Fundamentals of seismic rock physics

Geophysics ◽  
2001 ◽  
Vol 66 (2) ◽  
pp. 398-412 ◽  
Author(s):  
Zhijing (Zee) Wang

During the past 50 years or so, tremendous progress has been made in studying physical properties of rocks and minerals in relation to seismic exploration and earthquake seismology. During this period, many theories have been developed and many experiments have been carried out. Some of these theories and experimental results have played important roles in advancing earth sciences and exploration technologies. This tutorial paper attempts to summarize some of these results.

2004 ◽  
Vol 811 ◽  
Author(s):  
S. Van Elshocht ◽  
B. Brijs ◽  
M. Caymax ◽  
T. Conard ◽  
S. De Gendt ◽  
...  

ABSTRACTGermanium is because of its intrinsically higher mobility than Si, currently under consideration as an alternative approach to improve transistor performance. Germanium oxide, however, is thermodynamically unstable, preventing formation of the gate dielectric by simple oxidation. At present, high-k dielectrics might be considered as an enabling technology as much progress has been made in the deposition of thin high-quality layers.In this paper, we study the growth and physical properties of HfO2 deposited on Ge by MOCVD, using TDEAH and O2 as precursors, and compare the results to similar layers deposited on silicon substrates. Our results show that the physical properties of MOCVD-deposited HfO2 layers on Ge are very similar to what we have observed in the past for Si. Unfortunately, some of the negative aspects observed for Si, such as diffusion of substrate material in the high-k layer, a low density for thinner layers, or a rough top surface, are also observed for the case of Ge. However, careful surface pretreatments such as NH3 annealing the Ge substrate prior to deposition, can greatly improve the physical properties. An important observation is the very thin interfacial layer between HfO2 and Ge substrate, allowing a more aggressive scaling for Ge.


Viruses ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1871
Author(s):  
Naglaa H. Shoukry

Over the past decade, tremendous progress has been made in systems biology-based approaches to studying immunity to viral infections and responses to vaccines. These approaches that integrate multiple facets of the immune response, including transcriptomics, serology and immune functions, are now being applied to understand correlates of protective immunity against hepatitis C virus (HCV) infection and to inform vaccine development. This review focuses on recent progress in understanding immunity to HCV using systems biology, specifically transcriptomic and epigenetic studies. It also examines proposed strategies moving forward towards an integrated systems immunology approach for predicting and evaluating the efficacy of the next generation of HCV vaccines.


2019 ◽  
Vol 98 (11) ◽  
pp. 1173-1182 ◽  
Author(s):  
P.C. Yelick ◽  
P.T. Sharpe

Over the past 100 y, tremendous progress has been made in the fields of dental tissue engineering and regenerative dental medicine, collectively known as translational dentistry. Translational dentistry has benefited from the more mature field of tissue engineering and regenerative medicine (TERM), established on the belief that biocompatible scaffolds, cells, and growth factors could be used to create functional, living replacement tissues and organs. TERM, created and pioneered by an interdisciplinary group of clinicians, biomedical engineers, and basic research scientists, works to create bioengineered replacement tissues that provide at least enough function for patients to survive until donor organs are available and, at best, fully functional replacement organs. Ultimately, the goal of both TERM and regenerative dentistry is to bring new and more effective therapies to the clinic to treat those in need. Very recently, the National Institutes of Health/National Institute of Dental and Craniofacial Research invested $24 million over a 3-y period to create dental oral and craniofacial translational resource centers to facilitate the development of more effective therapies to treat edentulism and other dental-related diseases over the next decade. This exciting era in regenerative dentistry, particularly for whole-tooth tissue engineering, builds on many key successes over the past 100 y that have contributed toward our current knowledge and understanding of signaling pathways directing natural tooth and dental tissue development—the foundation for current strategies to engineer functional, living replacement dental tissues and whole teeth. Here we use a historical perspective to present key findings and pivotal advances made in the field of translational dentistry over the past 100 y. We will first describe how this process has evolved over the past 100 y and then hypothesize on what to expect over the next century.


2014 ◽  
Vol 1 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Franco Giovannelli ◽  
Lola Sabau-Graziati

In this short review paper we comment on some the most important steps that have been made in the past decades for a better understanding of the physics governing our Universe. The results we discuss come from the many groundand-space-based experiments developed for measuring astrophysical sources in various energy bands. These experimental results are discussed within the framework of current theoretical models. Because of the limited length of this paper, we have selected only a few topics that, in our opinion, have been crucial for the progress of our understanding of the physics of cosmic sources.


1937 ◽  
Vol 10 (2) ◽  
pp. 329-335 ◽  
Author(s):  
M. W. Harman

Abstract WITHIN the past few years much progress has been made in the development of rubber vulcanization accelerators of the semi-ultra type which exhibit no prevulcanization or scorch during the preliminary processing. Most of the commercially important members of this class are derivatives of mercaptobenzothiazole in which the hydrogen atom of the mercapto group is replaced by an organic substituent. The increasing use of these products can be attributed to their favorable curing characteristics and to the valuable physical properties which they impart to the cured stock. Naunton and his co-workers (4), Twiss and Jones (8), and Shepard (6) discussed a number of these compounds in recent papers. Numerous references to their preparation and use also appear in the patent literature (1,2,3,5,7,10).


2004 ◽  
Vol 809 ◽  
Author(s):  
S. Van Elshocht ◽  
B. Brijs ◽  
M. Caymax ◽  
T. Conard ◽  
S. De Gendt ◽  
...  

ABSTRACTGermanium is because of its intrinsically higher mobility than Si, currently under consideration as an alternative approach to improve transistor performance. Germanium oxide, however, is thermodynamically unstable, preventing formation of the gate dielectric by simple oxidation. At present, high-k dielectrics might be considered as an enabling technology as much progress has been made in the deposition of thin high-quality layers.In this paper, we study the growth and physical properties of HfO2 deposited on Ge by MOCVD, using TDEAH and O2 as precursors, and compare the results to similar layers deposited on silicon substrates. Our results show that the physical properties of MOCVDdeposited HfO2 layers on Ge are very similar to what we have observed in the past for Si. Unfortunately, some of the negative aspects observed for Si, such as diffusion of substrate material in the high-k layer, a low density for thinner layers, or a rough top surface, are also observed for the case of Ge. However, careful surface pretreatments such as NH3 annealing the Ge substrate prior to deposition, can greatly improve the physical properties. An important observation is the very thin interfacial layer between HfO2 and Ge substrate, allowing a more aggressive scaling for Ge.


2019 ◽  
Vol 17 (11.5) ◽  
pp. 1414-1416
Author(s):  
Richard I. Fisher

Over the past several decades, tremendous progress has been made in the treatment of follicular lymphoma. The addition of rituximab to chemotherapy led to significant improvements in survival in the 1990s. Current standard of care in advanced-stage, previously untreated follicular lymphoma is rituximab plus chemotherapy, sometimes followed by rituximab maintenance. Now, as more research is conducted in the field of chemotherapy-free treatment, Dr. Richard I. Fisher discussed the importance of carefully constructed phase II or III trials at the NCCN 2019 Annual Congress: Hematologic Malignancies. He maintained that a nonchemotherapy treatment regimen comprising rituximab + lenalidomide can be considered in carefully selected patients, and that it is currently the only chemotherapy-free treatment that should be recommended.


1999 ◽  
Vol 5 (S2) ◽  
pp. 24-25
Author(s):  
Kannan M. Krishnan

Tremendous progress has been made in the field of magnetic materials research and technology over the past few years. Superior properties and novel scientific questions arise due to our ability to either synthesize artificial structures or to tailor microstructures at the appropriate length scales. Microstructure, generally defined as the morphological arrangement of crystallites with similar or different phase constitutions and of the crystal defects, is controlled by the processing, which in turn affects the phases present, their topology and their dispersion. There are two key length scales that determine the magnetic behavior of materials. One is the characteristic length scale associated with the dimensional characteristics of the magnetic phenomenon under consideration. The second is the size of the microstructural feature of interest - grain size, shape, isolation, interfaces, inter-granular phases etc. It is important to identify the range where these two length scales overlap, for it is there that novel properties and phenomenon are usually observed.


2014 ◽  
Vol 1073-1076 ◽  
pp. 1104-1107
Author(s):  
Hong Dao Zhang ◽  
Ping Chen ◽  
Jing Zhang ◽  
Ji Di Gao ◽  
Ji Lin Li ◽  
...  

Sustainable agricultural systems tend to have a positive effect on natural, social and human capital, while unsustainable ones feedback to deplete these assets, leaving fewer for future generations. Forage crop are critical to sustainable agriculture and contribute extensively to the world economy. Tremendous progress has been made in genetic transformation of forage and turf grasses in the past decade. The rapida dvancement of cellular and molecular biology and transgenic technology provides novel methods to accelerate and complement conventional breeding efforts. This review summarizes the latest advances of breeding forage crop and introduces the development of sustainable agriculture as well as perspectives the important role of breeding forage crop in development of sustainable agriculture in the future.


Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5174
Author(s):  
Kamil Stańczyk

The dry separation methods for coal beneficiation have been regaining attention in the past decades. A number of improved or newly designed devices have been developed—one of them is a negative pressure pneumatic separator (NPPS). The said method of separation is based on the differences in the physical properties between coal and gangue minerals, such as the grain density, size, and shape. The aim of the hereby presented work was to develop working models describing the operation of the NPPS. To validate the models, the calculation results were compared with experimental results of the tests carried out in the previous study on the topic. Based on the findings it can be inferred that the models accurately predict the separation results, i.e., the majority of results are within the range of estimated measurement uncertainties. Consequently, the models allow one to optimise the process to obtain the products with desirable properties.


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