Abstract:
:The value of NMR spectrometry as a way to understand the porosity and permeability of rocks is well documented. Other more esoteric parameters, such as restrictive diffusion, grain size distribution, and fluid viscosities have received less notice but are also available from the NMR measurements as laboratory studies have shown. With the introduction of gradient field spin-echo NMR well logging, all of these parameters become available in a routine way. To accomplish the goal of having a well log that systematically provides this complete array of NMR answers requires consideration of the measurement principles that can be applied. Magnetic field strength and the relative merits of gradient versus homogeneous magnetic fields methods, as well as the limitations presented by the well bore and wireline systems are a few examples of the factors that must be considered. As important, to the end user, is being provided a definitive link between the well logging response and laboratory measurements on rock samples that prove the meaning of the log. This is ideally accomplished when the laboratory measurements are attained using an apparatus that has the same operating characteristics as the log. For most well logging systems this is seldom accomplished to the degree desired, but it is readily attainable with NMR technologies. The consideration of these factors and the features and benefits of having such a capability are the focus of this paper. The technical attributes of such a comprehensive system, the Numar Corporation's "MRIL" and "CoreSpec1000", plus actual examples of laboratory and well bore data are provided to show the value of such an approach.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Taicher Z,Coates G,Gitartz Y,Berman Ldoi
10.1016/0730-725x(94)91537-7subject
Has Abstractpub_date
1994-01-01 00:00:00pages
285-9issue
2eissn
0730-725Xissn
1873-5894pii
0730-725X(94)91537-7journal_volume
12pub_type
杂志文章abstract::Pelvic MR (41 patients) and CT (36 patients) examinations were performed on 14 females with a primary pelvic complaint, and on 28 females with a suspicion of local recurrent disease of gynecologic malignant tumor. Benign cystic tumors were found in eight patients, five patients had endometriomas, one had a lymphoma, a...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(93)90409-7
更新日期:1993-01-01 00:00:00
abstract::Qualitative and quantitative proton magnetic resonance imaging techniques were applied to persimmon (Diospyros kaki cv 'Fuyu') fruit during development and post-harvest ripening. Spin-lattice (T(1)) relaxation times in mesocarp parenchyma and vascular tissue exhibited a sigmoidal pattern of increase leading to commerc...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(03)00082-1
更新日期:2003-07-01 00:00:00
abstract::The intraductal papillary-mucinous neoplasm (IPMN) is the rarest of the cystic pancreatic tumors. Endoscopic retrograde cholangiopancreatography (ERCP) is currently the gold standard for evaluating IPMN's and can demonstrate dilatation of the main duct or side branches, mural nodules, filling defects, and communicatio...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(01)00440-4
更新日期:2001-10-01 00:00:00
abstract::A variety of shortcomings are associated with most currently used gastrointestinal contrast agents for magnetic resonance imaging (MRI). Artifacts resulting from peristalsis and other motions in the abdominal region are produced by many positive contrast agents (which increase signal intensity). Although this is not a...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(97)00020-9
更新日期:1997-01-01 00:00:00
abstract::Atherosclerotic plaques in the bifurcation of the carotid arteries can pose a significant health risk due to possible plaque rupture and subsequent stroke. The assessment of plaques, and evaluation of the risk they pose, can be performed with Black-Blood (BB) vessel wall magnetic resonance imaging. However, resolution...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2017.04.011
更新日期:2017-07-01 00:00:00
abstract::In the present work, we reported a new nuclear Overhauser enhancement (NOE)-mediated magnetization transfer (MT) signal at around -1.6ppm (NOE(-1.6)) in rat brain and investigated its application in the detection of acute ischemic stroke in rodent model. Using continuous wave (CW) MT sequence, the NOE(-1.6) is reliabl...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2016.05.002
更新日期:2016-10-01 00:00:00
abstract:PURPOSE:Time-of-flight (ToF) and phase contrast (PC) magnetic resonance angiographies (MRAs) are noninvasive applications to depict the cerebral arteries. Both approaches can image the cerebral vasculature without the administration of intravenous contrast. Therefore, it is used in routine clinical evaluation of cerebr...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2012.10.023
更新日期:2013-05-01 00:00:00
abstract::Etched particle tracks produced after heavy ion irradiation of polymer foils are used as model systems to test the performance of NMR in a newly developed ultrahigh magnetic field gradient system. The stimulated NMR echo decay of molecules diffusing in the channels, formulated in terms of the self part of the intermed...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(94)91527-x
更新日期:1994-01-01 00:00:00
abstract::Diffusion in the extracellular and intracellular spaces (ECS and ICS, respectively) was evaluated in excised spinal cords, before and after cell swelling induced by glutamate, by high b-value q-space diffusion MR of specific markers and water. The signal decays of deuterated tetramethylammonium (TMA-d(12)) chloride, a...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2004.01.029
更新日期:2004-06-01 00:00:00
abstract::The relative value of two different MRI procedures for the assessment of infratentorial extension in multiple sclerosis (MS) was studied. Multislice spin-echo techniques were used overall. Procedure A consisted of parasagittal T1-weighted images (500/30) and axial T2-weighted images (2500/30, 2500/120). Procedure B co...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(89)90547-x
更新日期:1989-05-01 00:00:00
abstract::A magnetic resonance imaging (MRI) method is described that allows interleaved measurements of transverse (R(2)(*) and R(2)) and longitudinal (R(1)) relaxation rates of tissue water in conjunction with spin labeling. The image-contrasts are intrinsically blood oxygenation level dependent (BOLD) and cerebral blood flow...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(00)00125-9
更新日期:2000-04-01 00:00:00
abstract::Various analogs of NMR and MRI are now technically possible in optics; specifically, high-resolution laser-pulse shaping and complex pulse sequence generation with well-defined phase shifts has been demonstrated. Here we summarize this technology and discuss the potential for these methods to enhance optical functiona...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2003.08.024
更新日期:2003-12-01 00:00:00
abstract::Gd-DOTA contrast enhancement of MR images was evaluated on induced mammary tumors in female rats. A single intravenous injection of the carcinogenic N-nitrosourea ENU was administered to Wistar rats; this simple treatment led to a high percentage of mammary tumors without causing death. All the induced tumors were ade...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(90)90215-n
更新日期:1990-01-01 00:00:00
abstract::In ultrashort TE (UTE) imaging, the short T2 values of the tissues of interest are comparable to the k-space readout duration, which result in significant T2 decay during k-space readout. This decay consequently causes significant effects on signal and contrast in UTE sequences, which we evaluate in this paper using m...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2013.11.002
更新日期:2014-04-01 00:00:00
abstract::New methods for acquiring and processing gradient NMR well log data enable signals from gas, light oil, and water to be unambiguously separated and, in many cases, quantified. These methods exploit the combined effects of T1-based and diffusion-based contrast on log response. T1 contrast, which separates the water and...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(96)00162-2
更新日期:1996-01-01 00:00:00
abstract::The purpose of this study was to evaluate the value of Ferumoxide-enhanced magnetic resonance (MR) imaging in the detection of hepatic metastases in high-risk patients treated for colorectal cancer that have rising CEA. We used 19 patients treated previously for colorectal cancer with rising CEA levels underwent an un...
