Science.gov

Sample records for qiu ping li

  1. Retraction Statement: 'MicroRNA-218 increases cellular sensitivity to Rapamycin via targeting Rictor in cervical cancer' by Li J, Wang J, Wang Y, Qiu H.

    PubMed

    2017-02-01

    The above article from APMIS, published online on 24 April 2015 in Wiley Online Library (wileyonlinelibrary.com) and in Volume 123, pp. 562-570, has been retracted by agreement between the authors, the journal Editors in Chief, Professors Bodil Norrild, Ben Vainer and Elisabeth Ralfkiaer, and John Wiley & Sons Ltd. The article has been retracted due to errors in the reported results. In this study, the authors used HeLa and SiHa cell lines to investigate the biological roles of miR-218. However, subsequently it emerged that the two cell lines were contaminated in the laboratory by other unknown cell lines. When repeating the experiments, it was found that the functions of miR-218 were not as significant as had been previously reported, especially its effects on rapamycin sensitivity. Reference Li J, Li X, Wang J, Wang Y, Qiu H. MicroRNA-218 increases cellular sensitivity to Rapamycin via targeting Rictor in cervical cancer. APMIS 2015; 123:562-570. doi: 10.1111/apm.12387.

  2. Ping-pong auto-zero amplifier with glitch reduction

    DOEpatents

    Larson, Mark R.

    2008-01-22

    A ping-pong amplifier with reduced glitching is described. The ping-pong amplifier includes a nulling amplifier coupled to a switching network. The switching network is used to auto-zero a ping amplifier within a ping-pong amplifier. The nulling amplifier drives the output of a ping amplifier to a proper output voltage level during auto-zeroing of the ping amplifier. By being at a proper output voltage level, glitches associated with transitioning between a ping amplifier and a pong amplifier are reduced or eliminated.

  3. Impact of a ping-pong ball

    NASA Astrophysics Data System (ADS)

    Cross, Rod

    2017-05-01

    Measurements are presented of the impact time, peak force and centre of mass displacement of a ping-pong ball impacting vertically on a hard, horizontal surface. The results are compared with a recent measurement described in this journal.

  4. Complete Subsurface Elemental Composition Measurements With PING

    NASA Technical Reports Server (NTRS)

    Parsons, A. M.

    2012-01-01

    The Probing In situ with Neutrons and Gamma rays (PING) instrument will measure the complete bulk elemental composition of the subsurface of Mars as well as any other solid planetary body. PING can thus be a highly effective tool for both detailed local geochemistry science investigations and precision measurements of Mars subsurface reSOurces in preparation for future human exploration. As such, PING is thus fully capable of meeting a majority of both ncar and far term elements in Challenge #1 presented for this conference. Measuring the ncar subsurface composition of Mars will enable many of the MEPAG science goals and will be key to filling an important Strategic Knowledge Gap with regard to In situ Resources Utilization (ISRU) needs for human exploration. [1, 2] PING will thus fill an important niche in the Mars Exploration Program.

  5. On a possible node in the Sivers and Qiu-Sterman functions

    NASA Astrophysics Data System (ADS)

    Boer, Daniël

    2011-08-01

    The possibility of a node in the x dependence of the Sivers and Qiu-Sterman functions is discussed in light of its importance for the experimental check of the overall sign change of the Sivers effect between semi-inclusive DIS and the Drell-Yan process. An x-dependent version of the Ehrnsperger-Schäfer-Greiner-Mankiewicz relation between the Qiu-Sterman function and a twist-3 part of g2 is presented, which naturally suggests a node in the Qiu-Sterman function. This relation could be checked experimentally as well and could provide qualitative information on the gluonic field strength inside the proton. Satisfying the Burkardt sum rule by means of a node is briefly discussed and the importance of modelling the Sivers function including its full Wilson line is pointed out.

  6. PingER History and Methodology

    SciTech Connect

    Cottrell, L

    2003-10-01

    This paper describes the methodology of the PingER toolkit/project. It provides some examples of how the results have been used to identify evolutionary changes in WAN response times and connectivity quality over the past 10 years, as well as some of the challenges faced in maintaining and deploying the system.

  7. [Development idea and practice of Qiu Mao-liang's acupuncture diagnosis and treatment].

    PubMed

    Zhao, Jing-sheng

    2014-11-01

    Professor Qiu Mao-liang is considered as one of the representatives in the renaissance and development of acupuncture and moxibustion in the 20th century, whose academic characteristics could be summarized as "sticking to tradition and absorbing new knowledge". The practice ideas, methods and influence factors that were presented in acupuncture clinical practice are analyzed in this paper, from which development tendency and practice pattern of modern acupuncture clinical practice are discussed.

  8. Launch Creativity with Ping-Pong Ball Challenge

    ERIC Educational Resources Information Center

    Kornoelje, Joanne; Roman, Harry T.

    2011-01-01

    Educators at Thomas A. Edison Middle School have worked together to bring invention information and activities to life. One activity in particular, Ping-Pong Ball Invention Challenge, has proven a great success. The Ping-Pong Ball Invention Challenge was inspired by the basic rules for PBS's "Design Squad"'s "Pop Fly" activity. In this article,…

  9. Launch Creativity with Ping-Pong Ball Challenge

    ERIC Educational Resources Information Center

    Kornoelje, Joanne; Roman, Harry T.

    2011-01-01

    Educators at Thomas A. Edison Middle School have worked together to bring invention information and activities to life. One activity in particular, Ping-Pong Ball Invention Challenge, has proven a great success. The Ping-Pong Ball Invention Challenge was inspired by the basic rules for PBS's "Design Squad"'s "Pop Fly" activity. In this article,…

  10. Measuring the Digital Divide with PingER

    SciTech Connect

    Cottrell, L.

    2003-10-01

    We introduce the PingER project/toolkit and show its relevance to monitoring sites in developing countries. We then show results from PingER that illustrate the extent of the Digital Divide in terms of Internet performance between developed and developing regions, which developing regions are catching up, keeping up, or falling behind and the magnitude of the differences in performance between developed regions and developing regions.

  11. Calculation of weighted averages approach for the estimation of ping tolerance values

    USGS Publications Warehouse

    Silalom, S.; Carter, J.L.; Chantaramongkol, P.

    2010-01-01

    A biotic index was created and proposed as a tool to assess water quality in the Upper Mae Ping sub-watersheds. The Ping biotic index was calculated by utilizing Ping tolerance values. This paper presents the calculation of Ping tolerance values of the collected macroinvertebrates. Ping tolerance values were estimated by a weighted averages approach based on the abundance of macroinvertebrates and six chemical constituents that include conductivity, dissolved oxygen, biochemical oxygen demand, ammonia nitrogen, nitrate nitrogen and orthophosphate. Ping tolerance values range from 0 to 10. Macroinvertebrates assigned a 0 are very sensitive to organic pollution while macroinvertebrates assigned 10 are highly tolerant to pollution.

  12. The physics of juggling a spinning ping-pong ball

    NASA Astrophysics Data System (ADS)

    Widenhorn, Ralf

    2016-12-01

    Juggling a spinning ball with a ping-pong paddle represents a challenge both in terms of hand-eye coordination and physics concepts. Here, we analyze the ping-pong ball's motion, and explore how the correct paddle angle relates to the ball's spin and speed, as it moves vertically up and down. For students, this requires engaging with concepts like momentum, angular momentum, free-body diagrams, and friction. The activities described in this article include high-speed video motion tracking of the ping-pong ball and the investigation of the frictional characteristics of the paddle. They can be done in a physics lab or at home, requiring only inexpensive or commonly used equipment, and can be undertaken by high school or college students.

  13. Big Hydrophobic Capillary Fluidics; Basically Water Ping Pong in Space

    NASA Astrophysics Data System (ADS)

    Weislogel, Mark; Attari, Babak; Wollman, Andrew; Cardin, Karl; Geile, John; Lindner, Thomas

    2016-11-01

    Capillary surfaces can be enormous in environments where the effects of gravity are small. In this presentation we review a number of interesting examples from demonstrative experiments performed in drop towers and aboard the International Space Station. The topic then focuses on large length scale hydrophobic phenomena including puddle jumping, spontaneous particle ejections, and large drop rebounds akin to water ping pong in space. Unseen footage of NASA Astronaut Scott Kelly playing water ping pong in space will be shown. Quantitative and qualitative results are offered to assist in the design of experiments for ongoing research. NASA NNX12A047A.

  14. Subsurface In Situ Elemental Composition Measurements with PING

    NASA Technical Reports Server (NTRS)

    Parsons, Ann; McClanahan, Timothy; Bodnarik, Julia; Evans, Larry; Nowicki, Suzanne; Schweitzer, Jeffrey; Starr, Richard

    2013-01-01

    This paper describes the Probing In situ with Neutron and Gamma rays (PING) instrument, that can measure the subsurface elemental composition in situ for any rocky body in the solar system without the need for digging into the surface. PING consists of a Pulsed Neutron Generator (PNG), a gamma ray spectrometer and neutron detectors. Subsurface elements are stimulated by high-energy neutrons to emit gamma rays at characteristic energies. This paper will show how the detection of these gamma rays results in a measurement of elemental composition. Examples of the basalt to granite ratios for aluminum and silicon abundance are provided.

  15. [Professor Qiu Mao-Liang's theory of "three benefits" of acupuncture for diseases of digestive system].

    PubMed

    Wu, Zhong-Chao; He, Chong

    2012-04-01

    Professor QIU Mao-Iiang is a famous Chinese physician of acupuncture and Chinese medicine in modern time and is one of representative figure of Chengijang acupuncture schools. The theory of "three benefits" of acupuncture for diseases of disgestive system is established according to pathogenesis. He holds that acupuncture is favorable in removing the stagnated liver qi, reinforcing the functions of the spleen and the stomach in treatment of gastroduodenal ulcer. For problems due to spleen deficiency, reinforcing method should be given to the main points, Back-shu points and Yuan-primary points, while reducing method should be given to Front-mu points. Deficiency type of chronic gastritis is much more seen than excessive type. Therefore, the treating principle of acupuncture shoujd be tonifying the spleen and dispeling the cold. Removing the liver qi and regulating qi circulation can be applied in phases. And for special cases, method of tonifying the stomach yin should be used. For gastroptosis, reinforcing qi in the middle jiao should be applied generally. For those with qi stagnation, qi in middle jiao should be regulated. For retention of food and dampness, treatment should focus on removing phlegm and dampness. And the following points can be selected to lift the stomach by long needle, Juque (CV 14), Liangmen (ST 21) and the acupoints around stomach. For treatment of diarrhea, toward the three pathological factors of dampness, heat and cold, treatment of removing dampness, clearing heat and dispelling cold, especially the first one should be applied, and others are selected by differentiation of syndromes. And for gallstone, treating principle should be established according to the theory of qi stagnation, disharmony between the gallbladder and the sto-mach as well as obstruction by substantial pathogens. And regulation of qi, relieving pain, regulating the functions of the gallbladder and the stomach should be applied so as to removing calculus. Professor QIU

  16. Washington Commentary: Endless Ping-Pong over Math Education

    ERIC Educational Resources Information Center

    Lewis, Anne C.

    2005-01-01

    Ever since the charter school movement became big news, Anne C. Lewis has refrained from writing about it very much because it seemed more like covering each hit in a Ping-Pong game. As study and counter-study rolled off the presses and into the press releases, the substance became less and less relevant. Each new study was always sure to be…

  17. Moment of Inertia of a Ping-Pong Ball

    ERIC Educational Resources Information Center

    Cao, Xian-Sheng

    2012-01-01

    This note describes how to theoretically calculate and experimentally measure the moment of inertia of a Ping-Pong[R] ball. The theoretical calculation results are in good agreement with the experimental measurements that can be reproduced in an introductory physics laboratory.

  18. Intelligent Management of Intelligence Agencies: Beyond Accountability Ping-Pong

    ERIC Educational Resources Information Center

    Tetlock, Philip E.; Mellers, Barbara A.

    2011-01-01

    The intelligence community (IC) is asked to predict outcomes that may often be inherently unpredictable--and is blamed for the inevitable forecasting failures, be they false positives or false negatives. To move beyond blame games of accountability ping-pong that incentivize bureaucratic symbolism over substantive reform, it is necessary to reach…

  19. Moment of Inertia of a Ping-Pong Ball

    ERIC Educational Resources Information Center

    Cao, Xian-Sheng

    2012-01-01

    This note describes how to theoretically calculate and experimentally measure the moment of inertia of a Ping-Pong[R] ball. The theoretical calculation results are in good agreement with the experimental measurements that can be reproduced in an introductory physics laboratory.

  20. Intelligent Management of Intelligence Agencies: Beyond Accountability Ping-Pong

    ERIC Educational Resources Information Center

    Tetlock, Philip E.; Mellers, Barbara A.

    2011-01-01

    The intelligence community (IC) is asked to predict outcomes that may often be inherently unpredictable--and is blamed for the inevitable forecasting failures, be they false positives or false negatives. To move beyond blame games of accountability ping-pong that incentivize bureaucratic symbolism over substantive reform, it is necessary to reach…

  1. Washington Commentary: Endless Ping-Pong over Math Education

    ERIC Educational Resources Information Center

    Lewis, Anne C.

    2005-01-01

    Ever since the charter school movement became big news, Anne C. Lewis has refrained from writing about it very much because it seemed more like covering each hit in a Ping-Pong game. As study and counter-study rolled off the presses and into the press releases, the substance became less and less relevant. Each new study was always sure to be…

  2. Single-ping ADCP measurements in the Strait of Gibraltar

    NASA Astrophysics Data System (ADS)

    Sammartino, Simone; García Lafuente, Jesús; Naranjo, Cristina; Sánchez Garrido, José Carlos; Sánchez Leal, Ricardo

    2016-04-01

    In most Acoustic Doppler Current Profiler (ADCP) user manuals, it is widely recommended to apply ensemble averaging of the single-pings measurements, in order to obtain reliable observations of the current speed. The random error related to the single-ping measurement is typically too high to be used directly, while the averaging operation reduces the ensemble error of a factor of approximately √N, with N the number of averaged pings. A 75 kHz ADCP moored in the western exit of the Strait of Gibraltar, included in the long-term monitoring of the Mediterranean outflow, has recently served as test setup for a different approach to current measurements. The ensemble averaging has been disabled, while maintaining the internal coordinate conversion made by the instrument, and a series of single-ping measurements has been collected every 36 seconds during a period of approximately 5 months. The huge amount of data has been fluently handled by the instrument, and no abnormal battery consumption has been recorded. On the other hand a long and unique series of very high frequency current measurements has been collected. Results of this novel approach have been exploited in a dual way: from a statistical point of view, the availability of single-ping measurements allows a real estimate of the (a posteriori) ensemble average error of both current and ancillary variables. While the theoretical random error for horizontal velocity is estimated a priori as ˜2 cm s-1 for a 50 pings ensemble, the value obtained by the a posteriori averaging is ˜15 cm s-1, with an asymptotical behavior starting from an averaging size of 10 pings per ensemble. This result suggests the presence of external sources of random error (e.g.: turbulence), of higher magnitude than the internal sources (ADCP intrinsic precision), which cannot be reduced by the ensemble averaging. On the other hand, although the instrumental configuration is clearly not suitable for a precise estimation of turbulent

  3. [Doctor HUANG Shi-ping's acupuncture with golden needles].

    PubMed

    Chen, Teng-Fei; Ma, Zeng-Bin; Xin, Si-Yuan; Zhu, Jiang

    2013-08-01

    Taking Doctor HUANG Shi-ping as the representative, the school of Huang's golden needle is based on Chinese martial art. Golden needles are adopted as main tool. Attaching great importance on the combination of acupuncture and moxibustioin, it is also characterized with penetrating needling with long needles. Through the development of three generations, it once outshone other schools in the field of acupuncture, and became famous all over the world. It made great contribution to the development of the course of acupuncture. However, with the development of the history, the form of acupuncture education as well as apparatus were all undergone an unified reform. Therefore, Doctor HUANG Shi-ping's acupuncture school be lost gradually.

  4. The Pediatric Imaging, Neurocognition, and Genetics (PING) Data Repository.

    PubMed

    Jernigan, Terry L; Brown, Timothy T; Hagler, Donald J; Akshoomoff, Natacha; Bartsch, Hauke; Newman, Erik; Thompson, Wesley K; Bloss, Cinnamon S; Murray, Sarah S; Schork, Nicholas; Kennedy, David N; Kuperman, Joshua M; McCabe, Connor; Chung, Yoonho; Libiger, Ondrej; Maddox, Melanie; Casey, B J; Chang, Linda; Ernst, Thomas M; Frazier, Jean A; Gruen, Jeffrey R; Sowell, Elizabeth R; Kenet, Tal; Kaufmann, Walter E; Mostofsky, Stewart; Amaral, David G; Dale, Anders M

    2016-01-01

    The main objective of the multi-site Pediatric Imaging, Neurocognition, and Genetics (PING) study was to create a large repository of standardized measurements of behavioral and imaging phenotypes accompanied by whole genome genotyping acquired from typically-developing children varying widely in age (3 to 20 years). This cross-sectional study produced sharable data from 1493 children, and these data have been described in several publications focusing on brain and cognitive development. Researchers may gain access to these data by applying for an account on the PING portal and filing a data use agreement. Here we describe the recruiting and screening of the children and give a brief overview of the assessments performed, the imaging methods applied, the genetic data produced, and the numbers of cases for whom different data types are available. We also cite sources of more detailed information about the methods and data. Finally we describe the procedures for accessing the data and for using the PING data exploration portal.

  5. The Pediatric Imaging, Neurocognition, and Genetics (PING) Data Repository

    PubMed Central

    Jernigan, Terry L.; Brown, Timothy T.; Hagler, Donald J.; Akshoomoff, Natacha; Bartsch, Hauke; Newman, Erik; Thompson, Wesley K.; Bloss, Cinnamon S.; Murray, Sarah S.; Schork, Nicholas; Kennedy, David N.; Kuperman, Joshua M.; McCabe, Connor; Chung, Yoonho; Libiger, Ondrej; Maddox, Melanie; Casey, B. J.; Chang, Linda; Ernst, Thomas M.; Frazier, Jean A.; Gruen, Jeffrey R.; Sowell, Elizabeth R.; Kenet, Tal; Kaufmann, Walter E.; Mostofsky, Stewart; Amaral, David G.; Dale, Anders M.

    2015-01-01

    The main objective of the multi-site Pediatric Imaging, Neurocognition, and Genetics (PING) study was to create a large repository of standardized measurements of behavioral and imaging phenotypes accompanied by whole genome genotyping acquired from typically-developing children varying widely in age (3 to 20 years). This cross-sectional study produced sharable data from 1493 children, and these data have been described in several publications focusing on brain and cognitive development. Researchers may gain access to these data by applying for an account on the PING Portal and filing a Data Use Agreement. Here we describe the recruiting and screening of the children and give a brief overview of the assessments performed, the imaging methods applied, the genetic data produced, and the numbers of cases for whom different data types are available. We also cite sources of more detailed information about the methods and data. Finally we describe the procedures for accessing the data and for using the PING data exploration portal. PMID:25937488

  6. Improving security of the ping-pong protocol

    NASA Astrophysics Data System (ADS)

    Zawadzki, Piotr

    2013-01-01

    A security layer for the asymptotically secure ping-pong protocol is proposed and analyzed in the paper. The operation of the improvement exploits inevitable errors introduced by the eavesdropping in the control and message modes. Its role is similar to the privacy amplification algorithms known from the quantum key distribution schemes. Messages are processed in blocks which guarantees that an eavesdropper is faced with a computationally infeasible problem as long as the system parameters are within reasonable limits. The introduced additional information preprocessing does not require quantum memory registers and confidential communication is possible without prior key agreement or some shared secret.

  7. The plant MITE mPing is mobilized in anther culture.

    PubMed

    Kikuchi, Kazuhiro; Terauchi, Kazuki; Wada, Masamitsu; Hirano, Hiro-Yuki

    2003-01-09

    Transposable elements constitute a large portion of eukaryotic genomes and contribute to their evolution and diversification. Miniature inverted-repeat transposable elements (MITEs) constitute one of the main groups of transposable elements and are distributed ubiquitously in the genomes of plants and animals such as maize, rice, Arabidopsis, human, insect and nematode. Because active MITEs have not been identified, the transposition mechanism of MITEs and their accumulation in eukaryotic genomes remain poorly understood. Here we describe a new class of MITE, called miniature Ping (mPing), in the genome of Oryza sativa (rice). mPing elements are activated in cells derived from anther culture, where they are excised efficiently from original sites and reinserted into new loci. An mPing-associated Ping element, which has a putative PIF family transposase, is implicated in the recent proliferation of this MITE family in a subspecies of rice.

  8. Sonar inter-ping noise field characterization during cetacean behavioral response studies off Southern California

    NASA Astrophysics Data System (ADS)

    Guan, Shane; Southall, Brandon L.; Vignola, Joseph F.; Judge, John A.; Turo, Diego

    2017-03-01

    The potential negative effects of sound, particularly active sonar, on marine mammals has received considerable attention in the past decade. Numerous behavioral response studies are ongoing around the world to examine such direct exposures. However, detailed aspects of the acoustic field (beyond simply exposure level) in the vicinity of sonar operations both during real operations and experimental exposures have not been regularly measured. For instance, while exposures are typically repeated and intermittent, there is likely a gradual decay of the intense sonar ping due to reverberation that has not been well described. However, it is expected that the sound field between successive sonar pings would exceed natural ambient noise within the sonar frequency band if there were no sonar activity. Such elevated sound field between the pings may provide cues to nearby marine mammals on source distances, thus influencing potential behavioral response. Therefore, a good understanding of the noise field in these contexts is important to address marine mammal behavioral response to MFAS exposure. Here we investigate characteristics of the sound field during a behavioral response study off California using drifting acoustic recording buoys. Acoustic data were collected before, during, and after playbacks of simulated mid-frequency active sonar (MFAS). An incremental computational method was developed to quantify the inter-ping sound field during MFAS transmissions. Additionally, comparisons were made between inter-ping sound field and natural background in three distinctive frequency bands: low-frequency (<3 kHz), MFA-frequency (3-4.5 kHz), and high-frequency (>4.5 kHz) bands. Results indicate significantly elevated sound pressure levels (SPLs) in the inter-ping interval of the MFA-frequency band compared to natural background levels before and after playbacks. No difference was observed between inter-ping SPLs and natural background levels in the low- and high

  9. Bitz, Ginoux, Jacobson, Nizkorodov, and Yang Receive 2013 Atmospheric Sciences Ascent Awards: Citation for Ping Yang

    NASA Astrophysics Data System (ADS)

    Webster, Peter J.

    2014-07-01

    The Atmospheric Sciences section of AGU awards one of the five Ascent Awards to Professor Ping Yang of the Department of Atmospheric Sciences at Texas A&M University for significant contributions to atmospheric scattering, radiative transfer, and remote sensing.

  10. Artificial "ping-pong" cascade of PIWI-interacting RNA in silkworm cells.

    PubMed

    Shoji, Keisuke; Suzuki, Yutaka; Sugano, Sumio; Shimada, Toru; Katsuma, Susumu

    2017-01-01

    PIWI-interacting RNAs (piRNAs) play essential roles in the defense system against selfish elements in animal germline cells by cooperating with PIWI proteins. A subset of piRNAs is predicted to be generated via the "ping-pong" cascade, which is mainly controlled by two different PIWI proteins. Here we established a cell-based artificial piRNA production system using a silkworm ovarian cultured cell line that is believed to possess a complete piRNA pathway. In addition, we took advantage of a unique silkworm sex-determining one-to-one ping-pong piRNA pair, which enabled us to precisely monitor the behavior of individual artificial piRNAs. With this novel strategy, we successfully generated artificial piRNAs against endogenous protein-coding genes via the expected back-and-forth traveling mechanism. Furthermore, we detected "primary" piRNAs from the upstream region of the artificial "ping-pong" site in the endogenous gene. This artificial piRNA production system experimentally confirms the existence of the "ping-pong" cascade of piRNAs. Also, this system will enable us to identify the factors involved in both, or each, of the "ping" and "pong" cascades and the sequence features that are required for efficient piRNA production.

  11. A homogeneous ping-pang architecture for SAR real-time imaging

    NASA Astrophysics Data System (ADS)

    Xu, Jia; Peng, Yingning; Li, Jun; Wang, Xiutan

    2005-11-01

    Based on the range-Doppler imaging algorithm, a novel homogeneous ping-pang architecture is proposed for synthetic aperture radar (SAR) real time imaging. Different from the normal heterogeneous pipeline architecture, almost the identical design on hardware and software is adopted by the two ping-pang nodes. Therefore, more scalable and efficient performance may be obtained for the proposed design with a balanced computational load, and it is especially suitable to be implemented via the commercial-off-the-shelf (COTS) platform.

  12. Table Tennis, Anyone? Using Ping-Pong To Teach the Coordinate Plane.

    ERIC Educational Resources Information Center

    Foshay, John D.; Wells, Wendy L.

    1997-01-01

    Presents a ping-pong activity to teach the coordinate plane that puts students in a position to experience and relate to the coordinate plane in a manner that evokes their visual, spatial, and physical senses while linking the plane with a familiar object. (ASK)

  13. Taking a Swat at Physics with a Ping-Pong Paddle.

    ERIC Educational Resources Information Center

    Graney, Chris M.

    1994-01-01

    A professor of physics discusses ideas on how to use physics to improve your ping-pong game. Describes how basic physics was used to analyze a simple ball-paddle collision problem and provide students with insight on the application of physics to a fun and real life situation. (ZWH)

  14. Creating Accessible Science Museums with User-Activated Environmental Audio Beacons (Ping!)

    ERIC Educational Resources Information Center

    Landau, Steven; Wiener, William; Naghshineh, Koorosh; Giusti, Ellen

    2005-01-01

    In 2003, Touch Graphics Company carried out research on a new invention that promises to improve accessibility to science museums for visitors who are visually impaired. The system, nicknamed Ping!, allows users to navigate an exhibit area, listen to audio descriptions, and interact with exhibits using a cell phone-based interface. The system…

  15. Sustaining improvement? The 20-year Jönköping quality improvement program revisited.

    PubMed

    Staines, Anthony; Thor, Johan; Robert, Glenn

    2015-01-01

    There is scarce evidence of organization-wide and sustained impact of quality improvement (QI) programs in health care. For 20 years, the Jönköping County Council's (Sweden) ambitious program has attracted attention from practitioners and researchers alike. This is a follow-up case of a 2006 study of Jönköping's improvement program, triangulating data from 20 semi-structured interviews, observation and secondary analysis of internal performance data. In 2010, clinical outcomes had clearly improved in 2 departments (pediatrics, intensive care), while process improvements were evident in many departments. In an overall index of the 20 Swedish county councils' performance, Jönköping had improved its ranking since 2006 to lead in 2010. Five key issues shaped Jönköping's improvement program since 2006: a rigorously managed succession of chief executive officer; adept management of a changing external context; clear strategic direction relating to integration; a broadened conceptualization of "quality" (incorporating clinical effectiveness, patient safety, and patient experience); and continuing investment in QI education and research. Physician involvement in formal QI initiatives had increased since 2006 but remained a challenge in 2010. A new clinical information system was being deployed but had not yet met expectations. This study suggests that ambitious approaches can carry health care organizations beyond the sustainability threshold.

  16. Creating Accessible Science Museums with User-Activated Environmental Audio Beacons (Ping!)

    ERIC Educational Resources Information Center

    Landau, Steven; Wiener, William; Naghshineh, Koorosh; Giusti, Ellen

    2005-01-01

    In 2003, Touch Graphics Company carried out research on a new invention that promises to improve accessibility to science museums for visitors who are visually impaired. The system, nicknamed Ping!, allows users to navigate an exhibit area, listen to audio descriptions, and interact with exhibits using a cell phone-based interface. The system…

  17. Millisecond measurements without equipment: time of collision of a ping-pong ball with a table

    NASA Astrophysics Data System (ADS)

    Oladyshkin, Ivan V.; Oladyshkina, Anastasia A.

    2017-01-01

    We describe a simple experiment giving the opportunity to estimate the time of collision of a freely falling ping-pong ball and a table. The method is based on the ball deformation measurement and uses just elementary geometry and kinematics.

  18. The Probing In-Situ With Neutron and Gamma Rays (PING) Instrument for Planetary Composition Measurements

    NASA Technical Reports Server (NTRS)

    Parsons, A.; Bodnarik, J.; Evans, L.; McClanahan, T.; Namkung, M.; Nowicki, S.; Schweitzer, J.; Starr, R.

    2012-01-01

    The Probing In situ with Neutrons and Gamma rays (PING) instrument (formerly named PNG-GRAND) [I] experiment is an innovative application of the active neutron-gamma ray technology successfully used in oil field well logging and mineral exploration on Earth over many decades. The objective of our active neutron-gamma ray technology program at NASA Goddard Space Flight Center (NASA/GSFC) is to bring PING to the point where it can be flown on a variety of surface lander or rover missions to the Moon, Mars, Venus, asteroids, comets and the satellites of the outer planets and measure their bulk surface and subsurface elemental composition without the need to drill into the surface. Gamma-Ray Spectrometers (GRS) have been incorporated into numerous orbital planetary science missions. While orbital measurements can map a planet, they have low spatial and elemental sensitivity due to the low surface gamma ray emission rates reSUlting from using cosmic rays as an excitation source, PING overcomes this limitation in situ by incorporating a powerful neutron excitation source that permits significantly higher elemental sensitivity elemental composition measurements. PING combines a 14 MeV deuterium-tritium Pulsed Neutron Generator (PNG) with a gamma ray spectrometer and two neutron detectors to produce a landed instrument that can determine the elemental composition of a planet down to 30 - 50 cm below the planet's surface, The penetrating nature of .5 - 10 MeV gamma rays and 14 MeV neutrons allows such sub-surface composition measurements to be made without the need to drill into or otherwise disturb the planetary surface, thus greatly simplifying the lander design, We are cun'ently testing a PING prototype at a unique outdoor neutron instrumentation test facility at NASA/GSFC that provides two large (1.8 m x 1.8 m x ,9 m) granite and basalt test formations placed outdoors in an empty field, Since an independent trace elemental analysis has been performed on both these

  19. Modeled Martian subsurface elemental composition measurements with the probing in situ with neutrons and gamma-ray (PING) instrument

    SciTech Connect

    Nowicki, Suzanne F.; Evans, Larry G.; Starr, Richard D.; Schweitzer, Jeffrey S.; Karunatillake, Suniti; McClanahan, Timothy P.; Moersch, Jeffrey E.; Parsons, Ann M.; Tate, Christopher G.

    2016-11-24

    Here, the Probing In situ with Neutrons and Gamma rays (PING) instrument is an innovative application of active neutron-induced gamma-ray technology. The objective of PING is to measure the elemental composition of the Martian regolith. As part 2 of a two-part submission, this manuscript presents PING's sensitivities as a function of the Martian regolith depth and PING's uncertainties in the measurements as a function of observation time in passive and active mode. Part 1 of our submission models the associated regolith types. The modeled sensitivities show that in PING's active mode, where both a Pulsed Neutron Generator (PNG) and a Gamma-Ray Spectrometer (GRS) are used, PING can interrogate the material below the rover to about 20 cm due to the penetrating nature of the high-energy neutrons and the resulting secondary gamma rays observed with the GRS. PING is capable of identifying most major and minor rock-forming elements, including H, O, Na, Mn, Mg, Al, Si, P, S, Cl, Cr, K, Ca, Ti, Fe and Th. The modeled uncertainties show that PING's use of a PNG reduces the required observation times by an order of magnitude over a passive operating mode where the PNG is turned off. While the active mode allows for more complete elemental inventories with higher sensitivity, the gamma-ray signatures of some elements are strong enough to detect in passive mode. We show that PING can detect changes in key marker elements and make thermal neutron measurements in about 1 minute that are sensitive to H and Cl.

  20. Modeled Martian subsurface elemental composition measurements with the probing in situ with neutrons and gamma-ray (PING) instrument

    DOE PAGES

    Nowicki, Suzanne F.; Evans, Larry G.; Starr, Richard D.; ...

    2016-11-24

    Here, the Probing In situ with Neutrons and Gamma rays (PING) instrument is an innovative application of active neutron-induced gamma-ray technology. The objective of PING is to measure the elemental composition of the Martian regolith. As part 2 of a two-part submission, this manuscript presents PING's sensitivities as a function of the Martian regolith depth and PING's uncertainties in the measurements as a function of observation time in passive and active mode. Part 1 of our submission models the associated regolith types. The modeled sensitivities show that in PING's active mode, where both a Pulsed Neutron Generator (PNG) and amore » Gamma-Ray Spectrometer (GRS) are used, PING can interrogate the material below the rover to about 20 cm due to the penetrating nature of the high-energy neutrons and the resulting secondary gamma rays observed with the GRS. PING is capable of identifying most major and minor rock-forming elements, including H, O, Na, Mn, Mg, Al, Si, P, S, Cl, Cr, K, Ca, Ti, Fe and Th. The modeled uncertainties show that PING's use of a PNG reduces the required observation times by an order of magnitude over a passive operating mode where the PNG is turned off. While the active mode allows for more complete elemental inventories with higher sensitivity, the gamma-ray signatures of some elements are strong enough to detect in passive mode. We show that PING can detect changes in key marker elements and make thermal neutron measurements in about 1 minute that are sensitive to H and Cl.« less

  1. [An exploration of the training of medical talents in China for Ryukyu islands based on the Liu qiu bai wen (One Hundred Question of Ryukyu)].

    PubMed

    He, Lanping

    2014-09-01

    Ryukyu sent more than 20 batches of returned students to China for studying during the Ming and Qing Dynasties, many of whom were studying medicine. Liu qiu bai wen (One Hundred Question of Ryukyu) was the record of discussion between Cao Cunxin, a famous doctor of the Qing Dynasty, and the oversea disciples of Lü Fengyi from Ryukyu. However, it was not only a medical book, but also served as an important witness on overseas dissemination of TCM, and the fresh case of Chinese training medical talented persons for Ryukyu. Training Ryukyu medical students in the Qing Dynasty was good for the expansion of Chinese medicine in the Ryukyu, and promoted the development and social progress of the Ryukyu medicine and health, made a significant contribution to maintain the friendly relationship between the two countries.

  2. Loss of l(3)mbt leads to acquisition of the ping-pong cycle in Drosophila ovarian somatic cells.

    PubMed

    Sumiyoshi, Tetsutaro; Sato, Kaoru; Yamamoto, Hitomi; Iwasaki, Yuka W; Siomi, Haruhiko; Siomi, Mikiko C

    2016-07-15

    In Drosophila germ cells, PIWI-interacting RNAs (piRNAs) are amplified through a PIWI slicer-dependent feed-forward loop termed the ping-pong cycle, yielding secondary piRNAs. However, the detailed mechanism remains poorly understood, largely because an ex vivo model system amenable to biochemical analyses has not been available. Here, we show that CRISPR-mediated loss of function of lethal (3) malignant brain tumor [l(3)mbt] leads to ectopic activation of the germ-specific ping-pong cycle in ovarian somatic cells. Perinuclear foci resembling nuage, the ping-pong center, appeared following l(3)mbt mutation. This activation of the ping-pong machinery in cultured cells will greatly facilitate elucidation of the mechanism underlying secondary piRNA biogenesis in Drosophila. © 2016 Sumiyoshi et al.; Published by Cold Spring Harbor Laboratory Press.

  3. Loss of l(3)mbt leads to acquisition of the ping-pong cycle in Drosophila ovarian somatic cells

    PubMed Central

    Sumiyoshi, Tetsutaro; Sato, Kaoru; Yamamoto, Hitomi; Iwasaki, Yuka W.; Siomi, Haruhiko; Siomi, Mikiko C.

    2016-01-01

    In Drosophila germ cells, PIWI-interacting RNAs (piRNAs) are amplified through a PIWI slicer-dependent feed-forward loop termed the ping-pong cycle, yielding secondary piRNAs. However, the detailed mechanism remains poorly understood, largely because an ex vivo model system amenable to biochemical analyses has not been available. Here, we show that CRISPR-mediated loss of function of lethal (3) malignant brain tumor [l(3)mbt] leads to ectopic activation of the germ-specific ping-pong cycle in ovarian somatic cells. Perinuclear foci resembling nuage, the ping-pong center, appeared following l(3)mbt mutation. This activation of the ping-pong machinery in cultured cells will greatly facilitate elucidation of the mechanism underlying secondary piRNA biogenesis in Drosophila. PMID:27474440

  4. PING 2.0: an R/Bioconductor package for nucleosome positioning using next-generation sequencing data.

    PubMed

    Woo, Sangsoon; Zhang, Xuekui; Sauteraud, Renan; Robert, François; Gottardo, Raphael

    2013-08-15

    MNase-Seq and ChIP-Seq have evolved as popular techniques to study chromatin and histone modification. Although many tools have been developed to identify enriched regions, software tools for nucleosome positioning are still limited. We introduce a flexible and powerful open-source R package, PING 2.0, for nucleosome positioning using MNase-Seq data or MNase- or sonicated- ChIP-Seq data combined with either single-end or paired-end sequencing. PING uses a model-based approach, which enables nucleosome predictions even in the presence of low read counts. We illustrate PING using two paired-end datasets from Saccharomyces cerevisiae and compare its performance with nucleR and ChIPseqR. PING 2.0 is available from the Bioconductor website at http://bioconductor.org. It can run on Linux, Mac and Windows.

  5. Ping-pong gaze” secondary to monoamine oxidase inhibitor overdose

    PubMed Central

    Attaway, Amy; Sroujieh, Laila; Mersfelder, Tracey L.; Butler, Christopher; Ouellette, Daniel

    2016-01-01

    An infrequent manifestation of monoamine oxidase inhibitor (MAOI) toxicity is “ping-pong gaze” (PPG). We describe the case of a 26-year-old female who was found unresponsive after taking 40 tablets of phenelzine. On presentation to the hospital, her eyes were moving in characteristic “ping pong” fashion. After 6 hours her gaze terminated. The following day her neurologic exam was benign and she had no long-term sequelae. While the etiology of PPG is unknown, it is most often seen with irreversible structural brain damage. However, a detailed literature review revealed that previous cases of MAOI toxicity where the patient survived have all had complete neurologic recovery. PMID:27127395

  6. Planetary Geochemistry Techniques: Probing In-Situ with Neutron and Gamma Rays (PING) Instrument

    NASA Technical Reports Server (NTRS)

    Parsons, A.; Bodnarik, J.; Burger, D.; Evans, L.; Floyd, S.; Lin, L.; McClanahan, T.; Nankung, M.; Nowicki, S.; Schweitzer, J.; Starr, R.; Trombka, J.

    2011-01-01

    The Probing In situ with Neutrons and Gamma rays (PING) instrument is a promising planetary science application of the active neutron-gamma ray technology so successfully used in oil field well logging and mineral exploration on Earth. The objective of our technology development program at NASA Goddard Space Flight Center's (NASA/GSFC) Astrochemistry Laboratory is to extend the application of neutron interrogation techniques to landed in situ planetary composition measurements by using a 14 MeV Pulsed Neutron Generator (PNG) combined with neutron and gamma ray detectors, to probe the surface and subsurface of planetary bodies without the need to drill. We are thus working to bring the PING instrument to the point where it can be flown on a variety of surface lander or rover missions to the Moon, Mars, Venus, asteroids, comets and the satellites of the outer planets.

  7. The rice miniature inverted repeat transposable element mPing is an effective insertional mutagen in soybean.

    PubMed

    Hancock, C Nathan; Zhang, Feng; Floyd, Kristen; Richardson, Aaron O; Lafayette, Peter; Tucker, Donna; Wessler, Susan R; Parrott, Wayne A

    2011-10-01

    Insertional mutagenesis of legume genomes such as soybean (Glycine max) should aid in identifying genes responsible for key traits such as nitrogen fixation and seed quality. The relatively low throughput of soybean transformation necessitates the use of a transposon-tagging strategy where a single transformation event will produce many mutations over a number of generations. However, existing transposon-tagging tools being used in legumes are of limited utility because of restricted transposition (Ac/Ds: soybean) or the requirement for tissue culture activation (Tnt1: Medicago truncatula). A recently discovered transposable element from rice (Oryza sativa), mPing, and the genes required for its mobilization, were transferred to soybean to determine if it will be an improvement over the other available transposon-tagging tools. Stable transformation events in soybean were tested for mPing transposition. Analysis of mPing excision at early and late embryo developmental stages revealed increased excision during late development in most transgenic lines, suggesting that transposition is developmentally regulated. Transgenic lines that produced heritable mPing insertions were identified, with the plants from the highest activity line producing at least one new insertion per generation. Analysis of the mPing insertion sites in the soybean genome revealed that features displayed in rice were retained including transposition to unlinked sites and a preference for insertion within 2.5 kb of a gene. Taken together these findings indicate that mPing has the characteristics necessary for an effective transposon-tagging resource.

  8. Predictive analysis of landslide susceptibility in the Kao-Ping watershed, Taiwan under climate change conditions

    NASA Astrophysics Data System (ADS)

    Shou, K. J.; Wu, C. C.; Lin, J. F.

    2015-01-01

    Among the most critical issues, climatic abnormalities caused by global warming also affect Taiwan significantly for the past decade. The increasing frequency of extreme rainfall events, in which concentrated and intensive rainfalls generally cause geohazards including landslides and debris flows. The extraordinary Typhoon Morakot hit Southern Taiwan on 8 August 2009 and induced serious flooding and landslides. In this study, the Kao-Ping River watershed was adopted as the study area, and the typical events 2007 Krosa Typhoon and 2009 Morakot Typhoon were adopted to train the susceptibility model. This study employs rainfall frequency analysis together with the atmospheric general circulation model (AGCM) downscaling estimation to understand the temporal rainfall trends, distributions, and intensities in the Kao-Ping River watershed. The rainfall estimates were introduced in the landslide susceptibility model to produce the predictive landslide susceptibility for various rainfall scenarios, including abnormal climate conditions. These results can be used for hazard remediation, mitigation, and prevention plans for the Kao-Ping River watershed.

  9. PING Gamma Ray and Neutron Measurements of a Meter-Sized Carbonaceous Asteroid Analog

    NASA Technical Reports Server (NTRS)

    Bodnarik, J.; Burger, D.; Evans, L.; Floyd, S.; Lim, L.; McClanahan, T.; Namkung, M.; Nowicki, S.; Parsons, A.; Schweitzer, J.; Starr, R.; Trombka, J.

    2011-01-01

    Determining the elemental composition of carbonaceous (spectral type C) asteroids is still one of the basic problems when studying these objects. The only main source of elemental composition information for asteroids is from their optical, NIR and IR properties, which include their spectral reflectance characteristics, albedo, polarization, and the comparison of optical spectroscopy with meteorite groups corresponding to asteroids of every spectral type. Unfortunately, these sources reflect observations from widely contrasting spatial scales that presently yield a void in the continuum of microscopic and macroscopic evidence, a lack of in situ measurement confirmation, and require deeper sensing techniques to discern the nature of these asteroids. The Probing In situ with Neutrons and Gamma rays (PING) instrument is ideally suited to address this problem because it can be used to determine the bulk elemental composition, H and C content, the average atomic weight and density of the surface and subsurface layers of C-type asteroids, and can provide measurements used to determine the difference between and distinguish between different types of asteroids. We are currently developing the PING instrument that combines gamma ray and neutron detectors with a 14 Me V pulsed neutron generator to determine the in-situ bulk elemental abundances and geochemistry of C-type asteroids with a spatial resolution of 1 m down to depths of tens of cm to 1 m. One aspect of the current work includes experimentally testing and optimizing PING on a known meter-sized Columbia River basalt C-type asteroid analog sample that has a similar composition and the same neutron response as that of a C-type asteroid. An important part of this effort focuses on utilizing timing measurements to isolate gamma rays produced by neutron inelastic scattering, neutron capture and delayed activation processes. Separating the gamma ray spectra by nuclear processes results in higher precision and sensitivity

  10. New constraints on the Mae Ping core-complex NW-Thailand: Is the Mae-Ping an Indosinian (Triassic) relict?

    NASA Astrophysics Data System (ADS)

    Palzer, Markus; Oesterle, Juergen; Kloetzli, Urs

    2013-04-01

    The Mae Ping fault zone is seen as one of the major strike-slip shear zones in SE-Asia and is trending NW-SE over 500 km across Thailand. Within this fault zone, a 150 km long and 5 km wide core-complex of ductile deformed amphibolite-facies rocks containing lenses of an older high-grade px-amph-pl paragenesis occurs. These so called Lan Sang Gneisses are named after the outcrops situated in the Lan Sang National Park. Despite several former investigations (Lacassin et al., 1997; Morley et al., 2012) some aspects concerning the time, regime and cause of exhumation remain unclear. Further on, the old relictic granulite-facies paragenesis has never been studied in detail. Older models constitute a restraining bend within a left-lateral regime as the origin of the exhumation of the Lan Sang Gneisses. New detailed structural, petrographical and geochronological investigations of the Lan Sang Gneisses were undertaken to develop different PTt-paths for different rock types within the Lan Sang Gneisses with special emphasis on the lenses of old high grade rocks which probably represent an older lower crust. We use detailed field investigations on a NE-SW profile following a river outcrop in Lan Sang National Park, zircon and monazite ages of three different rock types, structural and petrographical investigations on more than 100 thin sections and electron microprobe analyses and techniques such as geothermometers and -barometers. On the basis of our observations and measurements, we are able to reconstruct and quantify the different prograde and retrograde histories. First results now strongly question the model of a restraining bend and lead us to the conclusion that the origin of the amphibolite-facies deformation may lie in the late Triassic Indosinian orogeny. If this is the case, the importance of the whole Mae-Ping for the lateral Extrusion of SE-Asia during the Himalayan orogeny must be questioned.

  11. Solar X-ray polarimetry and spectrometry instrument PING-M for the Interhelioprobe mission

    NASA Astrophysics Data System (ADS)

    Kotov, Yu. D.; Yurov, V. N.; Glyanenko, A. S.; Lupar, E. E.; Kochemasov, A. V.; Trofimov, Yu. A.; Zakharov, M. S.; Faradzhaev, R. M.; Tyshkevich, V. G.; Rubtsov, I. V.; Dergachev, V. A.; Kruglov, E. M.; Lazutkov, V. P.; Savchenko, M. I.; Skorodumov, D. V.

    2016-08-01

    The PING-M experiment is designed to investigate solar X-ray activity. The instrument includes a hard X-ray polarimeter (PING-P), a hard X-ray spectrometer (HXRS) and a soft X-ray spectrometer (SXRS). PING-P has the energy range of 20-150 keV and an effective area of about 2.5 cm2. It uses three organic scintillation detectors as active scatterers, which work in coincidence with six absorber detectors, based on CsI(Tl) scintillator. This technique allows us to considerably improve the polarimeter sensitivity. HXRS has the energy range of 20-600 keV and an effective area of about 15 cm2. It is based on a fast inorganic scintillator (LaBr3(Ce) or CeBr3) with a relatively high energy resolution of 3.5-4.5% at 662 keV. The SXRS energy range is 1.5-25 keV, and its aperture is ø0.1 mm, which provides the registration of solar flares in the range from C1 to X20 class of GOES scale. It is based on a SDD semiconductor detector with an energy resolution better than 200 eV at 5.9 keV line. The experiment will be performed onboard the Russian interplanetary mission Interhelioprobe which is planned for launch after 2025. The instrument will allow us to investigate angular and energy distributions of accelerated electrons, plasma heating processes, etc. Stereoscopic polarimetry and spectrometric observations will be possible if a similar instrument is installed onboard a near Earth satellite, or the second probe of the Interhelioprobe mission.

  12. Solar X-Ray Spectroscopy And Polarimetry By Instrument Ping-M Onboard Interhelioprobe

    NASA Astrophysics Data System (ADS)

    Kotov, Yury; Dergachev, Valentin; Kochemasov, Alexey; Yurov, Vitaly; Tyshkevich, V.; Glyanenko, Alexander; Savchenko, Mikhail; Lazutkov, Vadim; Skorodumov, Dmitry; Trofimov, Yury; Zakharov, Mikhail; Rubtsov, Igor; Kruglov, Evgeniy

    The instrument PING-M for X-ray spectroscopy and polarimetry of solar full disk radiation is described. It will be the part of scientific instrument set for the InterHelioProbe space mission. Instrument consists of three detectors: the Soft X-ray detector (SXRD), the Hard X-ray detector (HXRD) and Hard X-ray polarimeter (PING-P). Spectrometer SXRD is based on a relatively novel type of semiconductor detector SDD (Silicon Drift Detector) that will operate in the energy range 1.5-25 keV, which is similar to GOES X-Ray Sensor (XRS) region. Unlike GOES the SXRD is capable to measure the energy of each photon with high resolution (better 200 eV at 5.9 keV) and operate with high count rate. The X-ray spectra of solar flares obtained by the SXRD should show evidence of Fe and Fe/Ni line emission and multi-thermal plasma. HXRD operates in energy range 15-150 keV. Fast nonorganic scintillator (is based on LaBr3(Ce)) with good energy resolution (≤12% at 60keV and ≤3.5% at 662keV) is used. Apart from measurement of spectra the value of the break energy point that separates the thermal and non-thermal processes in flare would be revealed. In the talk the results of testing of laboratory models are presented. PING-P Hard X-ray polarimeter consists of active scatterer made of three organic p-terphenyl scintillators and six peripheral scattered radiation detectors made of CsI(Tl) scintillators. Effective area of polarimeter is about 5 cm2 in its energy range. Minimal measurable degree of polarization is 0.9 % for 100 sec exposition and X1 solar flare.

  13. [Experimental study of the virus inhibitory effect of chuan-kang-ping granule].

    PubMed

    Li, Z; Dong, G; Li, Z

    2001-03-01

    To explore the virus inhibitory effect of Chuan-Kang-Ping Granule. Using tissue culture technique, the maximal non-toxic concentration of the drugs in Hep-2 cell culture were measured and the virus inhibitory index of the drugs on the respiratory syncytial virus (RSV), the coxackie B3 virus (Cox B3) and the influenza A1 virus (A1) was calculated. In addition, the degrees of inhibition of the drugs on the cytopathic effect of viruses in cell culture was observed by changing sequence of adding the viruses and the drugs. The maximal non-toxic concentration of Chuan-Kang-Ping Granule was 1:16. The virus inhibitory index on RSV, CoxB3, A1 was 8.8 and 2, respectively. The maximal non-toxic concentration of Shuang-Huang-Lian oral administration Liquid was 1:32. The virus inhibitory index on RSV, CoxB3, A1 was 8, 16 and 2, respectively. The degrees of cytopathic effect were different when changing sequence of adding the viruses and the drugs. Chuan-Kang-Ping Granule inhibited the replication of RSV, CoxB3, A1 in cultured cells. The inhibitory effect of the drugs were the same or nearly the same with Shuang-Huang-Lian oral administration liquid. The mechanism of the inhibitory effects of the drugs on the viruses was probably the direct killing effect in vitro, or the drugs might inhibit some key link of the replication of the viruses in cultured cells.

  14. Precise repair of mPing excision sites is facilitated by target site duplication derived microhomology.

    PubMed

    Gilbert, David M; Bridges, M Catherine; Strother, Ashley E; Burckhalter, Courtney E; Burnette, James M; Hancock, C Nathan

    2015-01-01

    A key difference between the Tourist and Stowaway families of miniature inverted repeat transposable elements (MITEs) is the manner in which their excision alters the genome. Upon excision, Stowaway-like MITEs and the associated Mariner elements usually leave behind a small duplication and short sequences from the end of the element. These small insertions or deletions known as "footprints" can potentially disrupt coding or regulatory sequences. In contrast, Tourist-like MITEs and the associated PIF/Pong/Harbinger elements generally excise precisely, returning the genome to its original state. The purpose of this study was to determine the mechanisms underlying these excision differences, including the role of the host DNA repair mechanisms. The transposition of the Tourist-like element, mPing, and the Stowaway-like element, 14T32, were evaluated using yeast transposition assays. Assays performed in yeast strains lacking non-homologous end joining (NHEJ) enzymes indicated that the excision sites of both elements were primarily repaired by NHEJ. Altering the target site duplication (TSD) sequences that flank these elements reduced the transposition frequency. Using yeast strains with the ability to repair the excision site by homologous repair showed that some TSD changes disrupt excision of the element. Changing the ends of mPing to produce non-matching TSDs drastically reduced repair of the excision site and resulted in increased generation of footprints. Together these results indicate that the difference in Tourist and Stowaway excision sites results from transposition mechanism characteristics. The TSDs of both elements play a role in element excision, but only the mPing TSDs actively participate in excision site repair. Our data suggests that Tourist-like elements excise with staggered cleavage of the TSDs, which provides microhomology that facilitates precise repair. This slight modification in the transposition mechanism results in more efficient repair of

  15. Development of the Probing In-Situ with Neutron and Gamma Rays (PING) Instrument for Planetary Science Applications

    NASA Technical Reports Server (NTRS)

    Parsons, A.; Bodnarik, J.; Burger, D.; Evans, L.; Floyd, S; Lim, L.; McClanahan, T.; Namkung, M.; Nowicki, S.; Schweitzer, J.; Starr, R.; Trombka, J.

    2011-01-01

    The Probing In situ with Neutrons and Gamma rays (PING) instrument is a promising planetary science application of the active neutron-gamma ray technology that has been used successfully in oil field well logging and mineral exploration on Earth for decades. Similar techniques can be very powerful for non-invasive in situ measurements of the subsurface elemental composition on other planets. The objective of our active neutron-gamma ray technology program at NASA Goddard Space Flight Center (NASA/GSFC) is to bring instruments using this technology to the point where they can be flown on a variety of surface lander or rover missions to the Moon, Mars, Venus, asteroids, comets and the satellites of the outer planets. PING combines a 14 MeV deuterium-tritium pulsed neutron generator with a gamma ray spectrometer and two neutron detectors to produce a landed instrument that can determine the elemental composition of a planet down to 30 - 50 cm below the planet's surface. The penetrating nature of.5 - 10 MeV gamma rays and 14 MeV neutrons allows such sub-surface composition measurements to be made without the need to drill into or otherwise disturb the planetary surface, thus greatly simplifying the lander design. We are currently testing a PING prototype at a unique outdoor neutron instrumentation test facility at NASA/GSFC that provides two large (1.8 m x 1.8 m x.9 m) granite and basalt test formations placed outdoors in an empty field. Since an independent trace elemental analysis has been performed on both the Columbia River basalt and Concord Gray granite materials, these samples present two known standards with which to compare PING's experimentally measured elemental composition results. We will present experimental results from PING measurements of both the granite and basalt test formations and show how and why the optimum PING instrument operating parameters differ for studying the two materials.

  16. Security analysis of the “Ping-Pong” quantum communication protocol in the presence of collective-rotation noise

    NASA Astrophysics Data System (ADS)

    Li, Jian; Li, Lingyun; Jin, Haifei; Li, Ruifan

    2013-11-01

    Environmental noise is inevitable in non-isolated systems. It is, therefore, necessary to analyze the security of the “Ping-Pong” protocol in a noisy environment. An excellent model for collective-rotation noise is introduced, and information theoretical methods are applied to analyze the security of this protocol. If noise level ε is lower than 11%, an eavesdropper can gain some, but not all, information freely without being detected. Otherwise, the protocol becomes insecure. We conclude that the use of ‘Ping-Pong’ protocol as a quantum secure direct communication (QSDC) protocol is quasi-secure, as declared by the original author when ε⩽11%.

  17. Synthesis and Electrochemical Properties Characterization of SnO2-coated LiNi1/3Co1/3Mn1/3O2 Cathode Material for Lithium Ion Batteries

    DTIC Science & Technology

    2009-01-01

    Synthesis and electrochemical properties characterization of SnO2 -coated LiNi1/3Co1/3Mn1/3O2 cathode material for lithium ion batteries Ping Yang...China Key words: Li-ion battery; cathode materials; LiNi1/3Co1/3Mn1/3O2; heterogeneous nucleation; SnO2 -coated; electrochemical performance...Abstract LiNi1/3Co1/3Mn1/3O2 cathode materials have been coated with SnO2 (3% wt) by heterogeneous nucleation process to improve its electrochemical

  18. The Second-phase Development of the China JinPing Underground Laboratory

    NASA Astrophysics Data System (ADS)

    Li, Jianmin; Ji, Xiangdong; Haxton, Wick; Wang, Joseph S. Y.

    During 2013-2015 an expansion of the China JinPing underground Laboratory (CJPL) will be undertaken along a main branch of a bypass tunnel in the JinPing tunnel complex. This second phase of CJPL will increase laboratory space to approximately 96,000 m3, which can be compared to the existing CJPL-I volume of ∼ 4,000 m3. One design configuration has eight additional hall spaces, each over 60 m long and approximately12 m in width, with overburdens of about 2.4 km of rock, oriented parallel to and away from the main water transport and auto traffic tunnels. There are additional possibilities for further expansions at a nearby second bypass tunnel and along the entrance and exit branches of both bypass tunnels, potentially leading to an expanded CJPL comparable in size to Gran Sasso. Concurrent with the excavation activities, planning is underway for dark matter and other rare-event detectors, as well as for geophysics/engineering and other coupled multi-disciplinary sensors. In the town meeting on 8 September, 2013 at Asilomar, CA, associated with the 13th International Conference on Topics in Astroparticle and Underground Physics (TAUP), presentations and panel discussions addressed plans for one-ton expansions of the current CJPL germanium detector array of the China Darkmatter EXperiment (CDEX) collaboration and of the duel-phase xenon detector of the Panda-X collaboration, as well as possible new detector initiatives for dark matter studies, low-energy solar neutrino detection, neutrinoless double beta searches, and geoneutrinos. JinPing was also discussed as a site for a low-energy nuclear astrophysics accelerator. Geophysics/engineering opportunities include acoustic and micro-seismic monitoring of rock bursts during and after excavation, coupled-process in situ measurements, local, regional, and global monitoring of seismically induced radon emission, and electromagnetic signals. Additional ideas and projects will likely be developed in the next few years

  19. The second-phase development of the China JinPing underground laboratory

    SciTech Connect

    Li, Jianmin; Ji, Xiangdong; Haxton, Wick; Wang, Joseph S.Y.

    2015-03-24

    During 2013-2015 an expansion of the China JinPing underground Laboratory (CJPL) will be undertaken along a main branch of a bypass tunnel in the JinPing tunnel complex. This second phase of CJPL will increase laboratory space to approximately 96,000 m³, which can be compared to the existing CJPL-I volume of ~ 4,000 m³. One design configuration has eight additional hall spaces, each over 60 m long and approximately 12 m in width, with overburdens of about 2.4 km of rock, oriented parallel to and away from the main water transport and auto traffic tunnels. There are additional possibilities for further expansions at a nearby second bypass tunnel and along the entrance and exit branches of both bypass tunnels, potentially leading to an expanded CJPL comparable in size to Gran Sasso. Concurrent with the excavation activities, planning is underway for dark matter and other rare-event detectors, as well as for geophysics/engineering and other coupled multi-disciplinary sensors. In the town meeting on 8 September, 2013 at Asilomar, CA, associated with the 13th International Conference on Topics in Astroparticle and Underground Physics (TAUP), presentations and panel discussions addressed plans for one-ton expansions of the current CJPL germanium detector array of the China Darkmatter EXperiment (CDEX) collaboration and of the duel-phase xenon detector of the Panda-X collaboration, as well as possible new detector initiatives for dark matter studies, low-energy solar neutrino detection, neutrinoless double beta searches, and geoneutrinos. JinPing was also discussed as a site for a low-energy nuclear astrophysics accelerator. Geophysics/engineering opportunities include acoustic and micro-seismic monitoring of rock bursts during and after excavation, coupled-process in situ measurements, local, regional, and global monitoring of seismically induced radon emission, and electromagnetic signals. Additional ideas and projects will likely be developed in the

  20. The second-phase development of the China JinPing underground laboratory

    DOE PAGES

    Li, Jianmin; Ji, Xiangdong; Haxton, Wick; ...

    2015-03-24

    During 2013-2015 an expansion of the China JinPing underground Laboratory (CJPL) will be undertaken along a main branch of a bypass tunnel in the JinPing tunnel complex. This second phase of CJPL will increase laboratory space to approximately 96,000 m³, which can be compared to the existing CJPL-I volume of ~ 4,000 m³. One design configuration has eight additional hall spaces, each over 60 m long and approximately 12 m in width, with overburdens of about 2.4 km of rock, oriented parallel to and away from the main water transport and auto traffic tunnels. There are additional possibilities for furthermore » expansions at a nearby second bypass tunnel and along the entrance and exit branches of both bypass tunnels, potentially leading to an expanded CJPL comparable in size to Gran Sasso. Concurrent with the excavation activities, planning is underway for dark matter and other rare-event detectors, as well as for geophysics/engineering and other coupled multi-disciplinary sensors. In the town meeting on 8 September, 2013 at Asilomar, CA, associated with the 13th International Conference on Topics in Astroparticle and Underground Physics (TAUP), presentations and panel discussions addressed plans for one-ton expansions of the current CJPL germanium detector array of the China Darkmatter EXperiment (CDEX) collaboration and of the duel-phase xenon detector of the Panda-X collaboration, as well as possible new detector initiatives for dark matter studies, low-energy solar neutrino detection, neutrinoless double beta searches, and geoneutrinos. JinPing was also discussed as a site for a low-energy nuclear astrophysics accelerator. Geophysics/engineering opportunities include acoustic and micro-seismic monitoring of rock bursts during and after excavation, coupled-process in situ measurements, local, regional, and global monitoring of seismically induced radon emission, and electromagnetic signals. Additional ideas and projects will likely be developed in the next few

  1. The ping-pong cannon demonstration: Optical studies and numerical simulation

    NASA Astrophysics Data System (ADS)

    Peterson, Richard; Stein, Keith

    2005-09-01

    This presentation describes the use of laser pulse photography, optical timing, pulsed Schlieren, and heterodyne interferometry to look more closely at the fluid dynamics of a recently popular lecture demonstration-the so-called ``ping-pong cannon.'' Optical diagnostic techniques have been applied to two types of these cannons, and led to greater knowledge of the kinematics of the accelerating ball, along with some insight into the exit mechanism and subsequent target interactions. Also will be described how a 1D numerical simulation allows visualization of shock wave formation within the tube during ball acceleration. Solutions of the Euler equation are obtained using the method of space-time finite elements, while the ball is tracked as an interface in the compressible fluid mesh. [Work supported in part by the MN NASA Space Grant and the Carlsen-Lewis Endowment of Bethel University.

  2. Beam pinging, sweeping, shaking, and electron/ion collecting, at the Proton Storage Ring

    SciTech Connect

    Hardek, T.W.; Macek, R.J.; Plum, M.A.; Wang, T.S.F.

    1993-06-01

    We have built, installed and tested a pinger for use as a general diagnostic at the Los Alamos Proton Storage Ring (PSR). Two 4-m-long parallel-plate electrodes with a plate spacing of 10.2 cm provide kicks of up to 1.1 mrad. A pair of solid-state pulsers may be operated in a single-pulse mode for beam pinging (tune measurements) or in a burst mode at up to 700 kHz pulse rates for beam sweeping. During our 1992 operating period we used the pinger for beam sweeping, for beam shaking, for measuring the tune shift, and we have used it as an ion chamber. Using the pinger as an ion chamber during production conditions has yielded some surprising results.

  3. Beam pinging, sweeping, shaking, and electron/ion collecting, at the Proton Storage Ring

    SciTech Connect

    Hardek, T.W.; Macek, R.J.; Plum, M.A.; Wang, T.S.F.

    1993-01-01

    We have built, installed and tested a pinger for use as a general diagnostic at the Los Alamos Proton Storage Ring (PSR). Two 4-m-long parallel-plate electrodes with a plate spacing of 10.2 cm provide kicks of up to 1.1 mrad. A pair of solid-state pulsers may be operated in a single-pulse mode for beam pinging (tune measurements) or in a burst mode at up to 700 kHz pulse rates for beam sweeping. During our 1992 operating period we used the pinger for beam sweeping, for beam shaking, for measuring the tune shift, and we have used it as an ion chamber. Using the pinger as an ion chamber during production conditions has yielded some surprising results.

  4. Security of modified Ping-Pong protocol in noisy and lossy channel

    PubMed Central

    Han, Yun-Guang; Yin, Zhen-Qiang; Li, Hong-Wei; Chen, Wei; Wang, Shuang; Guo, Guang-Can; Han, Zheng-Fu

    2014-01-01

    The “Ping-Pong” (PP) protocol is a two-way quantum key protocol based on entanglement. In this protocol, Bob prepares one maximally entangled pair of qubits, and sends one qubit to Alice. Then, Alice performs some necessary operations on this qubit and sends it back to Bob. Although this protocol was proposed in 2002, its security in the noisy and lossy channel has not been proven. In this report, we add a simple and experimentally feasible modification to the original PP protocol, and prove the security of this modified PP protocol against collective attacks when the noisy and lossy channel is taken into account. Simulation results show that our protocol is practical. PMID:24816899

  5. Measurement of cosmic ray flux in the China JinPing underground laboratory

    NASA Astrophysics Data System (ADS)

    Wu, Yu-Cheng; Hao, Xi-Qing; Yue, Qian; Li, Yuan-Jing; Cheng, Jian-Ping; Kang, Ke-Jun; Chen, Yun-Hua; Li, Jin; Li, Jian-Min; Li, Yu-Lan; Liu, Shu-Kui; Ma, Hao; Ren, Jin-Bao; Shen, Man-Bin; Wang, Ji-Min; Wu, Shi-Yong; Xue, Tao; Yi, Nan; Zeng, Xiong-Hui; Zeng, Zhi; Zhu, Zhong-Hua

    2013-08-01

    The China JinPing underground Laboratory (CJPL) is the deepest underground laboratory running in the world at present. In such a deep underground laboratory, the cosmic ray flux is a very important and necessary parameter for rare-event experiments. A plastic scintillator telescope system has been set up to measure the cosmic ray flux. The performance of the telescope system has been studied using the cosmic rays on the ground laboratory near the CJPL. Based on the underground experimental data taken from November 2010 to December 2011 in the CJPL, which has an effective live time of 171 days, the cosmic ray muon flux in the CJPL is measured to be (2.0±0.4)×10-10/(cm2·s). The ultra-low cosmic ray background guarantees an ideal environment for dark matter experiments at the CJPL.

  6. Creating accessible science museums with user-activated environmental audio beacons (ping!).

    PubMed

    Landau, Steven; Wiener, William; Naghshineh, Koorosh; Giusti, Ellen

    2005-01-01

    In 2003, Touch Graphics Company carried out research on a new invention that promises to improve accessibility to science museums for visitors who are visually impaired. The system, nicknamed Ping!, allows users to navigate an exhibit area, listen to audio descriptions, and interact with exhibits using a cell phone-based interface. The system relies on computer telephony, and it incorporates a network of wireless environmental audio beacons that can be triggered by users wishing to travel to destinations they choose. User testing indicates that the system is effective, both as a way-finding tool and as a means of providing accessible information on museum content. Follow-up development projects will determine if this approach can be successfully implemented in other settings and for other user populations.

  7. A student's analysis of the Moi University-Linköping University exchange programme.

    PubMed

    Mwenda, A S

    2012-11-01

    Introduction : Moi University College of Health Sciences was established in 1989. It is comprised of the schools of medicine, nursing, public health and dentistry. Since its inception, the college has been in collaboration with Linköping University in Sweden. This collaboration has taken the form of student and staff exchanges, as well as infrastructure and library improvements. This study was carried out to analyse the exchange programme and highlight some of the strengths that the exchange programme brings to the students' academic experience. Methods : A qualitative cross-sectional survey was conducted among the students who participated in the elective/exchange programme in the years 2009, 2010 and 2011. Self-administered questionnaires were completed by the participants. Additional data were obtained from the recommendations and conclusions from the reports that the students wrote after their participation in the exchange programme. Focus group discussions and key informant interviews were also carried out. Results : A total of 46 students participated in the exchange programme: 27 from Moi University and 19 from Linköping University. The disciplines of students reflected the undergraduate courses offered by these universities. The exchange programme's strengths were exposing students to new cultural settings, different healthcare system organisation and influencing future academic and personal lives, as well as making education global. The main challenge facing the exchange programme was language. Discussion : This study shows the exchange programme as a strong pillar of the medical education curriculum, enabling students to get a global perspective on their education, while exposing them to significant cultural and healthcare organisation diversity. There is a need to expand the collaboration so that more students have the opportunity to experience the overseas exchange programme.

  8. pING family of conjugative plasmids from the extremely thermophilic archaeon Sulfolobus islandicus: insights into recombination and conjugation in Crenarchaeota.

    PubMed

    Stedman, K M; She, Q; Phan, H; Holz, I; Singh, H; Prangishvili, D; Garrett, R; Zillig, W

    2000-12-01

    A novel family of conjugative plasmids from Sulfolobus comprising the active variants pING1, -4, and -6 and the functionally defective variants pING2 and -3, which require the help of an active variant for spreading, has been extensively characterized both functionally and molecularly. In view of the sparse similarity between bacterial and archaeal conjugation and the lack of a practical genetic system for Sulfolobus, we compared the functions and sequences of these variants and the previously described archaeal conjugative plasmid pNOB8 in order to identify open reading frames (ORFs) and DNA sequences that are involved in conjugative transfer and maintenance of these plasmids in Sulfolobus. The variants pING4 and -6 are reproducibly derived from pING1 in vivo by successive transpositions of an element from the Sulfolobus genome. The small defective but mobile variants pING2 and -3, which both lack a cluster of highly conserved ORFs probably involved in plasmid transfer, were shown to be formed in vivo by recombinative deletion of the larger part of the genomes of pING4 and pING6, respectively. The efficient occurrence of these recombination processes is further evidence for the striking plasticity of the Sulfolobus genome.

  9. Kinetics of Spanish broom peroxidase obeys a Ping-Pong Bi-Bi mechanism with competitive inhibition by substrates.

    PubMed

    Pérez Galende, Patricia; Hidalgo Cuadrado, Nazaret; Kostetsky, Eduard Ya; Roig, Manuel G; Villar, Enrique; Shnyrov, Valery L; Kennedy, John F

    2015-11-01

    In plants, adverse conditions often induce an increase in reactive oxygen species (ROS) such as hydrogen peroxide (H2O2). H2O2 is reduced to water, and thus becomes detoxified by enzymes such as Cytisus multiflorus peroxidase (CMP). Here, the steady-state kinetics of the H2O2-supported oxidation of different organic substrates by CMP was investigated. Analysis of the initial rates vs. H2O2 and reducing substrate concentrations proved to be consistent with a substrate-inhibited Ping-Pong Bi-Bi reaction mechanism. The phenomenological approach expresses the peroxidase Ping-Pong mechanism in the form of the Michaelis-Menten equation and affords an interpretation of the effects in terms of the kinetic parameters [Formula: see text] , [Formula: see text] , kcat, [Formula: see text] , [Formula: see text] and of the microscopic rate constants, k1 and k3, of the shared three-step catalytic cycle of peroxidases.

  10. piRNA biogenesis during adult spermatogenesis in mice is independent of the ping-pong mechanism

    PubMed Central

    Beyret, Ergin; Liu, Na; Lin, Haifan

    2012-01-01

    piRNAs, a class of small non-coding RNAs associated with PIWI proteins, have broad functions in germline development, transposon silencing, and epigenetic regulation. In diverse organisms, a subset of piRNAs derived from repeat sequences are produced via the interplay between two PIWI proteins. This mechanism, termed “ping-pong” cycle, operates among the PIWI proteins of the primordial mouse testis; however, its involvement in postnatal testes remains elusive. Here we show that adult testicular piRNAs are produced independent of the ping-pong mechanism. We identified and characterized large populations of piRNAs in the adult and postnatal developing testes associated with MILI and MIWI, the only PIWI proteins detectable in these testes. No interaction between MILI and MIWI or sequence feature for the ping-pong mechanism among their piRNAs was detected in the adult testis. The majority of MILI- and MIWI-associated piRNAs originate from the same DNA strands within the same loci. Both populations of piRNAs are biased for 5′ Uracil but not for Adenine on the 10th nucleotide position, and display no complementarity. Furthermore, in Miwi mutants, MILI-associated piRNAs are not downregulated, but instead upregulated. These results indicate that the adult testicular piRNAs are predominantly, if not exclusively, produced by a primary processing mechanism instead of the ping-pong mechanism. In this primary pathway, biogenesis of MILI- and MIWI-associated piRNAs may compete for the same precursors; the types of piRNAs produced tend to be non-selectively dictated by the available precursors in the cell; and precursors with introns tend to be spliced before processed into piRNAs. PMID:22907665

  11. Innovation in medical education: how Linköping created a Blue Ocean for medical education in Sweden.

    PubMed

    Savage, Carl; Brommels, Mats

    2008-06-01

    The Linköping Health University is an example of a medical school which has succeeded, not only with a major curricular change, transforming itself into a problem-based learning school, but also in contributing to innovations in medical education. To analyse the Linköping example in order to better understand how to succeed with innovations in medical education. By applying a framework developed within the strategic management literature to the case study, the authors hope to understand how this innovation was achieved. Linköping Health University was able to break boundaries and create a divergent profile through eliminating, reducing, raising, and creating different aspects of the curricula. A strategic management framework can be applied to medical education to better understand innovation. The authors discover that many of the later innovations were in fact more aimed at sustaining the initial innovation rather than creating new trends. It remains unclear from the case study how to stimulate innovation without the use of fear or threats.

  12. Estimation of typhoon rainfall in GaoPing River: A Multivariate Maximum Entropy Method

    NASA Astrophysics Data System (ADS)

    Pei-Jui, Wu; Hwa-Lung, Yu

    2016-04-01

    The heavy rainfall from typhoons is the main factor of the natural disaster in Taiwan, which causes the significant loss of human lives and properties. Statistically average 3.5 typhoons invade Taiwan every year, and the serious typhoon, Morakot in 2009, impacted Taiwan in recorded history. Because the duration, path and intensity of typhoon, also affect the temporal and spatial rainfall type in specific region , finding the characteristics of the typhoon rainfall type is advantageous when we try to estimate the quantity of rainfall. This study developed a rainfall prediction model and can be divided three parts. First, using the EEOF(extended empirical orthogonal function) to classify the typhoon events, and decompose the standard rainfall type of all stations of each typhoon event into the EOF and PC(principal component). So we can classify the typhoon events which vary similarly in temporally and spatially as the similar typhoon types. Next, according to the classification above, we construct the PDF(probability density function) in different space and time by means of using the multivariate maximum entropy from the first to forth moment statistically. Therefore, we can get the probability of each stations of each time. Final we use the BME(Bayesian Maximum Entropy method) to construct the typhoon rainfall prediction model , and to estimate the rainfall for the case of GaoPing river which located in south of Taiwan.This study could be useful for typhoon rainfall predictions in future and suitable to government for the typhoon disaster prevention .

  13. Determining the Technical Standards of Ping Pong Table by Using Close Range Photogrammetry

    NASA Astrophysics Data System (ADS)

    Acar, U.; Bayram, B.; Cetin, H. I.; Sanlı, F. B.

    2012-07-01

    In the presented study, quality measurements were made regarding three different ping pong tables that were produced with three different materials. Measurements were made on the purpose of confirming whether the tables can be used as a match table that is in the standard of International Table Tennis Federation or not. For this confirmation, bouncing height of the table tennis ball is measured which is approved by ITTF. Average bouncing height that is required by federation standards is minimum 23 cm for free falling table tennis ball from 30 cm. In order to locate the bounce on the tables, the table tennis ball is released from 30cm in free fall with equipment was. In the meantime, 24 video frames videos were shot with a Full HD (1920 × 1080) camera. Each frame of videos that were taken is separated from each other. Each frame is analyzed and highest bounce is measured. As a result of the study, the bouncing heights of the three tables were measured as 23.04 cm, 23.33 cm, 22.91 cm for table1, for table2 and for table3 respectively.

  14. Synergistic "ping-pong" energy transfer for efficient light activation in a chromophore-catalyst dyad.

    PubMed

    Quaranta, Annamaria; Charalambidis, Georgios; Herrero, Christian; Margiola, Sofia; Leibl, Winfried; Coutsolelos, Athanassios; Aukauloo, Ally

    2015-10-07

    The synthesis of a porphyrin-Ru(II) polypyridine complex where the porphyrin acts as a photoactive unit and the Ru(II) polypyridine as a catalytic precursor is described. Comparatively, the free base porphyrin was found to outperform the ruthenium based chromophore in the yield of light induced electron transfer. Mechanistic insights indicate the occurrence of a ping-pong energy transfer from the (1)LC excited state of the porphyrin chromophore to the (3)MCLT state of the catalyst and back to the (3)LC excited state of the porphyrin unit. The latter, triplet-triplet energy transfer back to the chromophore, efficiently competes with fast radiationless deactivation of the excited state at the catalyst site. The energy thus recovered by the chromophore allows improved yield of formation of the oxidized form of the chromophore and concomitantly of the oxidation of the catalytic unit by intramolecular charge transfer. The presented results are among the rare examples where a porphyrin chromophore is successfully used to drive an oxidative activation process where reductive processes prevail in the literature.

  15. An improved control mode for the ping-pong protocol operation in imperfect quantum channels

    NASA Astrophysics Data System (ADS)

    Zawadzki, Piotr

    2015-07-01

    Quantum direct communication (QDC) can bring confidentiality of sensitive information without any encryption. A ping-pong protocol, a well-known example of entanglement-based QDC, offers asymptotic security in a perfect quantum channel. However, it has been shown (Wójcik in Phys Rev Lett 90(15):157901, 2003. doi:10.1103/PhysRevLett.90.157901) that it is not secure in the presence of losses. Moreover, legitimate parities cannot rely on dense information coding due to possible undetectable eavesdropping even in the perfect setting (Pavičić in Phys Rev A 87(4):042326, 2013. doi:10.1103/PhysRevA.87.042326). We have identified the source of the above-mentioned weaknesses in the incomplete check of the EPR pair coherence. We propose an improved version of the control mode, and we discuss its relation to the already-known attacks that undermine the QDC security. It follows that the new control mode detects these attacks with high probability and independently on a quantum channel type. As a result, an asymptotic security of the QDC communication can be maintained for imperfect quantum channels, also in the regime of dense information coding.

  16. Transposition of the Tourist-MITE mPing in yeast: an assay that retains key features of catalysis by the class 2 PIF/Harbinger superfamily

    PubMed Central

    2010-01-01

    Background PIF/Harbinger is the most recently discovered DNA transposon superfamily and is now known to populate genomes from fungi to plants to animals. Mobilization of superfamily members requires two separate element-encoded proteins (ORF1 and TPase). Members of this superfamily also mobilize Tourist-like miniature inverted repeat transposable elements (MITEs), which are the most abundant transposable elements associated with the genes of plants, especially the cereal grasses. The phylogenetic analysis of many plant genomes indicates that MITEs can amplify rapidly from one or a few elements to hundreds or thousands. The most active DNA transposon identified to date in plants or animals is mPing, a rice Tourist-like MITE that is a deletion derivative of the autonomous Ping element. Ping and the closely related Pong are the only known naturally active PIF/Harbinger elements. Some rice strains accumulate ~40 new mPing insertions per plant per generation. In this study we report the development of a yeast transposition assay as a first step in deciphering the mechanism underlying the amplification of Tourist-MITEs. Results The ORF1 and TPase proteins encoded by Ping and Pong have been shown to mobilize mPing in rice and in transgenic Arabidopsis. Initial tests of the native proteins in a yeast assay resulted in very low transposition. Significantly higher activities were obtained by mutation of a putative nuclear export signal (NES) in the TPase that increased the amount of TPase in the nucleus. When introduced into Arabidopsis, the NES mutant protein also catalyzed higher frequencies of mPing excision from the gfp reporter gene. Our yeast assay retains key features of excision and insertion of mPing including precise excision, extended insertion sequence preference, and a requirement for two proteins that can come from either Ping or Pong or both elements. Conclusions The yeast transposition assay provides a robust platform for analysis of the mechanism underlying

  17. The NIH Toolbox Cognition Battery: Results from a Large Normative Developmental Sample (PING)

    PubMed Central

    Akshoomoff, Natacha; Newman, Erik; Thompson, Wesley K.; McCabe, Connor; Bloss, Cinnamon S.; Chang, Linda; Amaral, David G.; Casey, B. J.; Ernst, Thomas M.; Frazier, Jean A.; Gruen, Jeffrey R.; Kaufmann, Walter E.; Kenet, Tal; Kennedy, David N.; Libiger, Ondrej; Mostofsky, Stewart; Murray, Sarah S.; Sowell, Elizabeth R.; Schork, Nicholas; Dale, Anders M.; Jernigan, Terry L.

    2014-01-01

    Objective The NIH Toolbox Cognition Battery (NTCB) was designed to provide a brief, efficient computerized test of key neuropsychological functions appropriate for use in children as young as 3 years of age. This report describes the performance of a large group of typically developing children and adolescents and examines the impact of age and sociocultural variables on test performance. Method The NTCB was administered to a sample of 1020 typically developing males and females ranging in age from 3 to 20 years, diverse in terms of socioeconomic status (SES) and race/ethnicity, as part of the new publicly accessible Pediatric Imaging, Neurocognition, and Genetics (PING) data resource, at 9 sites across the United States. Results General additive models of nonlinear age-functions were estimated from age-differences in test performance on the 8 NTCB subtests while controlling for family SES and genetic ancestry factors (GAFs). Age accounted for the majority of the variance across all NTCB scores, with additional significant contributions of gender on some measures, and of SES and race/ethnicity (GAFs) on all. After adjusting for age and gender, SES and GAFs explained a substantial proportion of the remaining unexplained variance in Picture Vocabulary scores. Conclusions The results highlight the sensitivity to developmental effects and efficiency of this new computerized assessment battery for neurodevelopmental research. Limitations are observed in the form of some ceiling effects in older children, some floor effects, particularly on executive function tests in the youngest participants, and evidence for variable measurement sensitivity to cultural/socioeconomic factors. PMID:24219608

  18. Quality control of waste to incineration--waste composition analysis in Lidköping, Sweden.

    PubMed

    Petersen, Cecilia Mattsson; Berg, Per E O; Rönnegård, Lars

    2005-12-01

    In order to decrease environmental impacts in waste management the choice of treatment method must be based on the characteristics of the waste. Present sampling procedures do not provide statistically representative samples of solid waste and this provides difficulties in characterization. The objective of this study was to develop a procedure for waste component analysis and sampling of waste after collection and at plant level. A further objective was to characterize the waste delivered to an incineration plant for physical and chemical properties and to determine the amounts of delivered waste that could be classified as biofuels and fossil fuels. The proportions of recyclables and hazardous waste were also examined. Samples were taken randomly from waste trucks and divided by square implementation. Statistical analysis of the results showed that the number of sub-samples could be decreased with only a moderate increase in the confidence interval. This means that future waste composition analyses could be made more efficient and thereby less expensive. The analysis of the waste delivered to the Lidköping incineration plant (Central Sweden) showed that 66.4% of the household waste was composed of biofuels and 21.3% of non-renewable combustibles, of which 40.3% were recyclables. In addition, 11.6% of the household waste was non-combustible and 0.6% hazardous waste. The heat value for the biofuels was 18.0-19.7 MJ kg(-1) dry mass (DM) and for the fossil fuels 28.2-33.9 MJ kg(-1) DM. The industrial waste consisted of 35.9% biofuels, 62.0% fossil fuels, 1.6% non-combustible and 0.5% hazardous waste. The heat value was 19.5 MJ kg(-1) DM for the biofuels and 31.4 MJ kg(-1) DM for the fossil fuels.

  19. The characteristics of a low background germanium gamma ray spectrometer at China JinPing Underground Laboratory.

    PubMed

    Zeng, Zhi; Mi, Yuhao; Ma, Hao; Cheng, Jianping; Su, Jian; Yue, Qian

    2014-09-01

    A low background germanium gamma ray spectrometer, GeTHU, has been installed at China JinPing Underground Laboratory (CJPL). The integral background count rate of the spectrometer was 0.629 cpm between 40 and 2700 keV, the origins of which were studied by Monte Carlo simulation. Detection limits and efficiencies were calculated for selected gamma peaks. Some samples of rare event experiments were measured and (137)Cs contamination was found in boric acid. GeTHU will be mainly used to measure environmental samples and screen materials in dark matter and double beta decay experiments. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Fei-Liu-Ping ointment inhibits lung cancer growth and invasion by suppressing tumor inflammatory microenvironment

    PubMed Central

    2014-01-01

    Background Lung cancer is one of the leading causes of cancer-related mortality worldwide. Conventional chemotherapy and radiotherapy are the primary therapeutic methods for lung cancer with the use of combination therapies gaining popularity. The frequency and duration of treatment, as well as, managing lung cancer by targeting multiple aspects of cancer biology is often limited by toxicity to the patient. There are many naturally occurring anticancer agents that have a high degree of efficacy and low toxicity, offering a viable and safe approach for the treatment of lung cancer. The herbs traditionally used in Chinese medicine for anticancer treatment offer great potential to enhance the efficacy of conventional therapy. In this study, we evaluated the synergistic effects of Fei-Liu-Ping (FLP) ointment in treating lung cancer; a known anticancer Chinese herbal based formula. Methods In this study, A549 human lung carcinoma cell line and Lewis lung carcinoma xenograft mouse model were used. In addition, we utilized an in vitro co-culture system to simulate the tumor microenvironment in order to evaluate the molecular mechanisms of FLP treatment. Results FLP treatment significantly inhibited tumor growth in the Lewis lung xenograft by 40 percent, compared to that of cyclophosphamide (CTX) of 62.02 percent. Moreover, combining FLP and CTX inhibited tumor growth by 83.23 percent. Upon evaluation, we found that FLP treatment reduced the concentration of serum pro-inflammatory cytokines IL-6, TNF-α, and IL-1β. In addition, we also found an improvement in E-cadherin expression and inhibition of N-cadherin and MMP9. We found similar findings in vitro when we co-cultured A549 cells with macrophages. FLP treatment inhibited A549 cell growth, invasion and metastasis, in part, through the regulation of NF-κB and altering the expression of E-cadherin, N-cadherin, MMP2 and MMP9. Conclusions FLP exerts anti-inflammatory properties in the tumor microenvironment, which may

  1. Librarians as Advocates of Social Media for Researchers: A Social Media Project Initiated by Linköping University Library, Sweden

    ERIC Educational Resources Information Center

    Persson, Sassa; Svenningsson, Maria

    2016-01-01

    Librarians at Linköping University help researchers keep abreast of developments in their fields and to increase the visibility of their work. Strategic, professional use of social media ought to be an essential part of a researcher's communication strategy. This article investigates the level of awareness of the professional use of social media…

  2. Exploring a Conceptual Model-Based Approach to Teaching Situated Word Problems: A Response to Yan Ping Xin and Dake Zhang

    ERIC Educational Resources Information Center

    Jitendra, Asha K.

    2011-01-01

    This article presents the author's response to Yan Ping Xin and Dake Zhang's recent critical evaluation of her and colleagues' work in "Exploring a Conceptual Model-Based Approach to Teaching Situated Word Problems," published in "The Journal of Educational Research" in 2009 (Vol. 102, No. 6). Most critiques of prior research are written in a fair…

  3. Tales of Recombinant Femininity: "The Reincarnation of Golden Lotus," the "Chin P'ing Mei," and the Politics of Melodrama in Hong Kong.

    ERIC Educational Resources Information Center

    Fore, Steve

    1993-01-01

    Examines the film "The Reincarnation of Golden Lotus" and the text upon which it is loosely based, the "Chin P'ing Mei," and the relationship between it and modern Chinese culture. States that the film's screenplay is much less an adaptation of the source novel than it is a female-centered reworking of a particular narrative…

  4. Librarians as Advocates of Social Media for Researchers: A Social Media Project Initiated by Linköping University Library, Sweden

    ERIC Educational Resources Information Center

    Persson, Sassa; Svenningsson, Maria

    2016-01-01

    Librarians at Linköping University help researchers keep abreast of developments in their fields and to increase the visibility of their work. Strategic, professional use of social media ought to be an essential part of a researcher's communication strategy. This article investigates the level of awareness of the professional use of social media…

  5. Tales of Recombinant Femininity: "The Reincarnation of Golden Lotus," the "Chin P'ing Mei," and the Politics of Melodrama in Hong Kong.

    ERIC Educational Resources Information Center

    Fore, Steve

    1993-01-01

    Examines the film "The Reincarnation of Golden Lotus" and the text upon which it is loosely based, the "Chin P'ing Mei," and the relationship between it and modern Chinese culture. States that the film's screenplay is much less an adaptation of the source novel than it is a female-centered reworking of a particular narrative…

  6. Assessing Lexicon: Validation and Developmental Data of the Picture Naming Game (PiNG), a New Picture Naming Task for Toddlers

    ERIC Educational Resources Information Center

    Bello, A.; Giannantoni, P.; Pettenati, P.; Stefanini, S.; Caselli, M. C.

    2012-01-01

    Background: Understanding lexical abilities in infants and toddlers is important, yet no single tool can be used. Aims: To perform a validation of a new tool (known as the Picture Naming Game, or "PiNG") for assessing lexical comprehension and production in toddlers and to obtain developmental trends for Italian children. Methods &…

  7. Assessing Lexicon: Validation and Developmental Data of the Picture Naming Game (PiNG), a New Picture Naming Task for Toddlers

    ERIC Educational Resources Information Center

    Bello, A.; Giannantoni, P.; Pettenati, P.; Stefanini, S.; Caselli, M. C.

    2012-01-01

    Background: Understanding lexical abilities in infants and toddlers is important, yet no single tool can be used. Aims: To perform a validation of a new tool (known as the Picture Naming Game, or "PiNG") for assessing lexical comprehension and production in toddlers and to obtain developmental trends for Italian children. Methods &…

  8. Exploring a Conceptual Model-Based Approach to Teaching Situated Word Problems: A Response to Yan Ping Xin and Dake Zhang

    ERIC Educational Resources Information Center

    Jitendra, Asha K.

    2011-01-01

    This article presents the author's response to Yan Ping Xin and Dake Zhang's recent critical evaluation of her and colleagues' work in "Exploring a Conceptual Model-Based Approach to Teaching Situated Word Problems," published in "The Journal of Educational Research" in 2009 (Vol. 102, No. 6). Most critiques of prior research are written in a fair…

  9. Coxsackie virus B antibodies are increased in HLA DR3-MICA5.1 positive type 1 diabetes patients in the Linköping region of Sweden.

    PubMed

    Gupta, Manu; Nikitina-Zake, Liene; Landin-Olsson, Mona; Kockum, Ingrid; Sanjeevi, Carani B

    2003-09-01

    Type 1 diabetes mellitus (T1DM) is an autoimmune disorder in which genetics and environmental factors play a role. Among the environmental factors, viruses (especially Coxsackie virus B [CBV]), and among genetic markers, human leukocyte antigen (HLA) DRB1*04-DQA1*0301-DQB1*0302 (DR4-DQ8) and DRB1*03-DQA1*0501-DQB1*0201 (DR3-DQ2), and major histocompatibility complex class I chain-related gene-A (MICA) alleles 5 and 5.1 have been reported to be associated with T1DM in Caucasians. Sweden ranks third in the world for T1DM incidence. In Sweden, the Linköping region indicates the highest incidence for T1DM. In this study, we analyzed whether antibodies against CBV are increased in DR3, DR4, MICA5, or MICA5.1 positive patients from Linköping (n = 46) and from Swedish population as a whole (n = 298) between the age of 0 and 15 years old. There was no difference in the frequency of antibodies to CBV in patients compared with controls in Linköping (26% vs 23%) or in all of Sweden (26% vs 21%). However, CBV antibodies were increased in DR3, DR3-DR4 (heterozygous), DR3-MICA5.1, and DR3-DR4-MICA5.1 positive compared with DR3, DR3-DR4, DR3-MICA5.1, and DR3-DR4-MICA5.1 negative patients in Linköping (p < 0.05 for all), but not in Swedish population as a whole. Thus, our study suggests that in addition to DR3, MICA5.1 has an influence on the immune response to CBV infection in patients from Linköping.

  10. Analysis of a dual domain phosphoglycosyl transferase reveals a ping-pong mechanism with a covalent enzyme intermediate

    PubMed Central

    Das, Debasis; Kuzmic, Petr

    2017-01-01

    Phosphoglycosyl transferases (PGTs) are integral membrane proteins with diverse architectures that catalyze the formation of polyprenol diphosphate-linked glycans via phosphosugar transfer from a nucleotide diphosphate-sugar to a polyprenol phosphate. There are two PGT superfamilies that differ significantly in overall structure and topology. The polytopic PGT superfamily, represented by MraY and WecA, has been the subject of many studies because of its roles in peptidoglycan and O-antigen biosynthesis. In contrast, less is known about a second, extensive superfamily of PGTs that reveals a core structure with dual domain architecture featuring a C-terminal soluble globular domain and a predicted N-terminal membrane-associated domain. Representative members of this superfamily are the Campylobacter PglCs, which initiate N-linked glycoprotein biosynthesis and are implicated in virulence and pathogenicity. Despite the prevalence of dual domain PGTs, their mechanism of action is unknown. Here, we present the mechanistic analysis of PglC, a prototypic dual domain PGT from Campylobacter concisus. Using a luminescence-based assay, together with substrate labeling and kinetics-based approaches, complementary experiments were carried out that support a ping-pong mechanism involving a covalent phosphosugar intermediate for PglC. Significantly, mass spectrometry-based approaches identified Asp93, which is part of a highly conserved AspGlu dyad found in all dual domain PGTs, as the active-site nucleophile of the enzyme involved in the formation of the covalent adduct. The existence of a covalent phosphosugar intermediate provides strong support for a ping-pong mechanism of PglC, differing fundamentally from the ternary complex mechanisms of representative polytopic PGTs. PMID:28630348

  11. Analysis of a dual domain phosphoglycosyl transferase reveals a ping-pong mechanism with a covalent enzyme intermediate.

    PubMed

    Das, Debasis; Kuzmic, Petr; Imperiali, Barbara

    2017-07-03

    Phosphoglycosyl transferases (PGTs) are integral membrane proteins with diverse architectures that catalyze the formation of polyprenol diphosphate-linked glycans via phosphosugar transfer from a nucleotide diphosphate-sugar to a polyprenol phosphate. There are two PGT superfamilies that differ significantly in overall structure and topology. The polytopic PGT superfamily, represented by MraY and WecA, has been the subject of many studies because of its roles in peptidoglycan and O-antigen biosynthesis. In contrast, less is known about a second, extensive superfamily of PGTs that reveals a core structure with dual domain architecture featuring a C-terminal soluble globular domain and a predicted N-terminal membrane-associated domain. Representative members of this superfamily are the Campylobacter PglCs, which initiate N-linked glycoprotein biosynthesis and are implicated in virulence and pathogenicity. Despite the prevalence of dual domain PGTs, their mechanism of action is unknown. Here, we present the mechanistic analysis of PglC, a prototypic dual domain PGT from Campylobacter concisus Using a luminescence-based assay, together with substrate labeling and kinetics-based approaches, complementary experiments were carried out that support a ping-pong mechanism involving a covalent phosphosugar intermediate for PglC. Significantly, mass spectrometry-based approaches identified Asp93, which is part of a highly conserved AspGlu dyad found in all dual domain PGTs, as the active-site nucleophile of the enzyme involved in the formation of the covalent adduct. The existence of a covalent phosphosugar intermediate provides strong support for a ping-pong mechanism of PglC, differing fundamentally from the ternary complex mechanisms of representative polytopic PGTs.

  12. Ping-pong amplification of a retroviral vector achieves high-level gene expression: human growth hormone production.

    PubMed Central

    Kozak, S L; Kabat, D

    1990-01-01

    Retroviral vectors offer major advantages for gene transfer studies but have not been useful for producing proteins in large quantities. This deficiency has resulted in part from interference to superinfection, which limits the numbers of active proviruses in cells. Recently, we found that these vectors amplify when they are added as calcium phosphate precipitates to cocultures of cells that package retroviruses into ecotropic and amphotropic host range envelopes. Helper-free virions from either cell type can infect the other without interference, resulting in theoretically limitless back-and-forth (ping-pong) vector replication. In initial studies, however, amplifications of a vector that contained the human growth hormone gene ceased when the hormone produced was 0.3% or less of cellular protein synthesis. This limit was caused by two factors. First, recombinant shutoff viruses that are replication defective and encode envelope glycoproteins form at a low probability during any round of the vector replication cycle and these spread in cocultures, thereby establishing interference. Single cells in shutoff cocultures therefore synthesize both ecotropic and amphotropic envelope glycoproteins, and they release promiscuous (presumably hybrid) virions. The probability of forming shutoff viruses before the vector had amplified to a high multiplicity was reduced by using small cocultures. Second, cells with large numbers of proviruses are unhealthy and their proviral expression can be unstable. Stable expresser cell clones were obtained by selection. Thereby, cell lines were readily obtained that stably produce human growth hormone as 4 to 6% of the total protein synthesis. A ping-pong retroviral vector can be used for high-level protein production in vertebrate cells. Images PMID:2352330

  13. Li(+) solvation in glyme-Li salt solvate ionic liquids.

    PubMed

    Ueno, Kazuhide; Tatara, Ryoichi; Tsuzuki, Seiji; Saito, Soshi; Doi, Hiroyuki; Yoshida, Kazuki; Mandai, Toshihiko; Matsugami, Masaru; Umebayashi, Yasuhiro; Dokko, Kaoru; Watanabe, Masayoshi

    2015-03-28

    Certain molten complexes of Li salts and solvents can be regarded as ionic liquids. In this study, the local structure of Li(+) ions in equimolar mixtures ([Li(glyme)]X) of glymes (G3: triglyme and G4: tetraglyme) and Li salts (LiX: lithium bis(trifluoromethanesulfonyl)amide (Li[TFSA]), lithium bis(pentafluoroethanesulfonyl)amide (Li[BETI]), lithium trifluoromethanesulfonate (Li[OTf]), LiBF4, LiClO4, LiNO3, and lithium trifluoroacetate (Li[TFA])) was investigated to discriminate between solvate ionic liquids and concentrated solutions. Raman spectra and ab initio molecular orbital calculations have shown that the glyme molecules adopt a crown-ether like conformation to form a monomeric [Li(glyme)](+) in the molten state. Further, Raman spectroscopic analysis allowed us to estimate the fraction of the free glyme in [Li(glyme)]X. The amount of free glyme was estimated to be a few percent in [Li(glyme)]X with perfluorosulfonylamide type anions, and thereby could be regarded as solvate ionic liquids. Other equimolar mixtures of [Li(glyme)]X were found to contain a considerable amount of free glyme, and they were categorized as traditional concentrated solutions. The activity of Li(+) in the glyme-Li salt mixtures was also evaluated by measuring the electrode potential of Li/Li(+) as a function of concentration, by using concentration cells against a reference electrode. At a higher concentration of Li salt, the amount of free glyme diminishes and affects the electrode reaction, leading to a drastic increase in the electrode potential. Unlike conventional electrolytes (dilute and concentrated solutions), the significantly high electrode potential found in the solvate ILs indicates that the solvation of Li(+) by the glyme forms stable and discrete solvate ions ([Li(glyme)](+)) in the molten state. This anomalous Li(+) solvation may have a great impact on the electrode reactions in Li batteries.

  14. Solubility of Li/sub 2/S in LiF-LiCl-LiBr electrolyte: measurements and calculations

    SciTech Connect

    Tomczuk, Z.; Vissers, D.R.; Saboungi, M.L.

    1983-01-01

    High performance lithium-alloy/iron sulfide cells are currently being developed at Argonne National Laboratory and at several industrial firms for electric vehicle propulsion. These cells operate at high temperatures and utilize Li-Al or Li-Si negative electrodes, FeS positive electrodes, and a molten salt electrolyte. In the early work, the molten salt was the LiCl-KCl eutectic (58.2 mol % LiCl-41.8 mol % KCl), but in recent work various electrolyte compositions have been used, i.e., LiCl-rich LiCl--KCl (typically 67 mole % LiCl), LiF-LiCl-KCl, or LiF-LiCl-LiBr (1). The use of these electrolytes requires cell operating temperatures in the range of 703-773 K. As these cells are cycled, it has been shown that, when LiCl-KCl electrolytes were used, local electrolyte compositional changes occurred because of ion transport processes and chemical reactions in the cells. However, despite the temperature or the nature of the electrolyte, iron and lithium sulfide are the final discharge products. Thus, a systematic investigation of the solubility of Li/sub 2/S in a variety of electrolytes containing LiCl as a function of temperature is of technological importance in the development of these cells. We report new solubility measurements of Li/sub 2/S in the LiF-LiCl--LiBr eutectic solution (22 mol %-31 mol %-47 mol %) at 739 and 773 K. The observed increase of Li/sub 2/S solubility as the solvent is changed from LiCl-KCl to LiF-LiCl-LiBr and then to LiF-LiCl is explained in terms of known molten salt theories.

  15. The Effects of Climate Change on the Hydrology and Water Resources of the Bhumibol DAM, Upper Ping River Basin, Thailand

    NASA Astrophysics Data System (ADS)

    Ishida, K.; Wuthiwongyothin, S.

    2016-12-01

    The effects of climate change on the hydrology and water resources of the Bhumibol Dam, Upper Ping River Basin, Thailand are assessed by utilizing SRES-climate scenarios during the 21st century from ECHAM5 and CCSM3. The hydrologic response of streamflow in the upper Ping River basin to the climate change is performed under A1B, A2 and B1 with total 12 projections. The Watershed Environmental Hydrology-Hydro Climate Model (WEHY-HCM) is used to perform dynamical downscaling the global atmospheric scale ( 200 km) to the regional atmospheric scale over the study basin via MM5 by refining scale to 9 km grid resolution at hourly time scale. The watershed module then couples the atmospheric and the land surface hydrology processes with its physically based model feather and simulates the watershed flows. The GCM-historical control runs (1971 to 2000) were downscaled, corrected their bias, and tested the models performance by a well matching of cumulative distribution function between the model and observed flows. The projected flows from 2001 to 2015 and observed flows were compared, and showed a projected range covering the observed time series. With these GCMs reliability in producing future climate variables, the future hydrologic flows of the study area can be generating flows and studying the effects of the climate change. Based on the ensemble average of 12 realizations, the result shows that toward the 21st century the future projected flows yield a significant upward trend by the Mann-Kendall trend test at 95% confidence level. The study basin will have more streamflow increase 17.3% (6.36 billion m3) compared to the average flows from 1988 to 2015 (5.24 billion m3). These flows will supply to the Bhumibol dam, which it has a total storage 13.4 billion m3 and active storage 9.7 billion m3. Thus, the increasing of ensemble mean accumulated annual flow is still less that the dam storage capacities, which will have space to receive more water at about 4 to 8 billion

  16. Presence of Li Clusters in Molten LiCl-Li

    NASA Astrophysics Data System (ADS)

    Merwin, Augustus; Phillips, William C.; Williamson, Mark A.; Willit, James L.; Motsegood, Perry N.; Chidambaram, Dev

    2016-05-01

    Molten mixtures of lithium chloride and metallic lithium are of significant interest in various metal oxide reduction processes. These solutions have been reported to exhibit seemingly anomalous physical characteristics that lack a comprehensive explanation. In the current work, the physical chemistry of molten solutions of lithium chloride and metallic lithium, with and without lithium oxide, was investigated using in situ Raman spectroscopy. The Raman spectra obtained from these solutions were in agreement with the previously reported spectrum of the lithium cluster, Li8. This observation is indicative of a nanofluid type colloidal suspension of Li8 in a molten salt matrix. It is suggested that the formation and suspension of lithium clusters in lithium chloride is the cause of various phenomena exhibited by these solutions that were previously unexplainable.

  17. Presence of Li Clusters in Molten LiCl-Li.

    PubMed

    Merwin, Augustus; Phillips, William C; Williamson, Mark A; Willit, James L; Motsegood, Perry N; Chidambaram, Dev

    2016-05-05

    Molten mixtures of lithium chloride and metallic lithium are of significant interest in various metal oxide reduction processes. These solutions have been reported to exhibit seemingly anomalous physical characteristics that lack a comprehensive explanation. In the current work, the physical chemistry of molten solutions of lithium chloride and metallic lithium, with and without lithium oxide, was investigated using in situ Raman spectroscopy. The Raman spectra obtained from these solutions were in agreement with the previously reported spectrum of the lithium cluster, Li8. This observation is indicative of a nanofluid type colloidal suspension of Li8 in a molten salt matrix. It is suggested that the formation and suspension of lithium clusters in lithium chloride is the cause of various phenomena exhibited by these solutions that were previously unexplainable.

  18. Presence of Li clusters in molten LiCl-Li

    DOE PAGES

    Merwin, Augustus; Phillips, William C.; Williamson, Mark A.; ...

    2016-05-05

    Molten mixtures of lithium chloride and metallic lithium are of significant interest in various metal oxide reduction processes. These solutions have been reported to exhibit seemingly anomalous physical characteristics that lack a comprehensive explanation. ln the current work, the physical chemistry of molten solutions of lithium chloride and metallic lithium, with and without lithium oxide, was investigated using in situ Raman spectroscopy. The Raman spectra obtained from these solutions were in agreement with the previously reported spectrum of the lithium cluster, Li8. Furthermore, this observation is indicative of a nanofluid type colloidal suspension of Li8, in a molten salt matrix.more » It is suggested that the formation and suspension of lithium clusters in lithium chloride is the cause of various phenomena exhibited by these solutions that were previously unexplainable.« less

  19. Presence of Li clusters in molten LiCl-Li

    SciTech Connect

    Merwin, Augustus; Phillips, William C.; Williamson, Mark A.; Willit, James L.; Motsegood, Perry N.; Chidambaram, Dev

    2016-05-05

    Molten mixtures of lithium chloride and metallic lithium are of significant interest in various metal oxide reduction processes. These solutions have been reported to exhibit seemingly anomalous physical characteristics that lack a comprehensive explanation. ln the current work, the physical chemistry of molten solutions of lithium chloride and metallic lithium, with and without lithium oxide, was investigated using in situ Raman spectroscopy. The Raman spectra obtained from these solutions were in agreement with the previously reported spectrum of the lithium cluster, Li8. Furthermore, this observation is indicative of a nanofluid type colloidal suspension of Li8, in a molten salt matrix. It is suggested that the formation and suspension of lithium clusters in lithium chloride is the cause of various phenomena exhibited by these solutions that were previously unexplainable.

  20. Presence of Li Clusters in Molten LiCl-Li

    PubMed Central

    Merwin, Augustus; Phillips, William C.; Williamson, Mark A.; Willit, James L.; Motsegood, Perry N.; Chidambaram, Dev

    2016-01-01

    Molten mixtures of lithium chloride and metallic lithium are of significant interest in various metal oxide reduction processes. These solutions have been reported to exhibit seemingly anomalous physical characteristics that lack a comprehensive explanation. In the current work, the physical chemistry of molten solutions of lithium chloride and metallic lithium, with and without lithium oxide, was investigated using in situ Raman spectroscopy. The Raman spectra obtained from these solutions were in agreement with the previously reported spectrum of the lithium cluster, Li8. This observation is indicative of a nanofluid type colloidal suspension of Li8 in a molten salt matrix. It is suggested that the formation and suspension of lithium clusters in lithium chloride is the cause of various phenomena exhibited by these solutions that were previously unexplainable. PMID:27145895

  1. Madame Li Li: Communist Revolutionary, Adult Educator, Lifelong Learner

    ERIC Educational Resources Information Center

    Boshier, Roger; Huang, Yan

    2009-01-01

    Prior to 1949 the Chinese Communist Party orchestrated innovative and participatory forms of adult education. This article concerns Madame Li Li, a leading Chinese Communist woman adult educator. Western delegates at the International Council for Adult Education 1984 Shanghai symposium on adult education were fascinated by Madame Li Li because,…

  2. Madame Li Li: Communist Revolutionary, Adult Educator, Lifelong Learner

    ERIC Educational Resources Information Center

    Boshier, Roger; Huang, Yan

    2009-01-01

    Prior to 1949 the Chinese Communist Party orchestrated innovative and participatory forms of adult education. This article concerns Madame Li Li, a leading Chinese Communist woman adult educator. Western delegates at the International Council for Adult Education 1984 Shanghai symposium on adult education were fascinated by Madame Li Li because,…

  3. Protective effects of Ping-Lv-Mixture (PLM), a medicinal formula on arrhythmias induced by myocardial ischemia-reperfusion.

    PubMed

    An, Wei; Yang, Jing

    2006-11-03

    Ping-Lv-Mixture (PLM) is a Chinese medicinal formula. The present study aimed to determine the effects of PLM on myocardial ischemia-reperfusion (MI/R) induced arrhythmias in rats. Arrhythmia model was established by occlusion of the left arterial descending coronary artery and thereafter reperfusion. A lead II electrocardiogram was monitored throughout the experiment. The results showed that pretreatment of PLM to MI/R rats significantly reduced the incidence and duration of ventricular tachycardia and ventricular fibrillation. On induction of MI/R, the activities of creatine kinase and lactate dehydrogenase were increased in vehicle group. PLM (0.04-1.00 g/kg) administration prevented the increase of these enzymes. Moreover, a significant increase of myocardium superoxide dismutase and decrease of malondialdehyde contents were observed in rats of PLM groups. On the other hand, the expressions of platelet activating factor (PAF) receptor mRNA was down-regulated in a dose-dependent manner in the PLM-treated groups by RT-PCR. Thus, it can be concluded that pretreatment with PLM inhibited lipid peroxidation in rats through suppressing the expression of PAF receptor, which may contribute to its preventive effect on myocardial ischemia-reperfusion induced arrhythmias.

  4. Removal of pharmaceutical residues using ozonation as intermediate process step at Linköping WWTP, Sweden.

    PubMed

    Baresel, Christian; Malmborg, Jonas; Ek, Mats; Sehlén, Robert

    2016-01-01

    Pilot tests as basis for the design, implementation and operation of a future full-scale oxidation plant completing the existing sewage treatment in Linköping, Sweden, were performed. Using an ozonation step between bio-sedimentation and post-denitrification processes, the primary goal was the removal of the highest priority substances to effluent water levels that will not cause adverse effects in the recipient considering the natural dilution. The study included initial emission screenings, dose control trials, treatment performance studies and eco-toxicity studies. At an ozone dose of 5 mg O3/L, most substances could be removed. Ecotoxicological tests showed no negative effect for the tested ozone doses. High levels of oxygen into the denitrification could be rapidly reduced in the biology. The number of bacteria in the treated water could be significantly reduced even at relatively low ozone doses. Based on these results, the planning for the full-scale implementation of the treatment system was initiated in 2015.

  5. Persistence of pro-arrhythmic spatio-temporal calcium patterns in atrial myocytes: a computational study of ping waves.

    PubMed

    Thul, Rüdiger; Coombes, Stephen; Bootman, Martin D

    2012-01-01

    Clusters of ryanodine receptors within atrial myocytes are confined to spatially separated layers. In many species, these layers are not juxtaposed by invaginations of the plasma membrane (transverse tubules; 'T-tubules'), so that calcium-induced-calcium signals rely on centripetal propagation rather than voltage-synchronized channel openings to invade the interior of the cell and trigger contraction. The combination of this specific cellular geometry and dynamics of calcium release can lead to novel autonomous spatio-temporal calcium waves, and in particular ping waves. These are waves of calcium release activity that spread as counter-rotating sectors of elevated calcium within a single layer of ryanodine receptors, and can seed further longitudinal calcium waves. Here we show, using a computational model, that these calcium waves can dominate the response of a cell to electrical pacing and hence are pro-arrhythmic. This highlights the importance of modeling internal cellular structures when investigating mechanisms of cardiac dysfunction such as atrial arrhythmia.

  6. Persistence of Pro-Arrhythmic Spatio-Temporal Calcium Patterns in Atrial Myocytes: A Computational Study of Ping Waves

    PubMed Central

    Thul, Rüdiger; Coombes, Stephen; Bootman, Martin D.

    2012-01-01

    Clusters of ryanodine receptors within atrial myocytes are confined to spatially separated layers. In many species, these layers are not juxtaposed by invaginations of the plasma membrane (transverse tubules; ‘T-tubules’), so that calcium-induced-calcium signals rely on centripetal propagation rather than voltage-synchronized channel openings to invade the interior of the cell and trigger contraction. The combination of this specific cellular geometry and dynamics of calcium release can lead to novel autonomous spatio-temporal calcium waves, and in particular ping waves. These are waves of calcium release activity that spread as counter-rotating sectors of elevated calcium within a single layer of ryanodine receptors, and can seed further longitudinal calcium waves. Here we show, using a computational model, that these calcium waves can dominate the response of a cell to electrical pacing and hence are pro-arrhythmic. This highlights the importance of modeling internal cellular structures when investigating mechanisms of cardiac dysfunction such as atrial arrhythmia. PMID:22934033

  7. Application of downscaled precipitation for hydrological climate-change impact assessment in the upper Ping River Basin of Thailand

    NASA Astrophysics Data System (ADS)

    Sharma, Devesh; Babel, Mukand S.

    2013-11-01

    This paper assesses the impacts of climate change on water resources in the upper Ping River Basin of Thailand. A rainfall-runoff model is used to estimate future runoff based on the bias corrected and downscaled ECHAM4/OPYC general circulation model (GCM) precipitation scenarios for three future 5-year periods; the 2023-2027 (2025s), the 2048-2052 (2050s) and 2093-2097 (2095s). Bias-correction and spatial disaggregation techniques are applied to improve the characteristics of raw ECHAM4/OPYC precipitation. Results of future simulations suggest a decrease of 13-19 % in annual streamflow compared to the base period (1998-2002). Results also indicate that there will be a shift in seasonal streamflow pattern. Peak flows in future periods will occur in October-November rather than September as observed in the base period. There will be a significant increase in the streamflow in April with overall decrease in streamflow during the rainy season (May-October) and an increase during the dry season (November-April) for all future time periods considered in the study.

  8. Implementing web-based ping-pong-type e-communication to enhance staff satisfaction, multidisciplinary cooperation, and clinical effectiveness

    PubMed Central

    Yeh, Pei-Han; Hung, Shih-Kai; Lee, Moon-Sing; Chiou, Wen-Yen; Lai, Chun-Liang; Tsai, Wei-Ta; Hsieh, Hui-Ling; Shih, Yi-Ting; Chen, Liang-Cheng; Huang, Li-Wen; Lin, Yi-An; Lin, Po-Hao; Lin, Yung-Hsiang; Liu, Dai-Wei; Hsu, Feng-Chun; Tsai, Shiang-Jiun; Liu, Jia-Chi; Chung, En-Seu; Lin, Hon-Yi

    2016-01-01

    Abstract Background: Frequent multidisciplinary communication is essential in conducting daily radiotherapy (RT) practice. However, traditional oral or paper-based communication has limitations. E-communication has been suggested, but its effects are still not well demarcated in the field of radiation oncology. Objects: In our web-based integrated information platform, we constructed a ping-pong-type e-communication function to transfer specific notations among multidisciplinary RT staffs. The purpose was to test whether applying this e-communication can increase effectiveness of multidisciplinary cooperation when compared with oral or paper-based practice. Staff satisfaction and clinical benefits were also demonstrated. Design and setting: A real-world quality-improving study was conducted in a large center of radiation oncology. Participants and dataset used: Before and after applying multidisciplinary e-communication (from 2014 to 2015), clinical RT staffs were surveyed for their user experience and satisfaction (n = 23). For measuring clinical effectiveness, a secondary database of irradiated head and neck cancer patients was re-analyzed for comparing RT toxicities (n = 402). Interventions: Applying ping-pong-type multidisciplinary reflective e-communication was the main intervention. Outcome measures: For measuring staff satisfaction, eight domains were surveyed, such as timeliness, convenience, and completeness. For measuring clinical effectiveness of multidisciplinary cooperation, event rates of severe (i.e., grade 3–4) RT mucositis and dermatitis were recorded. Results: Overall, when compared with oral communication only, e-communication demonstrated multiple benefits, particularly on notation-review convenience (2.00 ± 1.76 vs 9.19 ± 0.81; P < 0.0001). When compared with paper-based practice, e-communication showed statistically significant benefits on all eight domains, especially on notation-review convenience (5.05 ± 2.11 vs

  9. Laser Irradiation-Induced DNA Methylation Changes Are Heritable and Accompanied with Transpositional Activation of mPing in Rice.

    PubMed

    Li, Siyuan; Xia, Qiong; Wang, Fang; Yu, Xiaoming; Ma, Jian; Kou, Hongping; Lin, Xiuyun; Gao, Xiang; Liu, Bao

    2017-01-01

    DNA methylation is an integral component of the epigenetic code in most higher eukaryotes. Exploring the extent to which DNA methylation can be altered under a specific condition and its heritability is important for elucidating the biological functions of this epigenetic modification. Here, we conducted MSAP analysis of rice plants with altered phenotypes subsequent to a low-dose Nd(3+)YAG laser irradiation. We found that all four methylation patterns at the 5'-CCGG sites that are analyzable by MSAP showed substantial changes in the immediately treated M0 plants. Interestingly, the frequencies of hypo- and hypermethylation were of similar extents, which largely offset each other and render the total methylation levels unchanged. Further analysis revealed that the altered methylation patterns were meiotically heritable to at least the M2 generation but accompanied with further changes in each generation. The methylation changes and their heritability of the metastable epigenetic state were verified by bisulfite sequencing of portion of the retrotranspon, Tos17, an established locus for assessing DNA methylation liability in rice. Real-time PCR assay indicated that the expression of various methylation-related chromatin genes was perturbed, and a Pearson correlation analysis showed that many of these genes, especially two AGOs (AGO4-1 and AGO4-2), were significantly correlated with the methylation pattern alterations. In addition, excisions of a MITE transposon, mPing, occurred rampantly in the laser irradiated plants and their progenies. Together, our results indicate that heritable DNA methylation changes can be readily induced by low-dose laser irradiation, and which can be accompanied by transpostional activation of transposable elements.

  10. Screening active components from Yu-ping-feng-san for regulating initiative key factors in allergic sensitization.

    PubMed

    Shen, Dandan; Xie, Xuejian; Zhu, Zhijie; Yu, Xi; Liu, Hailiang; Wang, Huizhu; Fan, Hongwei; Wang, Dawei; Jiang, Guorong; Hong, Min

    2014-01-01

    Yu-ping-feng-san (YPFS) is a Chinese medical formula that is used clinically for allergic diseases and characterized by reducing allergy relapse. Our previous studies demonstrated that YPFS efficiently inhibited T helper 2 cytokines in allergic inflammation. The underlying mechanisms of action of YPFS and its effective components remain unclear. In this study, it was shown that YPFS significantly inhibited production of thymic stromal lymphopoietin (TSLP), an epithelial cell-derived initiative factor in allergic inflammation, in vitro and in vivo. A method of human bronchial epithelial cell (16HBE) binding combined with HPLC-MS (named 16HBE-HPLC-MS) was established to explore potential active components of YPFS. The following five components bound to 16HBE cells: calycosin-7-glucoside, ononin, claycosin, sec-o-glucosylhamaudol and formononetin. Serum from YPFS-treated mice was analyzed and three major components were detected claycosin, formononetin and cimifugin. Among these, claycosin and formononetin were detected by 16HBE-HPLC-MS and in the serum of YPFS-treated mice. Claycosin and formononetin decreased the level of TSLP markedly at the initial stage of allergic inflammation in vivo. Nuclear factor (NF)-κB, a key transcription factor in TSLP production, was also inhibited by claycosin and formononetin, either in terms of transcriptional activation or its nuclear translocation in vitro. Allergic inflammation was reduced by claycosin and formononetin when they are administered only at the initial stage in a murine model of atopic contact dermatitis. Thus, epithelial cell binding combined with HPLC-MS is a valid method for screening active components from complex mixtures of Chinese medicine. It was demonstrated that the compounds screened from YPFS significantly attenuated allergic inflammation probably by reducing TSLP production via regulating NF-κB activation.

  11. Analysis of immunostimulatory activity of polysaccharide extracted from Yu-Ping-Feng in vitro and in vivo.

    PubMed

    Fan, Wentao; Zheng, Pimiao; Wang, Yang; Hao, Pan; Liu, Jianzhu; Zhao, Xiaona

    2017-09-01

    As a traditional Chinese multiherbal formula, Yu-Ping-Feng (YPF) is frequently used to treat cold, flu and inflammation-associated diseases. We aimed to evaluate the immunostimulatory effects of polysaccharide isolated from YPF (YPF-PS) in vitro and in vivo. In in vitro experiment, macrophage cell proliferation, phagocytosis rate, cytokine and costimulatory molecule release, T lymphocyte proliferation, cell cycle distribution, CD4(+) and CD8(+) T cell percentages were determined. To investigate the in vivo effects of YPF-PS treatment, different doses YPF-PS were administered to chicken vaccinated against Newcastle disease. The immune organ index, lymphocyte proliferation, antibody titer, cell cycle distribution, and the cell percentage of CD4(+) and CD8(+) were assessed. In vitro results indicated that YPF-PS at 15.62μgmL(-1) could increase the LPS-induced macrophage cell proliferation and phagocytosis rate significantly. The levels of cytokine (nitric oxide, tumor necrosis factor-alpha, interleukin-1 beta, interleukin-6, and interferon beta) and costimulatory molecules (CD80 and CD86) were also considerably enhanced. Moreover, YPF-PS could significantly enhance T lymphocyte proliferation individually or synergistically with phytohemagglutinin. It promoted lymphocyte entry into S and G2/M phases and increased the percentages of CD4(+) and CD8(+) T cells effectively. In addition, in vivo experiments showed that YPF-PS could enhance serum HI antibody titer. The results about T lymphocyte proliferation, cell cycle distribution, CD4(+) and CD8(+) cell percentages in chickens were also confirmed. YPF-PS has efficacious immunomodulatory properties and could be used as a new potential immune stimulator for food and medical purposes. Copyright © 2017. Published by Elsevier Masson SAS.

  12. The Past, Present and Future of the Meteorological Phenomena Identification Near the Ground (mPING) Project

    NASA Astrophysics Data System (ADS)

    Elmore, K. L.

    2016-12-01

    The Metorological Phenomemna Identification NeartheGround (mPING) project is an example of a crowd-sourced, citizen science effort to gather data of sufficeint quality and quantity needed by new post processing methods that use machine learning. Transportation and infrastructure are particularly sensitive to precipitation type in winter weather. We extract attributes from operational numerical forecast models and use them in a random forest to generate forecast winter precipitation types. We find that random forests applied to forecast soundings are effective at generating skillful forecasts of surface ptype with consideralbly more skill than the current algorithms, especuially for ice pellets and freezing rain. We also find that three very different forecast models yuield similar overall results, showing that random forests are able to extract essentially equivalent information from different forecast models. We also show that the random forest for each model, and each profile type is unique to the particular forecast model and that the random forests developed using a particular model suffer significant degradation when given attributes derived from a different model. This implies that no single algorithm can perform well across all forecast models. Clearly, random forests extract information unavailable to "physically based" methods because the physical information in the models does not appear as we expect. One intersting result is that results from the classic "warm nose" sounding profile are, by far, the most sensitive to the particular forecast model, but this profile is also the one for which random forests are most skillful. Finally, a method for calibrarting probabilties for each different ptype using multinomial logistic regression is shown.

  13. Screening Active Components from Yu-Ping-Feng-San for Regulating Initiative Key Factors in Allergic Sensitization

    PubMed Central

    Zhu, Zhijie; Yu, Xi; Liu, Hailiang; Wang, Huizhu; Fan, Hongwei; Wang, Dawei; Jiang, Guorong; Hong, Min

    2014-01-01

    Yu-ping-feng-san (YPFS) is a Chinese medical formula that is used clinically for allergic diseases and characterized by reducing allergy relapse. Our previous studies demonstrated that YPFS efficiently inhibited T helper 2 cytokines in allergic inflammation. The underlying mechanisms of action of YPFS and its effective components remain unclear. In this study, it was shown that YPFS significantly inhibited production of thymic stromal lymphopoietin (TSLP), an epithelial cell-derived initiative factor in allergic inflammation, in vitro and in vivo. A method of human bronchial epithelial cell (16HBE) binding combined with HPLC-MS (named 16HBE-HPLC-MS) was established to explore potential active components of YPFS. The following five components bound to 16HBE cells: calycosin-7-glucoside, ononin, claycosin, sec-o-glucosylhamaudol and formononetin. Serum from YPFS-treated mice was analyzed and three major components were detected claycosin, formononetin and cimifugin. Among these, claycosin and formononetin were detected by 16HBE-HPLC-MS and in the serum of YPFS-treated mice. Claycosin and formononetin decreased the level of TSLP markedly at the initial stage of allergic inflammation in vivo. Nuclear factor (NF)-κB, a key transcription factor in TSLP production, was also inhibited by claycosin and formononetin, either in terms of transcriptional activation or its nuclear translocation in vitro. Allergic inflammation was reduced by claycosin and formononetin when they are administered only at the initial stage in a murine model of atopic contact dermatitis. Thus, epithelial cell binding combined with HPLC-MS is a valid method for screening active components from complex mixtures of Chinese medicine. It was demonstrated that the compounds screened from YPFS significantly attenuated allergic inflammation probably by reducing TSLP production via regulating NF-κB activation. PMID:25198676

  14. Laser Irradiation-Induced DNA Methylation Changes Are Heritable and Accompanied with Transpositional Activation of mPing in Rice

    PubMed Central

    Li, Siyuan; Xia, Qiong; Wang, Fang; Yu, Xiaoming; Ma, Jian; Kou, Hongping; Lin, Xiuyun; Gao, Xiang; Liu, Bao

    2017-01-01

    DNA methylation is an integral component of the epigenetic code in most higher eukaryotes. Exploring the extent to which DNA methylation can be altered under a specific condition and its heritability is important for elucidating the biological functions of this epigenetic modification. Here, we conducted MSAP analysis of rice plants with altered phenotypes subsequent to a low-dose Nd3+YAG laser irradiation. We found that all four methylation patterns at the 5′-CCGG sites that are analyzable by MSAP showed substantial changes in the immediately treated M0 plants. Interestingly, the frequencies of hypo- and hypermethylation were of similar extents, which largely offset each other and render the total methylation levels unchanged. Further analysis revealed that the altered methylation patterns were meiotically heritable to at least the M2 generation but accompanied with further changes in each generation. The methylation changes and their heritability of the metastable epigenetic state were verified by bisulfite sequencing of portion of the retrotranspon, Tos17, an established locus for assessing DNA methylation liability in rice. Real-time PCR assay indicated that the expression of various methylation-related chromatin genes was perturbed, and a Pearson correlation analysis showed that many of these genes, especially two AGOs (AGO4-1 and AGO4-2), were significantly correlated with the methylation pattern alterations. In addition, excisions of a MITE transposon, mPing, occurred rampantly in the laser irradiated plants and their progenies. Together, our results indicate that heritable DNA methylation changes can be readily induced by low-dose laser irradiation, and which can be accompanied by transpostional activation of transposable elements. PMID:28377781

  15. Geoscience, Engineering, and Physics Opportunities at the China JinPing Underground Laboratory, its Extension, and at Other Sites > 2000 m

    NASA Astrophysics Data System (ADS)

    Wang, J. S.; Li, S.; Feng, X.

    2013-12-01

    The expansion of the China JinPing Laboratory (CJPL) is planned along a main branch of a bypass tunnel in the JinPing tunnel complex during 2013 -2015. This second phase of CJPL (CJPL-2) will have laboratory space increased from existing volume of nearly 2,000 m3 to approximately 80,000m3. In this presentation, we first review the geophysical and engineering findings during the originally tunnel excavations of the JingPing tunnel complexes which are substantially under overburdens from 2,000 to 2,500 m. Acoustic emissions associated with excavation disturbed zones and fracture openings in the excavation damaged zones were monitored before some sudden rock bust events were observed. The CJPL-2 offers opportunities to validate the rock burst modeling and prediction capabilities for other deep excavation studies. We also discuss the possibilities of other local, regional, and global monitoring of seismic-induced radon emission and electromagnetic monitoring studies, coupled process in situ measurements, and other experiments from the prospective of geoscience studies at depths over 2000 m. Geophysical and engineering opportunities were evaluated together with the physics experiments requirements in a 2015 town meeting associated with the 13th International Conference on Topics in Astroparticle and Underground Physics (TAUP). The main objective of CJPL-2 is to provide amber spaces needed worldwide for physics rare event detections that can be benefited to locate at CJPL-2, the currently deepest physics laboratory. Discussions the TAUP town meeting included one-ton expansions of current CJPL setups of Germanium detector in the China Darkmatter EXperiment (CDEX), two-phase Xenon detector of the PandiX experiment, other cryogenic dark matter detectors, superheated liquid detectors, scintillation solar neutrino detectors, neutrino-less double beta decay detectors, nuclear astrophysics synthesis accelerators, and other experimental and detector ideas.

  16. Chinese patent medicine Fei-Liu-Ping ointment as an adjunctive treatment for non-small cell lung cancer: protocol for a systematic review

    PubMed Central

    Zheng, Honggang; He, Shulin; Liu, Rui; Xu, Xinyao; Xu, Tao; Chen, Shuntai; Guo, Qiujun; Gao, Yebo; Hua, Baojin

    2017-01-01

    Introduction Fei-Liu-Ping ointment has been widely applied as adjunctive drug in the treatment of non-small cell lung cancer (NSCLC). However, there has been no systematic review of research findings regarding the efficacy of this treatment. Here, we provide a protocol for assessing the effectiveness and safety of Fei-Liu-Ping ointment in the treatment of NSCLC. Methods and analysis The electronic databases to be searched will include MEDLINE (PubMed), Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, Excerpt Medica Database (EMBASE), China National Knowledge Infrastructure (CNKI), China Scientific Journal Database (VIP), Wanfang Database and Chinese Biomedical Literature Database (CBM). Papers in English or Chinese published from inception to 2016 will be included without any restrictions. We will conduct a meta-analysis of randomised controlled trial if possible. The therapeutic effects according to the standard for treatment of solid tumours by the WHO and the quality of life as evaluated by Karnofsky score and weight will be applied as the primary outcomes. We will also evaluate the data synthesis and risk of bias using Review Manager 5.3 software. Dissemination The results of this review will offer implications for the use of Fei-Liu-Ping ointment as an adjunctive treatment for NSCLC. This knowledge will inform recommendations by surgeons and researchers who are interested in the treatment of NSCLC. The results of this systematic review will be disseminated through presentation at a conference and publication of the data in a peer-reviewed journal. Trial registration number PROSPERO CRD42016036911. PMID:28093444

  17. With or without "Li."

    ERIC Educational Resources Information Center

    Wang, Mingquan

    1990-01-01

    Demonstrates how the important distinction between the locative and nonlocative implication of a noun is essential for the presence of the Chinese locative particle "li," identifying groups of nouns that can not take the particle, nouns that optionally use the particle, and nouns that must use the particle. (CB)

  18. Line Intercept (LI)

    Treesearch

    John F. Caratti

    2006-01-01

    The FIREMON Line Intercept (LI) method is used to assess changes in plant species cover for a macroplot. This method uses multiple line transects to sample within plot variation and quantify statistically valid changes in plant species cover and height over time. This method is suited for most forest and rangeland communities, but is especially useful for sampling...

  19. Mass of Li11 from the H1(Li11,Li9)H3 reaction

    NASA Astrophysics Data System (ADS)

    Roger, T.; Savajols, H.; Tanihata, I.; Mittig, W.; Alcorta, M.; Bandyopadhyay, D.; Bieri, R.; Buchmann, L.; Caamaño, M.; Davids, B.; Galinski, N.; Gallant, A.; Howell, D.; Kanungo, R.; Mills, W.; Mythili, S.; Notani, M.; Openshaw, R.; Padilla-Rodal, E.; Roussel-Chomaz, P.; Ruprecht, G.; Savard, G.; Sheffer, G.; Shotter, A. C.; Trinczek, M.; Walden, P.

    2009-03-01

    The mass of Li11 has been determined from Q-value measurements of the H1(Li11,Li9)H3 reaction. The experiment was performed at TRIUMF laboratory with the GANIL active target MAYA. Energy-energy and angle-angle kinematics reconstruction give a Q value of 8.119(22) MeV for the reaction. The derived Li11 two-neutron separation energy is S2n=363(22) keV.

  20. Excited states in ^9Li from d(^8Li,p)^9Li

    NASA Astrophysics Data System (ADS)

    Rehm, K. E.; Greene, J. P.; Henderson, D. J.; Janssens, R. V. F.; Jiang, C. L.; Moore, E. F.; Pardo, R. C.; Peterson, D.; Pieper, S. C.; Savard, G.; Schiffer, J. P.; Sinha, S.; Tang, X.; Wiringa, R. W.; Wuosmaa, A. H.; Jisonna, L.; Segel, R. E.; Paul, M.

    2004-10-01

    We have studied levels in ^9Li from the d(^8Li,p)^9Li reaction using an unstable ^8Li beam produced at the ATLAS "in-flight" production facility at Argonne National Laboratory. The ^8Li beam bombarded a solid CD2 target. Protons from the d(^8Li,p)^9Li reaction were detected at backward angles in the laboratory using segmented silicon detectors, in coincidence with forward scattered ^7,8,9Li ions. The neutron spectroscopic factors determined from the d(^8Li,p)^9Li reaction can be used as a sensitive test for modern calculations of the structure of ^9Li. Experimental proton angular distributions for low-lying levels in ^9Li will be presented and compared with theoretical predictions. Work Supported by the U. S. DOE, Office of Nuclear Physics, Contract numbers W-31-109-ENG-38 (ANL), DE-FG02-04R41320 (WMU) and DE-FG02-98ER4106 (NWU), and the Faculty Research and Creative Activities Fund, Western Michigan University (WMU).

  1. Li-Fraumeni syndrome.

    PubMed

    Ossa, Carlos Andrés; Molina, Gustavo; Cock-Rada, Alicia María

    2016-06-03

    The Li-Fraumeni syndrome is characterized clinically by the appearance of tumors in multiple organs generally at an early age. This hereditary condition is caused by germinal mutations in the TP53 gene, which codifies for the tumoural suppressor gene p53. We present the case of a patient aged 31 with clinical and molecular diagnosis of Li-Fraumeni syndrome who presented two synchronous tumors: a leiomyosarcoma on the forearm and a phyllodes breast tumour. She had a family history of cancer, including a son diagnosed with a cortical adrenal carcinoma when he was three years old, who died at five from the disease. Furthermore, her maternal grandmother and great-grandmother died of stomach cancer at 56 and 60 years old, respectively, while her other great-grandmother and a great aunt presented with breast cancer at the ages of 60 and 40, respectively. After genetic counseling, complete sequencing and analysis of duplications and deletions in the TP53 gene were ordered prior to diagnosis. The molecular analysis of a DNA sample taken from peripheral blood lymphocytes revealed the germinal mutation c.527G>T (p.Cys176Phe) on exon 5 of the TP53 gene, a deleterious mutation described previously in tumoural tissues. To our knowledge, this is the first published case in Colombia of Li-Fraumeni syndrome with confirmed molecular diagnosis. The diagnosis and management of Li-Fraumeni syndrome should be performed by a multidisciplinary team, and genetic counselling should be offered to patients and their relatives.

  2. 7Li NMR on Li intercalated carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Schmid, M.; Goze-Bac, C.; Mehring, M.; Roth, S.

    2005-09-01

    Solid state 7Li Nuclear Magnetic Resonance (NMR) measurements were performed on lithium intercalated single wall carbon nanotubes (SWNT). The temperature dependence of the static spectra, as well as the spin-lattice relaxation behavior of the intercalated Li nuclei reveal two coexisting kinds of Li intercalation sites. Our results can be interpreted in terms of a staging phenomenon similar to graphite intercalation compounds (GIC).

  3. Invariant-mass spectroscopy of 10Li and 11Li

    NASA Astrophysics Data System (ADS)

    Zinser, M.; Humbert, F.; Nilsson, T.; Schwab, W.; Simon, H.; Aumann, T.; Borge, M. J. G.; Chulkov, L. V.; Cub, J.; Elze, Th. W.; Emling, H.; Geissel, H.; Guillemaud-Mueller, D.; Hansen, P. G.; Holzmann, R.; Irnich, H.; Jonson, B.; Kratz, J. V.; Kulessa, R.; Leifels, Y.; Lenske, H.; Magel, A.; Mueller, A. C.; Münzenberg, G.; Nickel, F.; Nyman, G.; Richter, A.; Riisager, K.; Scheidenberger, C.; Schrieder, G.; Stelzer, K.; Stroth, J.; Surowiec, A.; Tengblad, O.; Wajda, E.; Zude, E.

    1997-02-01

    Break-up of secondary 11Li ion beams (280 MeV/nucleon) on C and Pb targets into 9Li and neutrons is studied experimentally. Cross sections and neutron multiplicity distributions are obtained, characterizing different reaction mechanisms. Invariant-mass spectroscopy for 11Li and 10Li is performed. The E1 strength distribution, deduced from electromagnetic excitation of 11Li up to an excitation energy of 4 MeV comprises ˜8% of the Thomas-Reiche-Kuhn energy-weighted sumrule strength. Two low-lying resonance-like structures are observed for 10Li at decay energies of 0.21(5) and 0.62(10) MeV, the former one carrying 26(10)% of the strength and likely to be associated with an s-wave neutron decay. A strong di-neutron correlation in 11Li can be discarded. Calculations in a quasi-particle RPA approach are compared with the experimental results for 10Li and 11Li.

  4. Timing of metamorphism of the Lansang gneiss and implications for left-lateral motion along the Mae Ping (Wang Chao) strike-slip fault, Thailand

    NASA Astrophysics Data System (ADS)

    Palin, R. M.; Searle, M. P.; Morley, C. K.; Charusiri, P.; Horstwood, M. S. A.; Roberts, N. M. W.

    2013-10-01

    The Mae Ping fault (MPF), western Thailand, exhibits dominantly left-lateral strike-slip motion and stretches for >600 km, reportedly branching off the right-lateral Sagaing fault in Myanmar and extending southeast towards Cambodia. Previous studies have suggested that the fault assisted the large-scale extrusion of Sundaland that occurred during the Late Eocene-Early Oligocene, with a geological offset of ˜120-150 km estimated from displaced high-grade gneisses and granites of the Chiang Mai-Lincang belt. Exposures of high-grade orthogneiss in the Lansang National Park, part of this belt, locally contain strong mylonitic textures and are bounded by strike-slip ductile shear zones and brittle faults. Geochronological analysis of monazite from a sample of sheared biotite-K-feldspar orthogneiss suggests two episodes of crystallization, with core regions documenting Th-Pb ages between c. 123 and c. 114 Ma and rim regions documenting a significantly younger age range between c. 45-37 Ma. These data are interpreted to represent possible magmatic protolith emplacement for the Lansang orthogneiss during the Early Cretaceous, with a later episode of metamorphism occurring during the Eocene. Textural relationships provided by in situ analysis suggest that ductile shearing along the MPF occurred during the latter stages of, or after, this metamorphic event. In addition, monazite analyzed from an undeformed garnet-two-mica granite dyke intruding metamorphic units at Bhumipol Lake outside of the Mae Ping shear zone produced a Th-Pb age of 66.2 ± 1.6 Ma. This age is interpreted to date the timing of dyke emplacement, implying that the MPF cuts through earlier formed magmatic and high-grade metamorphic rocks. These new data, when combined with regional mapping and earlier geochronological work, show that neither metamorphism, nor regional cooling, was directly related to strike-slip motion.

  5. Calorimetric studies of Cu-Li, Li-Sn, and Cu-Li-Sn.

    PubMed

    Fürtauer, S; Tserenjav, E; Yakymovych, A; Flandorfer, H

    2013-06-01

    Integral molar enthalpies of mixing were determined by drop calorimetry for Cu-Li-Sn at 1073 K along five sections xCu/xSn ≈ 1:1, xCu/xSn ≈ 2:3, xCu/xSn ≈ 1:4, xLi/xSn ≈ 1:1, and xLi/xSn ≈ 1:4. The integral and partial molar mixing enthalpies of Cu-Li and Li-Sn were measured at the same temperature, for Li-Sn in addition at 773 K. All binary data could be described by Redlich-Kister-polynomials. Cu-Li shows an endothermic mixing effect with a maximum in the integral molar mixing enthalpy of ∼5300 J · mol(-1) at xCu = 0.5, Li-Sn an exothermic minimum of ∼ -37,000 J · mol(-1) at xSn ∼ 0.2. For Li-Sn no significant temperature dependence between 773 K and 1073 K could be deduced. Our measured ternary data were fitted on the basis of an extended Redlich-Kister-Muggianu model for substitutional solutions. Additionally, a comparison of these results to the extrapolation model of Chou is given.

  6. Lithium salts for advanced lithium batteries: Li-metal, Li-O2, and Li-S

    SciTech Connect

    Younesi, Reza; Veith, Gabriel M.; Johansson, Patrik; Edstrom, Kristina; Vegge, Tejs

    2015-06-01

    Presently lithium hexafluorophosphate (LiPF6) is the dominant Li-salt used in commercial rechargeable lithium-ion batteries (LIBs) based on a graphite anode and a 3-4 V cathode material. While LiPF6 is not the ideal Li-salt for every important electrolyte property, it has a uniquely suitable combination of properties (temperature range, passivation, conductivity, etc.) rendering it the overall best Li-salt for LIBs. However, this may not necessarily be true for other types of Li-based batteries. Indeed, next generation batteries, for example lithium-metal (Li-metal), lithium-oxygen (Li-O2), and lithium sulphur (Li-S), require a re-evaluation of Li-salts due to the different electrochemical and chemical reactions and conditions within such cells. Furthermore, this review explores the critical role Li-salts play in ensuring in these batteries viability.

  7. Lithium salts for advanced lithium batteries: Li-metal, Li-O2, and Li-S

    DOE PAGES

    Younesi, Reza; Veith, Gabriel M.; Johansson, Patrik; ...

    2015-06-01

    Presently lithium hexafluorophosphate (LiPF6) is the dominant Li-salt used in commercial rechargeable lithium-ion batteries (LIBs) based on a graphite anode and a 3-4 V cathode material. While LiPF6 is not the ideal Li-salt for every important electrolyte property, it has a uniquely suitable combination of properties (temperature range, passivation, conductivity, etc.) rendering it the overall best Li-salt for LIBs. However, this may not necessarily be true for other types of Li-based batteries. Indeed, next generation batteries, for example lithium-metal (Li-metal), lithium-oxygen (Li-O2), and lithium sulphur (Li-S), require a re-evaluation of Li-salts due to the different electrochemical and chemical reactions andmore » conditions within such cells. Furthermore, this review explores the critical role Li-salts play in ensuring in these batteries viability.« less

  8. 6Li from Solar Flares.

    PubMed

    Ramaty; Tatischeff; Thibaud; Kozlovsky; Mandzhavidze

    2000-05-10

    By introducing a hitherto ignored 6Li producing process, due to accelerated 3He reactions with 4He, we show that accelerated particle interactions in solar flares produce much more 6Li than 7Li. By normalizing our calculations to gamma-ray data, we demonstrate that the 6Li produced in solar flares, combined with photospheric 7Li, can account for the recently determined solar wind lithium isotopic ratio, obtained from measurements in lunar soil, provided that the bulk of the flare-produced lithium is evacuated by the solar wind. Further research in this area could provide unique information on a variety of problems, including solar atmospheric transport and mixing, solar convection and the lithium depletion issue, and solar wind and solar particle acceleration.

  9. Recovery of Li from alloys of Al- Li and Li- Al using engineered scavenger compounds

    DOEpatents

    Riley, W. D.; Jong, B. W.; Collins, W. K.; Gerdemann, S. J.

    1994-01-01

    A method of producing lithium of high purity from lithium aluminum alloys using an engineered scavenger compound, comprising: I) preparing an engineered scavenger compound by: a) mixing and heating compounds of TiO2 and Li2CO3 at a temperature sufficient to dry the compounds and convert Li.sub.2 CO.sub.3 to Li.sub.2 O; and b) mixing and heating the compounds at a temperature sufficient to produce a scavenger Li.sub.2 O.3TiO.sub.2 compound; II) loading the scavenger into one of two electrode baskets in a three electrode cell reactor and placing an Al-Li alloy in a second electrode basket of the three electrode cell reactor; III) heating the cell to a temperature sufficient to enable a mixture of KCl-LiCl contained in a crucible in the cell to reach its melting point and become a molten bath; IV) immersing the baskets in the bath until an electrical connection is made between the baskets to charge the scavenger compound with Li until there is an initial current and voltage followed by a fall off ending current and voltage; and V) making a connection between the basket electrode containing engineered scavenger compound and a steel rod electrode disposed between the basket electrodes and applying a current to cause Li to leave the scavenger compound and become electrodeposited on the steel rod electrode.

  10. Electron-impact Ionization Of Li2 And Li+2

    SciTech Connect

    Colgan, James P

    2008-01-01

    Electron-impact ionization cross sections for Li{sub 2} and Li{sup +}{sub 2} are calculated using a configuration-average distorted-wave method. Bound orbitals for the molecule and its ions are calculated using a single configuration self-consistent field method based on a linear combination of Slater-type orbitals. The bound orbitals are transformed onto a two-dimensional lattice ({tau}, {theta}), which is variable in the radial coordinate and constant in the angular coordinate, from which Hartree with local exchange potentials are constructed. The single particle Schrodinger equation is then solved for continuum distorted-waves with S-matrix boundary conditions. Total ionization cross sections for Li{sub 2} at an equilibrium internuclear separation of R = 5.0 and for Li{sup +}{sub 2} at an equilibrium internuclear separation of R = 5.9 are presented.

  11. Li-Vacancy Ordering in LiBC Phase

    NASA Astrophysics Data System (ADS)

    Gungor, Ebru; Ozdas, Engin

    2006-03-01

    The discovery of a phonon mediated superconductivity in MgB2 with a Tc of 40 K has accelarated the scientific interest in similar layered compounds and the electronic band structure calculations showed that the high-Tc superconductivity is possible for the hole-doped layered lithium borocarbide, LixBC [1,2]. However, the superconducting features for Li off-stoichiometric borocarbide compounds have not been observed in any experimental studies, because of the difficulties in the sample preparation. In this work, the effects of synthesis conditions on the structure of LixBC samples with the different Li-stoichiometries and the phase stability were investigated. The structural studies showed that the intercalation process has a staging behaviour as Li intercalated graphite and a novel Li vacancy ordered structure for off-stoichiometric LixBC phases. [1] Rosner H.et al., PRL 88, 12 (2002) [2] Dewhurst et al., PRB 68, 020504(R) (2003)

  12. Outgassing in the LiD/LiOH System

    SciTech Connect

    Schildbach, M; Siekhaus, W; Dinh, L; McLean II, W

    2003-10-17

    Temperature programmed decomposition (TPD), scanning electron microscopy (SEM) and x-ray diffraction (XRD) were performed on lithium hydroxide (LiOH) polycrystallites and LiD/LiOH composite nanocrystals. Our studies revealed that LiOH grains are thermally decomposed into Li{sub 2}O, releasing water, following a three dimensional phase boundary movement from the surface inward. The rate of H{sub 2}O released is controlled by a rate constant that is expressed as: d{alpha}/dt ={upsilon}.e {sup -E/RT}.f({alpha}) where t is time; {alpha} is the reacted fraction (0 to 1); {upsilon} is the pre-exponential factor which includes many constants describing the initial state of the sample such as three dimensional shape factors of initial particles, molecular mass, density, stoichiometric factors of chemical reaction, active surface and number of lattice imperfections, and so forth; E is the activation energy for the rate controlling process, R is the gas molar constant, and f({alpha}) is an analytical function which is determined by the rate-limiting reaction mechanism (random nucleation, diffusion, phase boundary motion, etc.). Due to fewer neighboring bonds at the surface, surface lithium hydroxide decomposes at low activation energies of {approx} 86-92 kJ/mol with corresponding pre-exponential factors of {approx} 2.7 x 10{sup 6}-1.2 x 10{sup 7} s{sup -1}. Near-surface hydroxide, having bonding much like bulk hydroxide but experiencing more stress/strain, decomposes at activation energies of {approx} 89-108 kJ/mol with corresponding pre-exponential factors of {approx} 9.5 x 10{sup 5}-9.3 x 10{sup 7}s{sup -1}. Bulk lithium hydroxide, however, decomposes at higher activation energies of {approx} 115-142 kJ/mol with corresponding pre-exponential factors of {approx} 4.8 x 10{sup 6}-1.2 x 10{sup 9} s{sup -1}. Bulk lithium hydroxide is very stable if stored at room temperature. However, lithium hydroxide molecules at or near the surface of the grains slowly decompose, in a vacuum

  13. Concave binding of cationic Li to quadrannulene.

    PubMed

    Dang, Jing-Shuang; Wang, Wei-Wei; Zhao, Xiang; Nagase, Shigeru

    2017-08-09

    Binding of Li(+) to quadrannulene and its influence on buckybowl functionalization are introduced. The concave-trapped Li(+) acts as a Lewis acid and the rate of Diels-Alder cycloaddition is enhanced 10(8) times. A sandwiched bowl-Li(+)-bowl structure is stabilized via concave-cation-convex interactions, indicating the promoted role of Li(+) in buckybowl assembly.

  14. Li+ ionic conductivities and diffusion mechanisms in Li-based imides and lithium amide.

    PubMed

    Li, Wen; Wu, Guotao; Xiong, Zhitao; Feng, Yuan Ping; Chen, Ping

    2012-02-07

    In this study, both experimental ionic conductivity measurements and the first-principles simulations are employed to investigate the Li(+) ionic diffusion properties in lithium-based imides (Li(2)NH, Li(2)Mg(NH)(2) and Li(2)Ca(NH)(2)) and lithium amide (LiNH(2)). The experimental results show that Li(+) ions present superionic conductivity in Li(2)NH (2.54 × 10(-4) S cm(-1)) and moderate ionic conductivity in Li(2)Ca(NH)(2) (6.40 × 10(-6) S cm(-1)) at room temperature; while conduction of Li(+) ions is hardly detectable in Li(2)Mg(NH)(2) and LiNH(2) at room temperature. The simulation results indicate that Li(+) ion diffusion in Li(2)NH may be mediated by Frenkel pair defects or charged vacancies, and the diffusion pathway is more likely via a series of intermediate jumps between octahedral and tetrahedral sites along the [001] direction. The calculated activation energy and pre-exponential factor for Li(+) ion conduction in Li(2)NH are well comparable with the experimentally determined values, showing the consistency of experimental and theoretical investigations. The calculation of the defect formation energy in LiNH(2) reveals that Li defects are difficult to create to mediate the Li(+) ion diffusion, resulting in the poor Li(+) ion conduction in LiNH(2) at room temperature.

  15. Polymorphism of LiAg

    NASA Astrophysics Data System (ADS)

    Pavlyuk, V. V.; Dmytriv, G. S.; Tarasiuk, I. I.; Chumak, I. V.; Pauly, H.; Ehrenberg, H.

    2010-02-01

    A phase transition from the cubic CsCl-type structure (Pm-3m space group) into a tetragonal UPb-type structure (I4 1/amd) is observed for the LiAg binary compound at ambient conditions. The crystal structure of the tetragonal modification of the LiAg binary compound was solved by direct methods in SHELXS on the base of structure factors which were extracted from a powder diffraction pattern and refined by SHELXL and the Rietveld method ( a = 3.9605(1), c = 8.2825(2) Å, Bragg R-factor = 4.81, Rf-factor = 4.87). Elevated temperatures and/or a small Li-excess versus the equimolar composition favour the cubic structure whereas ambient and lower temperatures and/or a small Li-deficiency stabilize the tetragonal structure. This reconstructive transition is reversible but proceeds slowly.

  16. Anion Coordination Interactions in Solvates with the Lithium Salts LiDCTA and LiTDI

    SciTech Connect

    McOwen, Dennis W.; Delp, Samuel A.; Paillard, Elie; Herriot, Cristelle; Han, Sang D.; Boyle, Paul D.; Sommer, Roger D.; Henderson, Wesley A.

    2014-04-17

    Lithium 4,5-dicyano-1,2,3-triazolate (LiDCTA) and lithium 2-trifluoromethyl-4,5-dicyanoimidazole (LiTDI) are two salts proposed for lithium battery electrolyte applications, but little is known about the manner in which the DCTA- and TDI- anions coordinate Li+ cations. To explore this in-depth, crystal structures are reported here for two solvates with LiDCTA: (G2)1:LiDCTA and (G1)1:LiDCTA with diglyme and monoglyme, respectively, and seven solvates with LiTDI: (G1)2:LiTDI, (G2)2:LiTDI, (G3)1:LiTDI, (THF)1:LiTDI, (EC)1:LiTDI, (PC)1:LiTDI and (DMC)1/2:LiTDI with monoglyme, diglyme, triglyme, tetrahydrofuran, ethylene carbonate, propylene carbonate and dimethyl carbonate, respectively. These latter solvate structures are compared with the previously reported acetonitrile (AN)2:LiTDI structure. The solvates indicate that the LiTDI salt is much less associated than the LiDCTA salt and that the ions in LiTDI, when aggregated in solvates, have a very similar TDI-...Li+ cation mode of coordination through both the anion ring and cyano nitrogen atoms. Such coordination facilitates the formation of polymeric ion aggregates, instead of dimers. Insight into such ion speciation is instrumental for understanding the electrolyte properties of aprotic solvent mixtures with these salts.

  17. Electrolytic LiCl precipitation from LiCl-KCl melt in porous Li-Al anodes

    NASA Astrophysics Data System (ADS)

    Vallet, C. E.; Heatherly, D. E.; Heatherly, L., Jr.; Braunstein, J.

    1983-12-01

    Composition gradients such as those predicted to occur during discharge of porous Li-Al negative electrodes of Li/S batteries with LiCl-KCl eutectic electrolyte were generated and measured in the LiCl-KCl anolyte of an electrolysis cell with Li-Al electrodes. Precipitation of lithium chloride during electrolysis was observed by two-dimensional scanning of electrolyte composition in the front part of quenched porous Li-Al anode sections using SEM/EDX. The distribution of sites of increased or decreased LiCl concentration, LiCl saturation and precipitation was mapped. Cathodic regions were observed near the cell walls. Preliminary results of analysis by Auger spectroscopy confirm LiCl precipitation in the porous anode.

  18. Electrolytic LiCl precipitation from LiCl-KCl melt in porous Li-Al anodes

    SciTech Connect

    Vallet, C.E.; Heatherly, D.E.; Heatherly, L. Jr.; Braunstein, J.

    1983-12-01

    Composition gradients such as those predicted to occur during discharge of porous Li-Al negative electrodes of Li/S batteries with LiCl-KCl eutectic electrolyte were generated and measured in the LiCl-KCl anolyte of an electrolysis cell with Li-Al electrodes. Precipitation of lithium chloride during electrolysis was observed by two-dimensional scanning of electrolyte composition in the front part of quenched porous Li-Al anode sections using SEM/EDX. The distribution of sites of increased or decreased LiCl concentration, LiCl saturation and precipitation was mapped. Cathodic regions were observed near the cell walls. Preliminary results of analysis by Auger spectroscopy confirm LiCl precipitation in the porous anode. 16 references, 7 figures, 1 table.

  19. Metallic Li colloids studied by Li-7 MAS NMR in electron-irradiated LiF

    NASA Astrophysics Data System (ADS)

    Zogal, O. J.; Beuneu, F.; Vajda, P.; Florian, P.; Massiot, D.

    Li-7 MAS NMR spectra of 2.5 MeV electron-irradiated LiF crystals have been measured in a field of 9.4 T. Besides the resonance line of the ionic compound, a second well-separated spectrum is observed in the region of the Knight shift value for metallic lithium. At room temperature, the latter can be decomposed into two components with different Knight shift and linewidth values. When the temperature is increased, line narrowing takes place at first, indicating shortening of correlation times for self-diffusion, independently in both components. Above 370 K, both lines broaden and approach each other before collapsing into a single line. The high ppm component disappears after crossing the melting temperature of metallic lithium (454 K). The two lines are attributed to different types of metallic Li: one to bulk-like metal, the other to Li present initially under pressure and relaxing to the former under thermal treatment.

  20. Comparative investigation of concentrations of major and trace elements in organic and conventional Danish agricultural crops. 1. Onions (Allium cepa Hysam) and peas (Pisum sativum ping pong).

