نتایج جستجو برای: thermal zone

تعداد نتایج: 324433  

Journal: :Science 2003
Jonathon H Stillman

Recent reports have presented meta-analyses of global biological impacts of climate change (1, 2). However, there is debate as to the level of confidence ascribed to the certainty that global climate change has caused the observed biological changes (3). Two important considerations in the assessment of how climate change will impact organisms are (i) how close organisms are to their thermal li...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه پیام نور - دانشگاه پیام نور استان تهران - دانشکده علوم پایه 1390

چکیده: برش مورد مطالعه در 15 کیلومتری جاده ایلام به سمت مهران در منطقه ای تحت عنوان تنگ گراب قرار دارد. سازند گورپی متشکل از سنگهای نرم و تیره رنگ و لیتولوژی نرم بر روی سازند ایلام با سنگهای آهکی سخت و به رنگ سفید و نخودی قرار دارد. در این مطالعه تعداد 51 گونه متعلق به 23 جنس از فرامینیفرهای پلانکتونیک شناسایی و محدوده ی حضور آنها در برش مورد مطالعه تعیین شد. بر این اساس این سازند به 12 بایوزو...

Journal: :Nanoscale 2013
Jiachen Xue Gurpreet Singh Zhe Qiang Alamgir Karim Bryan D Vogt

Surfactant or block copolymer-templated mesoporous films have been extensively explored, but achieving mesostructure coherence and unidirectional orientation over macroscopic dimensions has remained quite challenging for these self-assembled systems. Here, we extend the concepts associated with zone refinement of crystalline materials to soft templated mesoporous carbon films based on the coope...

Journal: :Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine 2004
Tomy Varghese Udomchai Techavipoo James A Zagzebski Fred T Lee

OBJECTIVE Artifacts from gas bubble formation during radio frequency ablation along with the poor intrinsic contrast between normal and treated regions (zone of necrosis) are considerable problems for the visualization of the necrotic region on conventional sonography. Sonographic elastography is very effective for visualizing the zone of necrosis, but it uses the same echo signals to estimate ...

2014
J. Dutta

In this research article a comprehensive investigation has been carried out to determine the effect of thermal cycle on temperature dependent process parameters developed during gas tungsten arc (GTA) welding of high carbon (AISI 1090) steel butt joints. An experiment based thermal analysis has been performed to obtain the thermal history. We have focused on different thermophysical properties ...

2009
Javier Sedano Enrique de la Cal Leticia Curiel José Ramón Villar Emilio Corchado

Improved detection of thermal insulation efficiency in buildings could substantially contribute to reductions in energy consumption and the carbon footprint of domestic heating systems. Thermal insulation standards are now contractual obligations at the construction stage, although they are not standardized in buildings that are already in operation: lighting, occupancy and temperature profiles...

  In this study, a new method for joining aluminum tubes in subsurface structures using steel converting and aluminum welding are presented and reviewed. But near the weld area is under high thermal cycle and will cause residual stresses in heat affected zone. Therefore for assessment of proposed connection from the perspective of residual stress by using the finite element method welding of tu...

Journal: :Integrative and comparative biology 2002
Jonathon H Stillman

Vertical zonation of intertidal organisms, from the shallow subtidal to the supralittoral zones, is a ubiquitous feature of temperate and tropical rocky shores. Organisms that live higher on the shore experience larger daily and seasonal fluctuations in microhabitat conditions, due to their greater exposure to terrestrial conditions during emersion. Comparative analyses of the adaptive linkage ...

1999
JONATHAN E. MARTIN

Separate vector expressions for the rate of change of direction of the potential temperature gradient vector resulting from the geostrophic vorticity and geostrophic deformation, referred to as QVR and QDR, respectively, are derived. The evolution of the thermal structure and forcing for quasigeostrophic vertical motion in an occluded cyclone are investigated by examining the distributions of Q...

2007
Eric Mittelstaedt Michael O. Garcia

[1] Lavas from the early episodes of the Pu`u `Ō`ō eruption (1983–1985) of Kı̄lauea Volcano on the island of Hawai^i display rapid compositional variation over short periods for some episodes, especially the well-sampled episode 30 with 2 wt% MgO variation in <4 hours. Little chemical variation is observed within the episode 30 lavas before or after this abrupt change, suggesting a sharp composi...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید