Study of NMR porosity for terrestrial formation in China

NMR logging is an effective method for porosity measurement. NMR-derived porosity only comes from the pore fluid and is, in principle, not affected by rock matrix. However, it is found that the difference between NMR-derived and conventional log-derived porosities is often between 2 to 6 pu, which is unacceptable, in terrestrial formation in China. In the paper, the theory of NMR porosity was reviewed. The influence factors on NMR porosity error were analyzed based on NMR core measurements. More than 30 core samples with a wide range of porosities including sandstone, limestone and artificial ceramic were chosen for the conventional and NMR porosity measurements. The current NMR data acquisition method was studied based on laboratory NMR core measurements and found to be not good for terrestrial formation. A new NMR data acquisition method suiting for terrestrial formation in China was proposed and much improved the accuracy of NMR porosity measurement. It is suggested that the analysis of core samples from different regions should be carried out before logging in order to obtain accurate NMR porosity.     

稠油储层核磁共振孔隙度校正方法

受原油粘度的影响,利用核磁共振（NMR）测井获取的稠油储层的测井NMR孔隙度远低于地层的真实孔隙度,给稠油储层评价和NMR测井技术的应用带来极大挑战.为提高稠油储层孔隙度计算精度,必须对测井NMR孔隙度进行稠油校正.本研究选取我国南海东部盆地某油田韩江组10块代表性岩心样品,分别开展了原始状态、饱含稠油、残余油和饱含水状态的NMR实验.研究了孔隙含油相对体积对岩心NMR孔隙度的影响,并建立了基于地层深测向电阻率分类的岩心NMR孔隙度校正模型.将基于实验结果建立的岩心NMR孔隙度校正模型推广到实际地层,对目标区域A14井稠油储层实测测井NMR孔隙度进行处理的结果表明：本文提出的方法能够有效地校正孔隙含稠油对实测测井NMR孔隙度的影响,得到地层的真实孔隙度;校正前、后的稠油储层测井NMR孔隙度与常规气驱法测量的岩心孔隙度之间的相对误差由11.19%降低到4.84%.     

川西气田白云岩储层二维核磁共振测井气水识别方法

川西气田雷口坡组四段白云岩储层具有良好的天然气勘探开发前景，但是储层分布具有较强的非均质性，利用常规测井和一维核磁共振测井方法判断储层流体性质存在多解性．通过分析川西雷四段白云岩储层地质特征与测井响应特征，开展岩心二维核磁共振实验，明确了实验室分析与测井过程中环境、参数等影响因素，建立了岩心分析结果的校正方法，明确了钻井液、束缚流体、可动水与天然气信号在二维核磁共振测井中谱分布区间，建立了基于T₂-T₁、T₁/T₂（R）的白云岩储层二维核磁共振测井气水识别图版．利用图版对川西雷四段储层流体性质开展评价，二维核磁共振测井解释结论得到了实钻测试结果的验证，该气水识别方法填补了常规测井、一维核磁共振测井在评价储层气水关系中的缺陷，可有效解决白云岩储层流体性质判别难题．     

井下核磁共振流体分析实验室及其应用

井下流体分析在储层实时评价有十分重要的应用. 该文介绍了NMR流体分析实验室的发展,并以哈里伯顿的井下NMR流体分析实验室为例, 详细讨论了其关键技术,包括探头结构、磁体结构和电路结构,探讨了获取流体核磁共振特性参数的测量方法. NMR流体分析实验室可以获取流体的多种重要参数,结合NMR测井能够进行综合解释,其实时评价性能实现NMR测量的优势.     

氟哌酸β-环糊精包结配合物的研究

氟哌酸是一种广谱、安全、有效,可供口服的抗感染药.我们通过荧光光谱、¹H NMR、¹³C NMR等技术对氟哌酸与β-环糊精(β-CD)的相互作用进行了研究,证明氟哌酸和β-CD形成了包结配合物.包结配合物的生成常数由1D NMR和荧光光谱测量而确定,并由改进的Be-nesi-Hildebrand方法进行了计算,根据这些数据提出了包结配合物的空间构型.     

Development and use of a virtual NMR facility

We have developed a "virtual NMR facility" (VNMRF) to enhance access to the NMR spectrometers in Pacific Northwest National Laboratory's Environmental Molecular Sciences Laboratory (EMSL). We use the term virtual facility to describe a real NMR facility made accessible via the Internet. The VNMRF combines secure remote operation of the EMSL's NMR spectrometers over the Internet with real-time videoconferencing, remotely controlled laboratory cameras, real-time computer display sharing, a Web-based electronic laboratory notebook, and other capabilities. Remote VNMRF users can see and converse with EMSL researchers, directly and securely control the EMSL spectrometers, and collaboratively analyze results. A customized Electronic Laboratory Notebook allows interactive Web-based access to group notes, experimental parameters, proposed molecular structures, and other aspects of a research project. This paper describes our experience developing a VNMRF and details the specific capabilities available through the EMSL VNMRF. We show how the VNMRF has evolved during a test project and present an evaluation of its impact in the EMSL and its potential as a model for other scientific facilities. All Collaboratory software used in the VNMRF is freely available from www.emsl.pnl.gov:2080/docs/collab.     