    PubMed

    Gundersen, V; Bechmann, I E; Behrens, A; Stürup, S

    2000-12-01

    210 samples of onions (Allium cepa Hysam) from 11 conventionally and 10 organically cultivated sites and 190 samples of peas (Pisum sativum Ping Pong) from 10 conventionally and 9 organically cultivated sites in Denmark were collected and analyzed for 63 and 55 major and trace elements, respectively, by high-resolution inductively coupled plasma mass spectrometry. Sampling, sample preparation, and analysis of the samples were performed under carefully controlled contamination-free conditions. Comparative statistical tests of the element concentration mean values for each site show significantly (p < 0.05) different levels of Ca, Mg, B, Bi, Dy, Eu, Gd, Lu, Rb, Sb, Se, Sr, Ti, U, and Y between the organically and conventionally grown onions and significantly (p < 0.05) different levels of P, Gd, and Ti between the organically and conventionally grown peas. Principal component analysis (PCA) applied to the 63 elements measured in the individual onion samples from the 21 sites split up the sites into two groups according to the cultivation method when the scores of the first and third principal components were plotted against each other. Correspondingly, for peas, a PCA applied to the 55 elements measured as mean values for each site split up the 19 sites into two groups according to the cultivation method when the scores of the third and fourth principal component were plotted against each other. The methodology may be used as authenticity control for organic cultivation after further method development.

  1. Nernst-ping-pong model for evaluating the effects of the substrate concentration and anode potential on the kinetic characteristics of bioanode.

    PubMed

    Peng, Sikan; Liang, Da-Wei; Diao, Peng; Liu, Yanyan; Lan, Fei; Yang, Yuhan; Lu, Shanfu; Xiang, Yan

    2013-05-01

    Understanding the electron-transfer mechanism and kinetic characteristics of bioanodes is greatly significant to enhance the electron-generating efficiencies in bioelectrochemical systems (BESs). A Nernst-ping-pong model is proposed here to investigate the kinetics and biochemical processes of bioanodes in a microbial electrolysis cell. This model can accurately describe the effects of the substrate (including substrate inhibition) and the anode potential on the current of bioanodes. Results show that the half-wave potential positively shifts as the substrate concentration increases, indicating that the rate-determining steps of anodic processes change from substrate oxidation to intracellular electron transport reaction. The anode potential has negligible effects on the enzymatic catalysis of anodic microbes in the range of -0.25 V to +0.1 V vs. a saturated calomel electrode. It turns out that to reduce the anodic energy loss caused by overpotential, higher substrate concentrations are preferred, if the substrate do not significantly and adversely affect the output current.

  2. Aub and Ago3 are recruited to nuage through two mechanisms to form a ping-pong complex assembled by Krimper

    PubMed Central

    Webster, Alexandre; Li, Sisi; Hur, Junho K.; Wachsmuth, Malte; Bois, Justin S.; Perkins, Edward M.; Patel, Dinshaw J.; Aravin, Alexei A.

    2015-01-01

    In Drosophila, two Piwi proteins, Aubergine (Aub) and Argonaute-3 (Ago3) localize to perinuclear ‘nuage’ granules and use guide piRNAs to target and destroy transposable element transcripts. We find that Aub and Ago3 are recruited to nuage by two different mechanisms. Aub requires a piRNA guide for nuage recruitment, indicating that its localization depends on recognition of RNA targets. Ago3 is recruited to nuage independently of a piRNA cargo and relies on interaction with Krimper, a stable component of nuage that is able to aggregate in the absence of other nuage proteins. We show that Krimper interacts directly with Aub and Ago3 to coordinate the assembly of the ping-pong piRNA processing (4P) complex. Symmetrical dimethylated arginines are required for Aub to interact with Krimper, but are dispensable for Ago3 to bind Krimper. Our study reveals a multi-step process responsible for the assembly and function of nuage complexes in piRNA-guided transposon repression. PMID:26295961

  3. Yu Ping Feng San, an Ancient Chinese Herbal Decoction Containing Astragali Radix, Atractylodis Macrocephalae Rhizoma and Saposhnikoviae Radix, Regulates the Release of Cytokines in Murine Macrophages

    PubMed Central

    Du, Crystal Y. Q.; Choi, Roy C. Y.; Zheng, Ken Y. Z.; Dong, Tina T. X.; Lau, David T. W.; Tsim, Karl W. K.

    2013-01-01

    Yu Ping Feng San (YPFS), a Chinese herbal decoction, is composed of Astragali Radix (AR; Huangqi), Atractylodis Macrocephalae Rhizoma (AMR; Baizhu) and Saposhnikoviae Radix (SR; Fangfeng) in a weight ratio of 1∶2∶1. Clinically, YPFS has been widely used to regulate immune functions; however, the action mechanism of it is not known. Here, we addressed this issue by providing detail analyses of chemical and biological properties of YPFS. By using rapid resolution liquid chromatography coupled with mass spectrometry, fifteen chemicals deriving from different herbs of YPFS were determined, and which served as a control for the standardization of the herbal extract of YPFS. In general, the amounts of chosen chemical markers were higher in a preparation of YPFS as compared to that of single herb or two-herb compositions. In order to reveal the immune functions of YPFS, the standardized extract was applied onto cultured murine macrophages. The treatment of YPFS stimulated the mRNA and protein expressions of pro-inflammatory cytokines via activation of NF-κB by enhancing IκBα degradation. In contrast, the application of YPFS suppressed the expressions of pro-inflammatory cytokines significantly in the lipopolysaccharide (LPS)-induced chronic inflammation model. In addition, YPFS could up regulate the phagocytic activity in cultured macrophages. These results therefore supported the bi-directional immune-modulatory roles of YPFS in regulating the releases of cytokines from macrophages. PMID:24244327

  4. Histone-derived piRNA biogenesis depends on the ping-pong partners Piwi5 and Ago3 in Aedes aegypti.

    PubMed

    Girardi, Erika; Miesen, Pascal; Pennings, Bas; Frangeul, Lionel; Saleh, Maria-Carla; van Rij, Ronald P

    2017-01-23

    The piRNA pathway is of key importance in controlling transposable elements in most animal species. In the vector mosquito Aedes aegypti, the presence of eight PIWI proteins and the accumulation of viral piRNAs upon arbovirus infection suggest additional functions of the piRNA pathway beyond genome defense. To better understand the regulatory potential of this pathway, we analyzed in detail host-derived piRNAs in A. aegypti Aag2 cells. We show that a large repertoire of protein-coding genes and non-retroviral integrated RNA virus elements are processed into genic piRNAs by different combinations of PIWI proteins. Among these, we identify a class of genes that produces piRNAs from coding sequences in an Ago3- and Piwi5-dependent fashion. We demonstrate that the replication-dependent histone gene family is a genic source of ping-pong dependent piRNAs and that histone-derived piRNAs are dynamically expressed throughout the cell cycle, suggesting a role for the piRNA pathway in the regulation of histone gene expression. Moreover, our results establish the Aag2 cell line as an accessible experimental model to study gene-derived piRNAs.

  5. Yu Ping Feng San reverses cisplatin-induced multi-drug resistance in lung cancer cells via regulating drug transporters and p62/TRAF6 signalling

    PubMed Central

    Lou, Jian-Shu; Yan, Lu; Bi, Cathy W. C.; Chan, Gallant K. L.; Wu, Qi-Yun; Liu, Yun-Le; Huang, Yun; Yao, Ping; Du, Crystal Y. Q.; Dong, Tina T. X.; Tsim, Karl W. K.

    2016-01-01

    Yu Ping Feng San (YPFS), an ancient Chinese herbal decoction composed of Astragali Radix, Atractylodis Macrocephalae Rhizoma and Saposhnikoviae Radix, has been used in the clinic for treating immune deficiency. In cancer therapy, YPFS is being combined with chemotherapy drugs to achieve improved efficacy; however, scientific evidence to illustrate this combination effect is lacking. The present study aims to demonstrate the anti-drug resistance of YPFS in cisplatin (DDP)-resistant non-small cell lung cancer cells (A549/DDP). The application of YPFS exhibited a synergistic enhancement of DDP-induced cytotoxicity as well as of the apoptotic signalling molecules. DDP-induced expression of the multi-drug-resistance efflux transporters was markedly reduced in the presence of YPFS, resulting in a higher intracellular concentration of DDP. In addition, the application of YPFS increased DDP-induced ROS accumulation and MMP depletion, decreased p62/TRAF6 signalling in DDP-treated A549/DDP cells. The co-treatment of DDP and YPFS in tumour-bearing mice reduced the tumour size robustly (by more than 80%), which was much better than the effect of DDP alone. These results indicate that YPFS can notably improve the DDP-suppressed cancer effect, which may be a consequence of the elevation of intracellular DDP via the drug transporters as well as the down regulation of p62/TRAF6 signalling. PMID:27558312

  6. Li-6/Li-7, B-10/B-11, and Li-7/B-11/Si-28 individual IDPs

    NASA Technical Reports Server (NTRS)

    Xu, Y.-L.; Song, L.-G.; Zhang, Y.-X.; Fan, C.-Y.

    1994-01-01

    At the initial stage of the development of our solar system, the solar nebula is presumably composed of H-1, H-2, He-3, He-4, and Li-7, which were made during the Big Band, and C, N, O, . . ., which are products of nearby supernova explosions. Li-6 nuclei (together with about equal amounts of Li-7), Be-9, B-10, and B-11 were produced later by cosmic ray particles bombarding the local interstellar C, N, O, . . . nuclei before the nebula condensed to become the Sun and the planets. Thus, the ratio Li-6/Li-7 is a measure of the length of the early epoch of the solar system. In this paper we shall report the measurement of Li-7/Li-6, B-11/B-10, and Li-7/B-11/Si-28 of four IDP's obtained from Johnson Space Center and discuss the findings.

  7. Transport properties derived from ion-atom collisions: 6Li-6Li+ and 6Li-7Li+ Cases

    NASA Astrophysics Data System (ADS)

    Bouledroua, Moncef; Bouchelaghem, Fouzia; LPR Team

    2014-10-01

    This investigation treats quantum-mechanically the ion- atom collisions and computes the transport coefficients, such as the coefficients of mobility and diffusion. For the case of lithium, the calculations start by determining the gerade and ungerade potential curves through which ionic lithium approaches ground lithium. Then, by considering the isotopic effects and nuclear spins, the elastic and charge-transfer cross sections are calculated for the case of 6Li+and7Li+ colliding with 6Li. Finally, the temperature-dependent diffusion and mobility coefficients are analyzed, and the results are contrasted with those obtained from literature. The main results of this work have been recently published in. This work has been realized within the frames of the CNEPRU Project D01120110036 of the Algerian Ministry of Higher Education.

  8. Li2S Film Formation on Lithium Anode Surface of Li-S batteries.

    PubMed

    Liu, Zhixiao; Bertolini, Samuel; Balbuena, Perla B; Mukherjee, Partha P

    2016-02-01

    The precipitation of lithium sulfide (Li2S) on the Li metal anode surface adversely impacts the performance of lithium-sulfur (Li-S) batteries. In this study, a first-principles approach including density functional theory (DFT) and ab initio molecular dynamics (AIMD) simulations is employed to theoretically elucidate the Li2S/Li metal surface interactions and the nucleation and growth of a Li2S film on the anode surface due to long-chain polysulfide decomposition during battery operation. DFT analyses of the energetic properties and electronic structures demonstrate that a single molecule adsorption on Li surface releases energy forming chemical bonds between the S atoms and Li atoms from the anode surface. Reaction pathways of the Li2S film formation on Li metal surfaces are investigated based on DFT calculations. It is found that a distorted Li2S (111) plane forms on a Li(110) surface and a perfect Li2S (111) plane forms on a Li(111) surface. The total energy of the system decreases along the reaction pathway; hence Li2S film formation on the Li anode surface is thermodynamically favorable. The calculated difference charge density of the Li2S film/Li surface suggests that the precipitated film would interact with the Li anode via strong chemical bonds. AIMD simulations reveal the role of the anode surface structure and the origin of the Li2S formation via decomposition of Li2S8 polysulfide species formed at the cathode side and dissolved in the electrolyte medium in which they travel to the anode side during battery cycling.

  9. Implementing web-based ping-pong-type e-communication to enhance staff satisfaction, multidisciplinary cooperation, and clinical effectiveness: A SQUIRE-compliant quality-improving study.

    PubMed

    Yeh, Pei-Han; Hung, Shih-Kai; Lee, Moon-Sing; Chiou, Wen-Yen; Lai, Chun-Liang; Tsai, Wei-Ta; Hsieh, Hui-Ling; Shih, Yi-Ting; Chen, Liang-Cheng; Huang, Li-Wen; Lin, Yi-An; Lin, Po-Hao; Lin, Yung-Hsiang; Liu, Dai-Wei; Hsu, Feng-Chun; Tsai, Shiang-Jiun; Liu, Jia-Chi; Chung, En-Seu; Lin, Hon-Yi

    2016-11-01

    Frequent multidisciplinary communication is essential in conducting daily radiotherapy (RT) practice. However, traditional oral or paper-based communication has limitations. E-communication has been suggested, but its effects are still not well demarcated in the field of radiation oncology. In our web-based integrated information platform, we constructed a ping-pong-type e-communication function to transfer specific notations among multidisciplinary RT staffs. The purpose was to test whether applying this e-communication can increase effectiveness of multidisciplinary cooperation when compared with oral or paper-based practice. Staff satisfaction and clinical benefits were also demonstrated. A real-world quality-improving study was conducted in a large center of radiation oncology. Before and after applying multidisciplinary e-communication (from 2014 to 2015), clinical RT staffs were surveyed for their user experience and satisfaction (n = 23). For measuring clinical effectiveness, a secondary database of irradiated head and neck cancer patients was re-analyzed for comparing RT toxicities (n = 402). Applying ping-pong-type multidisciplinary reflective e-communication was the main intervention. For measuring staff satisfaction, eight domains were surveyed, such as timeliness, convenience, and completeness. For measuring clinical effectiveness of multidisciplinary cooperation, event rates of severe (i.e., grade 3-4) RT mucositis and dermatitis were recorded. Overall, when compared with oral communication only, e-communication demonstrated multiple benefits, particularly on notation-review convenience (2.00 ± 1.76 vs 9.19 ± 0.81; P < 0.0001).When compared with paper-based practice, e-communication showed statistically significant benefits on all eight domains, especially on notation-review convenience (5.05 ± 2.11 vs 9.19 ± 0.81; P < 0.0001) and convenience of feedback notation (4.81 ± 1.72 vs 8.76 ± 1.09; P < 0

  10. Effects of Li content on precipitation in Al-Cu-(Li)-Mg-Ag-Zr alloys

    SciTech Connect

    Huang, B.P.; Zheng, Z.Q.

    1998-01-06

    Although much attention has been paid to Al-Cu-Li-Mg-Ag-Zr alloys, there are sparse reports about the influence of Li on precipitation in these alloys. The aim of the present study is to determine the effects of Li on modifying precipitation in a baseline aluminum alloy 2195 and the accompanying variants with 0--1.6 wt.% Li.

  11. Li Anode Technology for Improved Performance

    NASA Technical Reports Server (NTRS)

    Chen, Tuqiang

    2011-01-01

    A novel, low-cost approach to stabilization of Li metal anodes for high-performance rechargeable batteries was developed. Electrolyte additives are selected and used in Li cell electrolyte systems, promoting formation of a protective coating on Li metal anodes for improved cycle and safety performance. Li batteries developed from the new system will show significantly improved battery performance characteristics, including energy/power density, cycle/ calendar life, cost, and safety.

  12. [Effects of saline-alkali stress on electrical impedance spectroscopy parameters and ion contents in shoots of Ping'ou hybrid hazelnut].

    PubMed

    Zhang, Li; Jia, Zhi-Guo; Ma, Qing-Hua; Zhang, Gang; Wang, Gui-Xi

    2014-11-01

    To study the adaptability to salt-alkaline stress of Ping'ou hybrid hazelnut, 'Liaozhen 3' shoots which were treated with three types of stress neutral NaCl, alkaline Na2CO3, and mixed salt-alkali, and the changes in electrical impedance spectroscopy (EIS) parameters and mineral ion contents were subsequently determined. The correlations between the EIS parameters and mineral ion contents were analyzed. The results showed that with the increasing level of NaCl, specific high- frequency resistance (r), specific low-frequency resistance ( r(l)), specific intracellular resistance (r(i)) and specific extracellular resistance (r(e)) of shoots decreased firstly, then increased, and finally decreased again. However, these parameters increased gradually with the increasing level of Na2CO3, while r(l) and r(e) decreased slowly in the mixed salt-alkali treatments. The Na+ contents of shoots increased significantly under the three salt-alkali stresses with the order of NaCl stress > mixed salt-alkali stress > Na2CO3 stress. Furthermore, Na2CO3 stress resulted in the decreases in the contents of three elements Zn, B and Ca. The significant negative correlation was found between the sum of five cations and four EIS parameters r(l), r(e), relaxation time (τ) , and distribution coefficient of relaxation time (ψ). The shoots of 'Liaozhen 3' might be tolerant of Na2CO3 stress of 200 mmol · L(-1), while they could be resistant to NaCl stress of 100-150 mmol · L(-1).

  13. Evolution of Orofacial Symptoms and Disease Progression in Idiopathic Parkinson's Disease: Longitudinal Data from the Jönköping Parkinson Registry

    PubMed Central

    Skogar, Örjan; Lökk, Johan

    2017-01-01

    Background Orofacial symptoms are common in Parkinson's disease (PD) both as initial manifestations and late markers of disease complications. We aimed to investigate the evolution of orofacial manifestations and their prognostic value throughout PD progression. Methods Data was obtained from “Jönköping Parkinson Registry” database on routine care visits of 314 people with idiopathic PD in southern Sweden. Information on baseline symptomatology, orofacial features, UPDRS, and medications was recorded at baseline and during each follow-up visit within an average of 4.2 (range: 1–12) years. Results Hypomimia, affected speech, drooling, and impaired swallowing were present in 37.3%/91.6%, 14.1%/65.5%, 11.7%/55.3%, and 10.2%/34.5% at baseline/follow-up, respectively. Male sex [OR = 2.4 (95% CI: 1.0–5.9)], UPDRS motor scores [OR = 1.2 (95% CI: 1.1–1.3)], dominant rigidity [OR = 5.2 (95% CI: 1.4–19.1)], and autonomic disturbance [OR = 3.4 (95% CI: 1.1–10.9)] were risk factors for drooling. Individuals with more severe orofacial burden at baseline had shorter median time to develop UPDRS-Part III > 28 [3rd tertile = 4.7 yr, 2nd tertile = 6.2 yr, and 1st tertile = 7.8 yr; p = 0.014]. Conclusions Majority of people with PD manifest orofacial manifestations at either early or late stages of the disease. PD severity, symmetry of motor disturbances, and autonomic disorders correlate with orofacial symptoms. Individuals with more severe orofacial burden at baseline progressed faster to more advanced stages. PMID:28798882

  14. Evolution of Orofacial Symptoms and Disease Progression in Idiopathic Parkinson's Disease: Longitudinal Data from the Jönköping Parkinson Registry.

    PubMed

    Fereshtehnejad, Seyed-Mohammad; Skogar, Örjan; Lökk, Johan

    2017-01-01

    Orofacial symptoms are common in Parkinson's disease (PD) both as initial manifestations and late markers of disease complications. We aimed to investigate the evolution of orofacial manifestations and their prognostic value throughout PD progression. Data was obtained from "Jönköping Parkinson Registry" database on routine care visits of 314 people with idiopathic PD in southern Sweden. Information on baseline symptomatology, orofacial features, UPDRS, and medications was recorded at baseline and during each follow-up visit within an average of 4.2 (range: 1-12) years. Hypomimia, affected speech, drooling, and impaired swallowing were present in 37.3%/91.6%, 14.1%/65.5%, 11.7%/55.3%, and 10.2%/34.5% at baseline/follow-up, respectively. Male sex [OR = 2.4 (95% CI: 1.0-5.9)], UPDRS motor scores [OR = 1.2 (95% CI: 1.1-1.3)], dominant rigidity [OR = 5.2 (95% CI: 1.4-19.1)], and autonomic disturbance [OR = 3.4 (95% CI: 1.1-10.9)] were risk factors for drooling. Individuals with more severe orofacial burden at baseline had shorter median time to develop UPDRS-Part III > 28 [3rd tertile = 4.7 yr, 2nd tertile = 6.2 yr, and 1st tertile = 7.8 yr; p = 0.014]. Majority of people with PD manifest orofacial manifestations at either early or late stages of the disease. PD severity, symmetry of motor disturbances, and autonomic disorders correlate with orofacial symptoms. Individuals with more severe orofacial burden at baseline progressed faster to more advanced stages.

  15. Amicyanin transfers electrons from methylamine dehydrogenase to cytochrome c-551i via a ping-pong mechanism, not a ternary complex.

    PubMed

    Meschi, Francesca; Wiertz, Frank; Klauss, Linda; Cavalieri, Chiara; Blok, Anneloes; Ludwig, Bernd; Heering, Hendrik A; Merli, Angelo; Rossi, Gian Luigi; Ubbink, Marcellus

    2010-10-20

    The first crystal structure of a ternary redox protein complex was comprised of the enzyme methylamine dehydrogenase (MADH) and two electron transfer proteins, amicyanin and cytochrome c-551i from Paracoccus denitrificans [Chen et al. Science 1994, 264, 86-90]. The arrangement of the proteins suggested possible electron transfer from the active site of MADH via the amicyanin copper ion to the cytochrome heme iron, although the distance between the metals is large. We studied the interactions between these proteins in solution. A titration followed by NMR spectroscopy shows that amicyanin binds cytochrome c-551i. The interface comprises the hydrophobic and positive patches of amicyanin, not the binding site observed in the ternary complex. NMR experiments further show that amicyanin binds tightly to MADH with an interface that matches the one observed in the crystal structure and that mostly overlaps with the binding site for cytochrome c-551i. Upon addition of cytochrome c-551i, no changes in the NMR spectrum of MADH-bound amicyanin are observed, suggesting that a possible interaction of the cytochrome with the binary complex must be very weak, with a dissociation constant higher than 2 mM. Reconstitution of the entire redox chain in vitro demonstrates that amicyanin can react rapidly with cytochrome c-551i, but that association of amicyanin with MADH inhibits this reaction. It is concluded that electron transfer from MADH to cytochrome c-551i does not involve a ternary complex but occurs via a ping-pong mechanism in which amicyanin uses the same interface for the reactions with MADH and cytochrome c-551i.

  16. Reactions of metallic Li or LiC6 with organic solvents for lithium ion battery

    NASA Astrophysics Data System (ADS)

    Nakajima, Tsuyoshi; Hirobayashi, Yuki; Takayanagi, Yuki; Ohzawa, Yoshimi

    2013-12-01

    DSC (Differential Scanning Calorimetry) study has been made on the reactions of metallic Li or LiC6 with organic solvents for lithium ion battery. Ethylene carbonate (EC) more easily reacts with metallic Li and LiC6 than propylene carbonate (PC). This may be because formation of lithium alkyl carbonate is more difficult for PC than EC. On the other hand, diethyl carbonate (DEC), ethyl methyl carbonate (EMC) and dimethyl carbonate (DMC) react with Li in the same manner. Reactions of Li and LiC6 with organic solvents have been discussed based on the results of quantum calculation.

  17. Electrochemical Investigations of the Interface at Li/Li+ Ion Conducting Channel

    DTIC Science & Technology

    2006-10-04

    acetone consisting of LiBF4 as the supporting electrolyte. Unlike the powdery deposits of LiPc obtained by using tetrabutyl ammonium perchlorate (TBAP...as the supporting electrolyte, the deposits are adherent to the substrates when LiBF4 is used as the supporting electrolyte. Chemical oxidation of...Li2Pc by TBAP is shown to be detrimental for the formation of powdery electrodeposits of LiPc, whereas LiBF4 does not oxidize Li2Pc and therefore

  18. Li-S batteries: Firing for compactness

    NASA Astrophysics Data System (ADS)

    Li, Yanguang; Chen, Fengjiao

    2017-07-01

    Conventional Li-S batteries have a non-compact cathode structure containing low areal loading of active materials. Now, a strategy of burning Li foils in a CS2 vapour is presented, which leads to the formation of highly compact Li2S nanoparticles as a lithiated sulfur cathode, offering promising battery performance.

  19. The interstellar Li-7/Li-6 isotope ratio toward Zeta Ophiuchi and Zeta Persei

    NASA Technical Reports Server (NTRS)

    Meyer, David M.; Hawkins, Isabel; Wright, Edward L.

    1993-01-01

    High S/N, high-resolution observations of the interstellar Li absorption lines toward the stars Zeta Ophiuchi and Zeta Persei are reported. Li I line profiles indicate the presence of both the Li-7 and Li-6 doublets in these two sightlines. Best-fit values for the interstellar Li-7/Li-6 isotope ratio are 6.8 (+1.4/-1.7) towards Zeta Ophiuchi and 5.5 (+ 1.3/-1.1) toward Zeta Persei. Measurement of 6.8 (+1.4/-1.7) for the interstellar Li-7/Li-6 isotope ratio towards Zeta Ophiuchi does not support the lower limit of 25 determined by Ferlet and Dennefeld (1984). The current value of the interstellar Li-7/Li-6 isotope ratio is the result of various lithium production and destruction processes involving stars, cosmic rays, and the big bang.

  20. The Electrochemistry of Li-LiCl-Li2O Molten Salt Systems and the Role of Moisture

    NASA Astrophysics Data System (ADS)

    Gese, Natalie J.

    Uranium can be recovered from uranium-oxide (UO2) spent fuel through the combination of oxide reduction and electrorefining processes. During oxide reduction, the spent fuel is introduced to molten LiCl-Li 2O salt at 650°C, and the UO2 is reduced to uranium metal via two routes: (1) electrochemically, and (2) chemically by lithium metal (Li°) that is produced electrochemically. However, the hygroscopic nature of both LiCl and Li2O leads to the formation of LiOH, contributing hydroxyl anions (OH-), the reduction of which interferes with the Li° generation required for the chemical reduction of UO 2. In order for the oxide reduction process to be an effective method for the treatment of uranium-oxide fuel, the role of moisture in the LiCl-Li 2O system must be understood. The behavior of moisture in the LiCl-Li 2O molten-salt system was studied using cyclic voltammetry, chronopotentiometry, and chronoamperometry while reduction to hydrogen was confirmed with gas chromatography.

