نتایج جستجو برای: crystalline rock

تعداد نتایج: 78247  

Journal: :Journal of occupational and environmental hygiene 2013
Eric J Esswein Michael Breitenstein John Snawder Max Kiefer W Karl Sieber

This report describes a previously uncharacterized occupational health hazard: work crew exposures to respirable crystalline silica during hydraulic fracturing. Hydraulic fracturing involves high pressure injection of large volumes of water and sand, and smaller quantities of well treatment chemicals, into a gas or oil well to fracture shale or other rock formations, allowing more efficient rec...

2018

It has been observed that anisotropic nature of rocks is assumed to be caused by disparity in their petrography (mineralogy, texture and micro-structures) including physical properties. These variations have been revealed to occur even in locations where there are only a few centimetres apart on most outcrops. Furthermore, comparable rock types in most localities may not yield the same engineer...

2018

It has been observed that anisotropic nature of rocks is assumed to be caused by disparity in their petrography (mineralogy, texture and micro-structures) including physical properties. These variations have been revealed to occur even in locations where there are only a few centimetres apart on most outcrops. Furthermore, comparable rock types in most localities may not yield the same engineer...

2012

Natural rocks composing the Earth are complex. They consist of an aggregate of one or more minerals. Each mineral can be defined by its chemical composition and its crystalline structure and sometimes can also contain fluid inclusions. Geologists need a powerful characterization technique to get detailed information on the rock formation history. Raman spectroscopy is extremely information-rich...

2009

Natural rocks composing the Earth are complex. They consist of an aggregate of one or more minerals. Each mineral can be defined by its chemical composition and its crystalline structure and sometimes can also contain fluid inclusions. Geologists need a powerful characterization technique to get detailed information on the rock formation history. Raman spectroscopy is extremely information-rich...

Journal: :Philosophical transactions. Series A, Mathematical, physical, and engineering sciences 2010
Elizabeth A Carter Michael D Hargreaves Terence P Kee Matthew A Pasek Howell G M Edwards

A Raman microspectroscopic study of several fulgurites has been undertaken. A fulgurite is an amorphous mineraloid, a superheated glassy solid that is formed when a lightning bolt hits a sandy or rocky ground and thermal energy is transferred. The Raman spectra revealed several forms of crystalline and fused silica and also the presence of polyaromatic hydrocarbons found in an interfacial zone ...

Journal: :Nanotechnology 2009
So Young Jang Han Sung Kim Jeunghee Park Minkyung Jung Jinhee Kim Seung Hyun Lee Jong Wook Roh Wooyoung Lee

Single-crystalline PbTe nanowires were synthesized using the chemical vapor transport method. They consisted of rock-salt structure PbTe nanocrystals uniformly grown in the [100] direction. We fabricated field-effect transistors using a single PbTe nanowire, providing evidence for its intrinsic n-type semiconductor characteristics. The values of the carrier mobility and concentration were estim...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید