和,同时确定各段落在第二文档中的近似匹配子串(即原象串),然后根据这些原象串得到回退数和前跳数,最后将三者求和作为文档距离。该文档距离是一种广义编辑距离的近似值,能够在O(n2)时间内计算,并能充分反映抄袭方向。针对人工文档和实际文档的两组实验表明该距离具有较低的漏检率、误检率。

关键词：文档距离广义编辑距离近似串匹配抄袭识别电子文档管理

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

梵藏格律诗之比较研究

引用

中国藏学（藏文版） 2021年第1期 110-121页

作者：多杰扎西四川阿坝师范学院

萨班·贡噶坚赞(1182—1251)模仿印度诸论师之格律诗名著,结合藏族本土文化特色撰写了藏族文学史上的第一部格言诗--《萨迦格言》。此著作的问世,开创了藏族格言诗创作之先河,对藏族格律诗的创作和发展起到了举足轻重的作用。文章通过... 详细信息

萨班·贡噶坚赞(1182—1251)模仿印度诸论师之格律诗名著,结合藏族本土文化特色撰写了藏族文学史上的第一部格言诗--《萨迦格言》。此著作的问世,开创了藏族格言诗创作之先河,对藏族格律诗的创作和发展起到了举足轻重的作用。文章通过搜集、整理相关文献资料,试图结合梵藏诸格律诗名著,运用举例说明的方式,从梵藏格律诗的形式、内容和寓言故事等方面进行比较研究,从而指出藏族格言诗是一方面继承和发展了古印度格律诗的创作、另一方面结合藏族本土文化特色对其进行创新和发展的重要成果。

关键词：《萨迦格言》格律诗寓言故事《五卷书》

来源：

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

Gate-controlled supercurrent effect in dry-etched Dayem bridges of non-centrosymmetric niobium rhenium

引用

nano Research 2024年第7期17卷 6575-6581页

作者： Jennifer Koch Carla Cirillo Sebastiano Battisti leon Ruf Zahra Makhdoumi Kakhaki Alessandro Paghi Armen Gulian Serafim Teknowijoyo Giorgio De Simoni Francesco Giazotto Carmine Attanasio Elke Scheer Angelo Di Bernardo Department of Physics University of KonstanzUniversitätsstraße 1078464 KonstanzGermany CnR-Spin c/o Universitàdegli Studi di Salernovia Giovanni Paolo II 13284084 Fisciano(SA)Italy nEST Istituto Nanoscienze-CNR and Scuola Normale SuperiorePiazza San Silvestro 1256127 PisaItaly Dipartimento di Fisica“E.R.Caianiello” Universitàdegli Studi di SalernoVia Giovanni Paolo II 13284084 Fisciano(SA)Italy Advanced Physics Laboratory Institute for Quantum StudiesChapman UniversityBurtonsvilleMD 20866USA

The application of a gate voltage to control the superconducting current flowing through a nanoscale superconducting constriction,named as gate-controlled supercurrent(GCS),has raised great interest for fundamental and technological *** gain a deeper understanding of this effect and develop superconducting technologies based on it,the material and physical parameters crucial for the GCS effect must be ***-down fabrication protocols should also be optimized to increase device scalability,although studies suggest that top-down fabricated devices are more resilient to show a ***,we investigate gated superconducting nanobridges made with a top-down fabrication process from thin films of the noncentrosymmetric superconductor niobium rhenium with varying ratios of the constituents(nbRe).Unlike other devices previously reported and made with a top-down approach,our nbRe devices systematically exhibit a GCS effect when they were fabricated from nbRe thin films with small grain size and etched in specific *** observations pave the way for the realization of top-down-made GCS devices with high *** results also imply that physical parameters like structural disorder and surface physical properties of the nanobridges,which can be in turn modified by the fabrication process,are crucial for a GCS observation,providing therefore also important insights into the physics underlying the GCS effect.

关键词： superconductivity non-centrosymmetric superconductors superconducting devices gated devices gate-controlled supercurrent top-down fabrication

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：