随钻核磁共振测井仪探测特性研究

随钻核磁共振测井是继电缆核磁共振测井之后的重要进步,具有直接探测原状地层孔隙度、束缚水、渗透率和流体饱和度等特点,受到广泛关注. 随钻核磁共振测井需要在更加恶劣的环境下作业,对探头尤其是对磁体有更高的要求. 该文研究随钻核磁共振测井的探测特性. 基于测量环境和工作方式,分析了随钻核磁共振测井静磁场设计中的特殊问题;利用有限元方法,分别模拟了MRIL-WD（哈里伯顿）、proVISION（斯伦贝谢）和MagTrak（贝克休斯） 3种随钻核磁共振测井仪的静磁场分布;根据数值模拟结果,提出可以抑制仪器随钻具运动（轴向转动、纵向钻进和径向振动）对测量的影响的随钻核磁共振测井静磁场方案,为自主随钻核磁共振测井仪器的设计、实现和优化提供了思路和注意事项.     

Solution NMR spectroscopy of supra-molecular systems, why bother? A methyl-TROSY view

With the development of appropriate labeling schemes and the associated experiments that exploit them it has become possible to record high quality solution NMR spectra of supra-molecular complexes with molecular masses extending to 1MDa. One such approach involves selective (13)CH(3) methyl labeling in highly deuterated proteins using experiments that make use of a methyl-TROSY effect that significantly improves both resolution and sensitivity in spectra. The utility of this methodology has been demonstrated on a growing number of interesting particles. It seems appropriate at this juncture, therefore, to 'step back' and evaluate the role that solution NMR spectroscopy can play in what has traditionally been the domain of X-ray crystallography and more recently cryo-electron microscopy. It is argued here that solution NMR can make a critical contribution to our understanding of how dynamics regulate function in these high molecular weight systems. Several examples from work in my laboratory on the proteasome are presented as an illustration.     

Construction and Implementation of NMR Quantum Logic Gates for Two Spin Systems

The implementation of small prototype quantum computers has been studied through ensemble quantum computing via NMR measurements. In such laboratory studies it is convenient to have access to a wide array of logic gates. Here a systematic approach to reduce the logic gate to an NMR pulse sequence is introduced. This approach views the truth table for a quantum logic operation as a permutation matrix that corresponds to a propagator for an NMR transition. This propagator is then used as the starting point for the derivation of a pulse sequence. Pulse sequences for all the permutations of a four level system are reported along with implementations of representative examples on a two spin-1/2 system, 13C-labeled chloroform.     

氟哌酸-羟丙基环糊精固体包结物的制备及其性质研究

氟哌酸是一种广谱,安全,有效,可供口服的抗感染药.因其在水溶液中溶解度较低,影响肠胃对氟哌酸的吸收,降低了生物利用度.本文通过共沉淀法合成了固体羟丙基-β-环糊精(HP-β-CD)-氟哌酸包结配合物,并经一维,二维核磁共振技术和荧光,差示扫描量热等方法,证明包结物的包结比为1:1,得出包结物的形成常数,并提出包结物的空间构型.     

The Utilization of Nuclear Magnetic Resonance Spectroscopy for Petroleum,Coal, Oil Shale,Petrochemicals, and Polymers. Phenomenology,Paradigms of Applications,and Instrumentation

Abstract

Nuclear Magnetic Resonance (NMR) spectroscopy is now a mature sciezific endeavor that has found many successful applications in a variety of problems in science and technology. Since its discovery in the 1940s, it has developed into a sophisticated but powerful and commonly utilized tool that is found in the analytical laboratory, but also in the pilot plant, the classroom, the highly specialized laboratory, and even in the field.     

High-Resolution NMR of Solids

This chapter is intended to provide a bridge between the principles of NMR spectroscopy of solids and the practical execution of these experiments in the laboratory. The point of view is one of physical concepts, rather than of mathematical rigor. Interwoven with the fundamentals of solid-state NMR are practical tips garnered from laboratory experience. The presentation of material is intended to apply generally to both superconducting and electromagnet geometries. Standard experiments are emphasized, rather than the more exotic and instrument-demanding techniques.

The introduction contrasts the nuclear-spin interactions (Zeeman, dipole–dipole, scalar, chemical shift) in solution and in the solid state. The section on magic-angle spinning examines the effects of mechanical specimen rotation on these nuclear-spin interactions. The concept of dipolar decoupling is introduced next, followed by a section on cross-polarization. Some of the more standard solid-state NMR experiments are described in the section on advanced techniques. Finally, the section on instrumental considerations presents spectrometer and probe requirements for solid-state NMR operation.     