journal_title:Magnetic resonance imaging
pub_type: 临床试验,杂志文章
doi:10.1016/s0730-725x(99)00134-4
更新日期:2000-04-01 00:00:00
abstract:PURPOSE:To provide a comprehensive understanding of multi-shot EPI diffusion imaging methods by comparing Readout segmented EPI (RS-EPI) and interleaved EPI (iEPI). MATERIALS AND METHODS:RS-EPI and iEPI were compared on the same 3T scanner. A 2D navigator was used for both RS-EPI and iEPI for phase correction. Signal ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2017.11.011
更新日期:2018-04-01 00:00:00
abstract::Idiopathic dilatation of the pulmonary artery (IDPA) is a rare congenital disease which is usually detected fortuitously on chest x-ray, thus radiologists must be aware of this clinical entity. This report describes four cases to which Magnetic Resonance Imaging (MRI) played a major role in diagnosing IDPA and in dete...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(99)00013-2
更新日期:1999-07-01 00:00:00
abstract::A new magnetic resonance imaging technique was applied to the Taylor-Couette and spiral Poiseuille (Taylor-Couette with superposed mean axial flux) flows for the first time. The experimental technique is a combination of spatial tagging methods and a snapshot FLASH imaging sequence, which allows the full-field visuali...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(99)00121-6
更新日期:2000-02-01 00:00:00
abstract::The ripening of the tomato fruit was delayed for several days (average 5 days) by a 1-day heat treatment at 42 degrees C. Ethylene production increased during the first 3 h, but, after 6 h inhibition was almost total in tomato fruit incubated at 42 degrees C. However, recovery of ethylene production was rapid if fruit...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(98)00219-7
更新日期:1999-06-01 00:00:00
abstract:PURPOSE:Only a few studies have investigated the brain morphology abnormalities in structural MRI in patients with drug-naïve idiopathic generalized epilepsy (IGE) and mainly focused on brain volume changes. In the present study, we aimed to investigate the changes in three morphologic measurement differences including...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2019.05.035
更新日期:2019-09-01 00:00:00
abstract::We compared the ability and reproducibility of a fast fluid-attenuated inversion recovery (fast-FLAIR) sequence with and without a magnetization transfer (MT) pulse for detecting and measuring multiple sclerosis (MS)-related abnormalities on magnetic resonance imaging (MRI) scans from 20 patients. The Contrast-to-Nois...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(98)00182-9
更新日期:1999-04-01 00:00:00
abstract::Pathologically, hippocampal sclerosis (HS) is characterized by neuronal loss and gliosis affecting particularly the pyramidal neurons of CA1, CA3, and CA4 with relative sparing of the CA2 neurons. This can be identified in vivo with magnetic resonance (MR) imaging techniques that can reveal both morphological and sign...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章,评审
doi:10.1016/0730-725x(95)02016-m
更新日期:1995-01-01 00:00:00
abstract:INTRODUCTION:Compared to standard arterial-only first-pass MR-angiography (FPMRA), imaging during the equilibrium phase of a blood pool contrast agent (steady state) has been shown to provide higher image quality and better stenosis grading. Homogenous Dixon fat-suppression promises to increase contrast by suppression ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2015.07.005
更新日期:2015-11-01 00:00:00
abstract::Zero-mean noise introduced into quadrature detected MRI signals is generally rectified by the reconstruction algorithm to give a nonzero background intensity in the displayed image. In low signal-to-noise ratio (SNR) images, this background will inflate region of interest (ROI) signal measurements, leading to improper...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(93)90225-3
更新日期:1993-01-01 00:00:00
abstract::Most modern techniques for functional magnetic resonance imaging (fMRI) rely on blood-oxygen-level-dependent (BOLD) contrast as the basic principle for detecting neuronal activation. However, the measured BOLD effect depends on a transfer function related to neurophysiological changes accompanying electrical neural ac...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2008.02.006
更新日期:2008-11-01 00:00:00
abstract::BOLD-contrast functional magnetic resonance imaging (MRI) was used to assess the evolution of tumor oxygenation and blood flow after administration of four different anesthetics: pentobarbital (60 mg/kg), ketamine/xylazine (80/8 mg/kg), fentanyl/droperidol (0.078/3.9 mg/kg), and isoflurane (1.5%). Gradient echo sequen...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2004.02.005
更新日期:2004-09-01 00:00:00
abstract::Robust voxelwise analysis using tract-based spatial statistics (TBSS) together with permutation statistical method is standardly used in analyzing diffusion tensor imaging (DTI) of brain. A similar analytical method could be useful when studying DTI of cervical spinal cord. Based on anatomical data of sixty-four healt...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2020.07.008
更新日期:2020-11-01 00:00:00
abstract::The chain dynamics of short-chain perfluoropolyether melts confined in Vycor nanoporous media has been characterized by field cycling nuclear magnetic resonance relaxometry and the dipolar correlation effect. The slowdown of motions under confinement, leading to larger residual dipolar couplings, has been probed by lo...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2006.11.018
更新日期:2007-05-01 00:00:00
abstract::T2-weighted images are considered the most sensitive for lesion detection at high field; however, long imaging time is problematic. Accordingly, the authors compared four breath-hold T2 or T2* weighted sequences comprising T2*-weighted FLASH, T2*-weighted PSIF, T2-weighted rapid spin echo (RASE), and T2-weighted Turbo...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(92)90371-6
更新日期:1992-01-01 00:00:00