Novel MRI applications of laser-polarized noble gases

Gas-phase nuclear magnetic resonance (NMR) has great potential as a probe for a variety of interesting physical and biomedical problems that are not amenable to study by water or similar liquid. However, NMR of gases was largely neglected due to the low signal obtained from the thermally polarized gases with very low sample density. The advent of optical pumping techniques for enhancing the polarization of the noble gases³He and¹²⁹Xe has bought new life to this field, especially in medical imaging where³He lung inhalation imaging is approaching a clinical application. However, there are numerous applications in materials science that also benefit from the use of these gases. We review primarily nonmedical applications of laser-polarized noble gases for both NMR imaging and spectroscopy and highlight progress with examples from our laboratory including high-resolution imaging at millitesla applied field strength and velocity imaging of convective flow. Porous media microstucture has been probed with both thermal and laser-polarized xenon, as xenon is an ideal probe due to low surface interaction with the grains of the porous media.     

Development and evaluation of magnetic resonance technologies, particularly NMR, for detection of explosives

Beginning in 1972 nuclear magnetic resonance (NMR) technologies for detecting explosives and illegal contraband were developed and evaluated at the Southwest Research Institute. Fullscale systems on the basis of hydrogen transient NMR were developed and evaluated in laboratory and field tests with generally favorable results but with some limitations. These included (1) an experimental, mobile system for detecting buried, nonmetallic land mines; (2) an instrument for inspection of letters and small parcels for small quantities of explosives or illegal drugs; (3) a system for inspection of checked airline baggage and air cargo for concealed explosives and illegal drugs; and (4) a system for rapid inspection of quantities of mail for illegal drugs.¹H NMR offers high sensitivity and detects high-energy explosives such as RDX, TNT, and PETN, as well as nitroglycerine and ammonium-nitrate-based explosives and illegal drugs. Challenges in both physics and engineering were successfully addressed to achieve the goals of rapid inspection with low false-alarm and high detection probability. Electron paramagnetic resonance was found suitable for detecting black powder in laboratory tests as was nuclear quadrupole resonance for a few high-energy explosives. Low-field¹H NMR was also explored in the laboratory to make it practical for explosives detection and found to have potential, but numerous implementation problems must be overcome.     

铁磁物质核磁共振自旋回波的激发和接收条件的分析及其验证

分析了不同物理条件下铁磁材料中核磁共振效应的激发、自旋回波讯号的形成和接收过程并进行了实验验证。所得结果合理地说明了实验条件对铁磁体核磁共振测量的影响,也指出了改进自旋回波接收方法的途径。     

多维核磁共振波谱学

核磁共振波谱学自本世纪40年代中期诞生起,已走完了其光辉的50年历程,其间,它已完成了自连续波检测向脉冲傅里叶变换检测的过渡,并在此基础上率先将传统的一维谱的观测拓宽为多维谱的观测,不断提供了其它方法难以提供或无法提供的崭新信息,从而确立了它在分子结构和动力学研究中的独特地位,本文旨在以二维NMR为主,简述被称为现代核磁共振波谱学之核心的多维NMK的概况。     

核磁共振量子信息处理研究的新进展

过去的二十年中,量子信息相关研究取得了显著的进展,重要的理论和实验工作不断涌现.与其他量子信息处理系统相比,基于自旋动力学的核磁共振系统,不仅具有丰富而且成熟的控制技术,还拥有相干时间长、脉冲操控精确、保真度高等优点.这也是核磁共振体量子系统能够精确操控多达12比特的量子系统的原因.因此,核磁共振量子处理器在量子信息领域一直扮演着重要角色.本文介绍核磁共振量子计算的基本原理和一些新研究进展.研究的新进展主要包括量子噪声注入技术、量子机器学习在核磁共振平台上的实验演示、高能物理和拓扑序的量子模拟以及核磁共振量子云平台等.最后讨论了液态核磁共振的发展前景和发展瓶颈,并对未来发展方向提出展望.     

T1-relaxation of 129Xe on metal single crystal surfaces-multilayer experiments on iridium and monolayer considerations

The surface of a typical laboratory single crystal has about 10(15) surface atoms or adsorption sites, respectively, and is thus far out of reach for conventional NMR experiments using thermal polarization. It should however be in reach for NMR of adsorbed laser polarized (hyperpolarized) 129Xe, which is produced by spin transfer from optically pumped rubidium. With multilayer experiments of xenon adsorbed on an iridium surface we do not only demonstrate that monolayer sensitivity has been obtained, we also show that such surface experiments can be performed under ultra high vacuum conditions with the crystal being mounted in a typical surface analysis chamber on a manipulator with far-reaching sample heating and cooling abilities. With only four spectra summed up we present an NMR signal from at most 4x10(14) atoms of 129Xe, four layers of naturally abundant xenon, respectively. The fact that no monolayer signal has been measured so far is explained by a fast Korringa relaxation due to the Fermi contact interaction of the 129Xe nuclei with the electrons of the metal substrate. T(1)-relaxation times in the order of several ms have been calculated using all electron density functional theory for several metal substrates.