  1. Recovery of Li from alloys of Al-Li and Li-Al using engineered scavenger compounds

    SciTech Connect

    Riley, W.D.; Jong, B.W.; Collins, W.K.; Gerdemann, S.J.

    1992-01-01

    The invention relates to a process for obtaining Li metal selectively recovered from Li-Al or Al-Li alloy scrap by: (1) removing Li from aluminum-lithium alloys at temperatures between about 400 C-750 C in a molten salt bath of KC1-LiCl using lithium titanate (Li2O.3TiO2) as an engineered scavenger compound (ESC); and (2) electrodepositing of Li from the loaded ESC to a stainless steel electrode. By use of the second step, the ESC is prepared for reuse. A molten salt bath is required in the invention because of the inability of molten aluminum alloys to wet the ESC.

  2. /C Composite Cathode for Li Ion Battery

    NASA Astrophysics Data System (ADS)

    Wang, Shulan; Liu, Xuan; Li, Huiqing; Li, Li

    2014-12-01

    Li3V2(PO4)3/C composites were prepared at different temperatures and assembled as cathodes for Li ion batteries. Their structure and electrochemical properties were properly characterized. The internal and charge transfer resistance of the Li3V2(PO4)3/C cathodes were obtained by simulating the ac impedance spectra with equivalent circuits. The Li3V2(PO4)3/C composite sintered at 1123 K (850 °C) exhibits excellent electrochemical performances because of its smaller internal resistance and charge transfer resistance, as well as faster Li ion inserting/extracting rates.

  3. LiDy(PO3)4

    PubMed Central

    Chehimi-Moumen, Fathia; Férid, Mokhtar

    2008-01-01

    Single crystals of lithium dysprosium polyphosphate, LiDy(PO3)4, were prepared by the flux method. The atomic arrangement is built up by infinite (PO3)n chains extending along the b axis. Dy3+ and Li+ cations alternate in the middle of four such chains, with Dy⋯Li distances of 3.54 (1) and 3.48 (1) Å. The DyO8 dodeca­hedra and LiO4 tetra­hedra deviate significantly from the ideal geometry. Both Dy and Li occupy special positions (Wyckoff position 4e, site symmetry 2). PMID:21202729

  4. High accuracy ab initio studies of Li6+, Li6-, and three isomers of Li6

    NASA Astrophysics Data System (ADS)

    Temelso, Berhane; Sherrill, C. David

    2005-02-01

    The structures and energetics of Li6+, Li6- and three isomers of Li6 are investigated using the coupled-cluster singles, doubles and perturbative triples [CCSD(T)] method with valence and core-valence correlation consistent basis sets of double- to quadruple-ζ quality (cc-pVXZ and cc-pCVXZ, where X =D-Q). These results are compared with qualitatively different predictions by less reliable methods. Our results conclusively show that the D4h isomer is the global minimum structure for Li6. It is energetically favored over the C5v and D3h structures by about 5.1 and 7.1kcalmol-1, respectively, after the inclusion of the zero-point vibrational energy (ZPVE) correction. Our most accurate total atomization energies are 123.2, 117.6, and 115.7kcalmol-1 for the D4h, C5v, and D3h isomers, respectively. Comparison of experimental optical absorption spectra with our computed electronic spectra also indicate that the D4h isomer is indeed the most stable structure. The cation, anion, and some higher spin states are investigated using the less expensive cc-pCVDZ basis set. Adiabatic ionization energies and electron affinities are reported and compared with experimental values. Predictions of molecular properties are found to be sensitive to the basis set used and to the treatment of electron correlation.

  5. Pros and cons of vertical integration between clinical medicine and basic science within a problem-based undergraduate medical curriculum: examples and experiences from Linköping, Sweden.

    PubMed

    Dahle, L O; Brynhildsen, J; Behrbohm Fallsberg, M; Rundquist, I; Hammar, M

    2002-05-01

    Problem-based learning (PBL), combined with early patient contact, multiprofessional education and emphasis on development of communications skills, has become the basis for the medical curriculum at the Faculty of Health Sciences in Linköping (FHS), Sweden, which was started in 1986. Important elements in the curriculum are vertical integration, i.e. integration between the clinical and basic science parts of the curriculum and horizontal integration between different subject areas. This article discusses the importance of vertical integration in an undergraduate medical curriculum, according to experiences from the Faculty of Health Sciences in Linköping, and also give examples on how it has been implemented during the latest 15 years. Results and views put forward in published articles concerning vertical integration within undergraduate medical education are discussed in relation to the experiences in Linköping. Vertical integration between basic sciences and clinical medicine in a PBL setting has been found to stimulate profound rather than superficial learning, and thereby stimulates better understanding of important biomedical principles. Integration probably leads to better retention of knowledge and the ability to apply basic science principles in the appropriate clinical context. Integration throughout the whole curriculum entails a lot of time and work in respect of planning, organization and execution. The teachers have to be deeply involved and enthusiastic and have to cooperate over departmental borders, which may produce positive spin-off effects in teaching and research but also conflicts that have to be resolved. The authors believe vertical integration supports PBL and stimulates deep and lifelong learning.

  6. [Comparative study of theoretical literature on cold pathogenic disease in Wai tai mi yao fang (Arcane Essentials from the Imperial Library) and Tai ping sheng hui fang (Taiping Holy Prescriptions for Universal Relief)].

    PubMed

    Zhang, Huirui; Liang, Yongxuan

    2014-09-01

    In the Wai tai mi yao fang (Arcane Essentials from the Imperial Library) compiled in 752, its portion on cold pathogenic disorders embodies the achievements before the mid Tang Dynasty, whereas that in the Tai ping sheng hui fang (Taiping Holy Prescriptions for Universal Relief), compiled in 992 embodies those before the early Song Dynasty. Comparison on the theory of cold disorders in both books reveal that, during the 2 centuries period from mid Tang to early Song Dynasties, the texts as a carrier for the transmission of such theory in both show no distinct changes, but only with minor revisions and improvements.

  7. Nanoscale spinel LiFeTiO4 for intercalation pseudocapacitive Li(+) storage.

    PubMed

    Chen, Ruiyong; Knapp, Michael; Yavuz, Murat; Ren, Shuhua; Witte, Ralf; Heinzmann, Ralf; Hahn, Horst; Ehrenberg, Helmut; Indris, Sylvio

    2015-01-14

    Intercalation pseudocapacitive Li(+) storage has been recognized recently in metal oxide materials, wherein Li(+) intercalation into the lattice is not solid-state diffusion-limited. This may bridge the performance gap between electrochemical capacitors and battery materials. To date, only a few materials with desired crystal structure and with well-defined nanoarchitectures have been found to exhibit such attractive behaviour. Herein, we report for the first time that nanoscale spinel LiFeTiO4 as a cathode material for Li-ion batteries exhibits intercalation pseudocapacitive Li(+) storage behaviour. Nanoscale LiFeTiO4 nanoparticles with native carbon coating were synthesized by a sol-gel route. A fast and large-amount of Li(+) storage (up to 1.6 Li(+) per formula unit over cycling) in the nanoscale LiFeTiO4 host has been achieved without compromising kinetics.

  8. Changes in DNA methylation and transgenerational mobilization of a transposable element (mPing) by the Topoisomerase II inhibitor, Etoposide, in rice

    PubMed Central

    2012-01-01

    Background Etoposide (epipodophyllotoxin) is a chemical commonly used as an anti-cancer drug which inhibits DNA synthesis by blocking topoisomerase II activity. Previous studies in animal cells have demonstrated that etoposide constitutes a genotoxic stress which may induce genomic instability including mobilization of normally quiescent transposable elements (TEs). However, it remained unknown whether similar genetically mutagenic effects could be imposed by etoposide in plant cells. Also, no information is available with regard to whether the drug may cause a perturbation of epigenetic stability in any organism. Results To investigate whether etoposide could generate genetic and/or epigenetic instability in plant cells, we applied etoposide to germinating seeds of six cultivated rice (Oryza sativa L.) genotypes including both subspecies, japonica and indica. Based on the methylation-sensitive gel-blotting results, epigenetic changes in DNA methylation of three TEs (Tos17, Osr23 and Osr36) and two protein-encoding genes (Homeobox and CDPK-related genes) were detected in the etoposide-treated plants (S0 generation) in four of the six studied japonica cultivars, Nipponbare, RZ1, RZ2, and RZ35, but not in the rest japonica cultivar (Matsumae) and the indica cultivar (93-11). DNA methylation changes in the etoposide-treated S0 rice plants were validated by bisulfite sequencing at both of two analyzed loci (Tos17 and Osr36). Transpositional activity was tested for eight TEs endogenous to the rice genome in both the S0 plants and their selfed progenies (S1 and S2) of one of the cultivars, RZ1, which manifested heritable phenotypic variations. Results indicated that no transposition occurred in the etoposide-treated S0 plants for any of the TEs. Nonetheless, a MITE transposon, mPing, showed rampant mobilization in the S1 and S2 progenies descended from the drug-treated S0 plants. Conclusions Our results demonstrate that etoposide imposes a similar genotoxic stress on

  9. Anti-inflammatory effect of Yu-Ping-Feng-San via TGF-β1 signaling suppression in rat model of COPD

    PubMed Central

    Yang, Zhong-Shan; Yan, Jin-Yuan; Han, Ni-Ping; Zhou, Wei; Cheng, Yu; Zhang, Xiao-Mei; Li, Ning; Yuan, Jia-Li

    2016-01-01

    Objective(s): Yu-Ping-Feng-San (YPFS) is a classical traditional Chinese medicine that is widely used for treatment of the diseases in respiratory systems, including chronic obstructive pulmonary disease (COPD) recognized as chronic inflammatory disease. However, the molecular mechanism remains unclear. Here we detected the factors involved in transforming growth factor beta 1 (TGF-β1)/Smad2 signaling pathway and inflammatory cytokines, to clarify whether YPFS could attenuate inflammatory response dependent on TGF-β1/Smad2 signaling in COPD rats or cigarette smoke extract (CSE)-treated human bronchial epithelial (Beas-2B) cells. Materials and Methods: The COPD rat model was established by exposure to cigarette smoke and intratracheal instillation of lipopolysaccharide, YPFS was administered to the animals. The efficacy of YPFS was evaluated by comparing the severity of pulmonary pathological damage, pro-inflammation cytokines, collagen related genes and the activation of TGF-β1/Smad2 signaling pathway. Furthermore, CSE-treated cells were employed to confirm whether the effect of YPFS was dependent on the TGF-β1/Smad2 signaling via knockdown Smad2 (Si-RNA), or pretreatment with the inhibitor of TGF-β1. Results: Administration of YPFS effectively alleviated injury of lung, suppressed releasing of pro-inflammatory cytokines and collagen deposition in COPD animals (P<0.05), whereas exogenous TGF-β1 promoted releasing of IL-1β, IL-6, TNFα (P<0.05). Administration YPFS reduced inflammatory response significantly, also down-regulated TGF-β1/Smad2 signaling in vivo and in vitro. Unexpectedly, knockdown Smad2 or inhibition of TGF-β1 abolished anti-inflammatory effect of YPFS in CSE-treated cells. Conclusion: YPFS accomplished anti-inflammatory effects mainly by suppressing phosphorylation of Smad2, TGF-β1/Smad2 signaling pathway was required for YPFS-mediated anti-inflammation in COPD rats or CSE-treated Beas-2B cells. PMID:27803787

  10. Decameric uracil complexes around Li+.

    PubMed

    Zins, Emilie-Laure; Pepe, Claude; Schröder, Detlef

    2010-07-01

    Electrospray ionization (ESI) in combination with mass spectrometry (MS) experiments were carried out to study decameric uracil complexes cationized with Li(+) ion. A previous study has shown that, under specific experimental conditions, a particularly intense peak of the decamer U(10)Li(+) is formed, which was referred to as an indication for so-called 'magic number' cluster. In order to gain more insight on the structure of this decameric complex, here, we report experimental studies concerning the kinetics of the fragmentation. In accordance with the new experimental data, structural models were constructed and fully optimized using ab initio and density functional theory quantum chemistry calculations. The theoretical study allowed us to propose a stable gas-phase structure which is compatible with all experimental findings. 2010 John Wiley & Sons, Ltd.

  11. LiDAR: Providing structure

    USGS Publications Warehouse

    Vierling, Lee A.; Martinuzzi, Sebastián; Asner, Gregory P.; Stoker, Jason M.; Johnson, Brian R.

    2011-01-01

    Since the days of MacArthur, three-dimensional (3-D) structural information on the environment has fundamentally transformed scientific understanding of ecological phenomena (MacArthur and MacArthur 1961). Early data on ecosystem structure were painstakingly laborious to collect. However, as reviewed and reported in recent volumes of Frontiers(eg Vierling et al. 2008; Asner et al.2011), advances in light detection and ranging (LiDAR) remote-sensing technology provide quantitative and repeatable measurements of 3-D ecosystem structure that enable novel ecological insights at scales ranging from the plot, to the landscape, to the globe. Indeed, annual publication of studies using LiDAR to interpret ecological phenomena increased 17-fold during the past decade, with over 180 new studies appearing in 2010 (ISI Web of Science search conducted on 23 Mar 2011: [{lidar AND ecol*} OR {lidar AND fores*} OR {lidar AND plant*}]).

  12. Determining the 7Li(n,γ) cross section via Coulomb dissociation of 8Li

    NASA Astrophysics Data System (ADS)

    Izsák, R.; Horváth, Á.; Kiss, Á.; Seres, Z.; Galonsky, A.; Bertulani, C. A.; Fülöp, Zs.; Baumann, T.; Bazin, D.; Ieki, K.; Bordeanu, C.; Carlin, N.; Csanád, M.; Deák, F.; DeYoung, P.; Frank, N.; Fukuchi, T.; Gade, A.; Galaviz, D.; Hoffman, C. R.; Peters, W. A.; Schelin, H.; Thoennessen, M.; Veres, G. I.

    2013-12-01

    The applicability of Coulomb dissociation reactions to determine the cross section for the inverse neutron capture reaction was explored using the reaction 8Li(γ,n)7Li. A 69.5 MeV/nucleon 8Li beam was incident on a Pb target, and the outgoing neutron and 7Li nucleus were measured in coincidence. The deduced (n,γ) excitation function is consistent with data for the direct capture reaction 7Li(n,γ)8Li and with low-energy effective field theory calculations.

  13. Measurement of Li+ Ion Transport Numbers in PEO-LiX Complexes.

    DTIC Science & Technology

    1988-03-01

    elsewheres. The salts under study were LiCF3SO3, LiAlC 4, LiAsF., LiBF4 and LiPF, and the PEO-LiX concentrations were 50:1, 25:1, 8:1, 4:1, 2:1 and 1...1 PEO- LIBF4 19 .37 8:1 PEO- LIBF4 28 .40 f-. ___ ___ ___ ____ ___ __ _ ___ ____ ___ ___ ___ ____ ___ _NP 0 U 2 U,o P;. a C S S C.) * - , ~.CD 0 0 XI

  14. Diffusion and possible freezing phases of Li-ions in LiFePO4

    NASA Astrophysics Data System (ADS)

    Yiu, Yuen; Toft-Petersen, Rasmus; Ehlers, Georg; Vaknin, David

    Elastic and inelastic neutron scattering studies of LiFePO4 single crystal reveal new Li-ion diffusion properties relevant to its function as Li-battery materials. In the past decade there has been broad interest in LiFePO4 and its related compounds, largely due to the applications of these materials as cathodes in Li- batteries. This is owing to these materials' high charge-discharge ability and conductivity, both of which are by virtue of the Li-ions' high mobility. In this talk, we present our findings on the temperature and directional dependence of Li-ions' diffusion in LiFePO4. LiFePO4 adopts the olivine structure at room temperature (Space group: Pnma), which contains channels along principal crystalline directions that allow Li-ion motion. Elastic neutron scattering reveals lowering of symmetry from the Pnma structure below room temperature, which can be interpreted as the freezing of Li-ions, and can be subsequently linked to the reported decrease in Li-ion conductivity. Inelastic neutron scattering, in the 35K to 720K temperature range, shows temperature dependence, as well as anisotropy (i.e. along 0K0 versus 00L) of Li-ion diffusion. Ames Laboratory is supported by U.S. DOE, BES, DMSE, under Contract #DE-AC02-07CH11358. Spallation Neutron Source of Oak Ridge National Laboratory is sponsored by U.S. DOE, BES, SUFD.

  15. Ultralong Lifespan and Ultrafast Li Storage: Single-Crystal LiFePO4 Nanomeshes.

    PubMed

    Zhang, Yan; Zhang, Hui Juan; Feng, Yang Yang; Fang, Ling; Wang, Yu

    2016-01-27

    A novel LiFePO4 material, in the shape of a nanomesh, has been rationally designed and synthesized based on the low crystal-mismatch strategy. The LiFePO4 nanomesh possesses several advantages in morphology and crystal structure, including a mesoporous structure, its crystal orientation that is along the [010] direction, and a shortened Li-ion diffusion path. These properties are favorable for their application as cathode in Li-ion batteries, as these will accelerate the Li-ion diffusion rate, improve the Li-ion exchange between the LiFePO4 nanomesh and the electrolyte, and reduce the Li-ion capacitive behavior during Li intercalation. So the LiFePO4 nanomesh exhibits a high specific capacity, enhanced rate capability, and strengthened cyclability. The method developed here can also be extended to other similar systems, for instance, LiMnPO4 , LiCoPO4 , and LiNiPO4 , and may find more applications in the designed synthesis of functional materials.

  16. Thermal stability of LiPF 6 salt and Li-ion battery electrolytes containing LiPF 6

    NASA Astrophysics Data System (ADS)

    Yang, Hui; Zhuang, Guorong V.; Ross, Philip N.

    The thermal stability of the neat lithium hexafluorophosphate (LiPF 6) salt and of 1 molal (m) solutions of LiPF 6 in prototypical Li-ion battery solvents was studied with thermogravimetric analysis (TGA) and on-line Fourier transform infrared (FTIR). Pure LiPF 6 salt is thermally stable up to 107 °C in a dry inert atmosphere, and its decomposition path is a simple dissociation producing lithium fluoride (LiF) as solid and PF 5 as gaseous products. In the presence of water (300 ppm) in the carrier gas, its decomposition onset temperature is lowered as a result of direct thermal reaction between LiPF 6 and water vapor to form phosphorous oxyfluoride (POF 3) and hydrofluoric acid (HF). No new products were observed in 1 m solutions of LiPF 6 in ethylene carbonate (EC), dimethyl carbonate (DMC) and ethyl methyl carbonate (EMC) by on-line TGA-FTIR analysis. The storage of the same solutions in sealed containers at 85 °C for 300-420 h did not produce any significant quantity of new products as well. In particular, no alkylflurophosphates were found in the solutions after storage at elevated temperature. In the absence of either an impurity like alcohol or cathode active material that may (or may not) act as a catalyst, there is no evidence of thermally induced reaction between LiPF 6 and the prototypical Li-ion battery solvents EC, PC, DMC or EMC.

  17. A homologues prediction strategy for comprehensive screening and characterization of C21 steroids from Xiao-ai-ping injection by using ultra high performance liquid chromatography coupled with high resolution hybrid quadrupole-orbitrap mass spectrometry.

    PubMed

    Wang, Pei-le; Sun, Zhi; Lv, Xiao-Jing; Xu, Tan-Ye; Jia, Qing-Quan; Liu, Xin; Zhang, Xiao-Fang; Zhu, Zhen-Feng; Zhang, Xiao-Jian

    2017-09-22

    Because of the complicated chemical composition of Traditional Chinese Medicines, their chemical profile study has been a great challenge. In the present work, a homologues prediction strategy for rapid screening and identification of C21 steroids in Xiao-ai-ping injection was developed by using an ultra high performance liquid chromatography coupled with high resolution hybrid quadrupole-orbitrap mass spectrometry. This strategy was characterized by the design of C21 steroidal skeleton, substituent group and glycan chain in an orderly way, which could quickly and efficiently screen the interested precursor ions. As a result, a total of 95C21 steroids including 47 potential new ones were identified or tentatively identified, which greatly expanded our knowledge of C21 steroids in Xiao-ai-ping injection. The results indicated that the homologues prediction strategy not only provided an efficient technique to screen and identify target constituents, but also offered a new perspective for discovery new components in Traditional Chinese Medicines. Copyright © 2017. Published by Elsevier B.V.

  18. Li+ ion dynamics in strontium bismuthate glasses

    NASA Astrophysics Data System (ADS)

    Dutta, A.; Ghosh, A.

    2004-11-01

    Ion transport in Li2O-Bi2O3-SrO glasses has been studied in the frequency range 10 Hz-2 MHz and in the temperature range 263-483 K. The variation of the dc conductivity and the activation energy of these glasses with composition has been compared with those of bismuthate and lead bismuthate glasses. The frequency dependent conductivity has been studied using both modulus and conductivity formalisms. We have observed that the variation of the power law exponent with Li2O content is in contrast to that for the Li2O-Bi2O3 and Li2O-Bi2O3-PbO glasses. The values of the non-exponential parameter for the Li2O-Bi2O3-SrO glasses are lower than those for the binary Li2O-Bi2O3 glasses.

  19. Measurement of Solubility of Metallic Lithium Dissolved in Molten LiCl-Li2O

    NASA Astrophysics Data System (ADS)

    Burak, Adam J.; Simpson, Michael F.

    2016-10-01

    The solubility of lithium metal in molten LiCl-Li2O mixtures has been measured at various concentrations of Li2O ranging from 0 wt.% to 2.7 wt.% at a temperature of approximately 670-680°C. After contacting molten lithium with molten LiCl-Li2O for several hours to achieve equilibrium saturation, samples were taken by freezing the salt onto a room-temperature steel rod and dissolving in water for analysis. Both volume of hydrogen gas generated and volume of titrated HCl were measured to investigate two different approaches to calculating the lithium concentration. There appeared to be no effect of Li2O concentration on the Li solubility in the salt. But the results vary between different methods of deducing the amount of dissolved Li. The H2 collection method is recommended, but care must be taken to ensure all of the H2 has been included.

  20. Li@organic superhalogens: possible electrolytes in Li-ion batteries.

    PubMed

    Naaresh Reddy, G; Parida, Rakesh; Giri, Santanab

    2017-08-31

    Inorganic superhalogens are commonly used as anionic counterparts in Li-ion batteries. In an endeavour to prepare better electrolytes, we have modelled the anionic part with different organic heterocyclic-based superhalogens. First principles calculations on those organic superhalogens reveal that the Li-binding energy is at par with that of the Li-salt of a common electrolyte. Out of five different halogen free organic heterocycles, Li[C3BN2(NO2)4] and Li[C2BNO(NO2)3] are found to be mostly suitable as electrolytes in Li-ion batteries. Molecular dynamics simulation studies on C2BNO(NO2)3(-), C3BN2(NO2)4(-), Li[C2BNO(NO2)3] and Li[C3BN2(NO2)4] also reveal that the structures are dynamically stable.

  1. On the Photoelectron Spectra of Li4

    NASA Technical Reports Server (NTRS)

    Bauschlicher, Charles W., Jr.; Arnold, James O. (Technical Monitor)

    1996-01-01

    The most stable structure for Li4(-) is found to be the rhombus. Electron detachment from this structure does not seem able to fully explain the photoelectron spectra. The computed results are consistent with those Rao, Jena, and Ray who have proposed that the experimental spectra consists of a superposition of detachment from the Li4(-) rhombus and tetrahedron, forming the singlet and triplet states of Li4, respectively.

  2. Interaction of 11Li with 208Pb

    NASA Astrophysics Data System (ADS)

    Vinodkumar, A. M.; Loveland, W.; Yanez, R.; Leonard, M.; Yao, L.; Bricault, P.; Dombsky, M.; Kunz, P.; Lassen, J.; Morton, A. C.; Ottewell, D.; Preddy, D.; Trinczek, M.

    2013-04-01

    Background: 11Li is one of the most studied halo nuclei. The fusion of 11Li with 208Pb is the subject of a number of theoretical studies with widely differing predictions, ranging over four orders of magnitude, for the fusion excitation function.Purpose: The purpose was to measure the excitation function for the 11Li + 208Pb reaction.Methods: A stacked foil and degrader assembly of 208Pb targets was irradiated with a 11Li beam producing center-of-target beam energies from above-barrier to near-barrier energies (40-29 MeV). The intensity of the 11Li beam (chopped) was 1250 particles/s and the beam on-target time was 34 h. The α decay of the stopped evaporation residues (EVRs) was detected in an α-detector array at each beam energy in the beam-off period (the beam was on for ≤5 ns and then off for 170 ns).Results: The observed nuclidic yields of 212/215At and 214At are consistent with being produced in the complete fusion of 11Li with 208Pb. The observed yields of 213At appear to be the result of the breakup of 11Li into 9Li+2n, with the 9Li fusing with 208Pb. The magnitudes of the total fusion cross sections are substantially less than most theoretical predictions.Conclusions: It is possible to measure the EVR production cross sections resulting from the interaction of 11Li with 208Pb using current-generation radioactive beam facilities. Both complete fusion and breakup fusion processes occur in the interaction of 11Li with 208Pb. An important breakup process leads to the fusion of the 9Li fragment with 208Pb.

  3. Li-rich anti-perovskite Li3OCl films with enhanced ionic conductivity

    SciTech Connect

    Lu, XJ; Wu, G; Howard, JW; Chen, AP; Zhao, YS; Daemen, LL; Jia, QX

    2014-08-13

    Anti-perovskite solid electrolyte films were prepared by pulsed laser deposition, and their room-temperature ionic conductivity can be improved by more than an order of magnitude in comparison with its bulk counterpart. The cyclability of Li3OCl films in contact with lithium was evaluated using a Li/Li3OCl/Li symmetric cell, showing self-stabilization during cycling test.

  4. Photoemission study of Li@C60

    NASA Astrophysics Data System (ADS)

    Yagi, Hajime; Ogasawara, Naoko; Zenki, Masashi; Miyazaki, Takafumi; Hino, Shojun

    2016-05-01

    Ultraviolet and X-ray photoelectron spectra (UPS and XPS) of thin films prepared by either depositing or applying [Li@C60]+(PF6)- on the substrates are presented. The UPS and XPS of [Li@C60]+(PF6)- applied films suggest that PF6- anions come out from the surface by annealing at 250 °C. The UPS and XPS of the deposited thin films indicate that the film does not contain PF6- anion but is composed of only Li@C60. Changing the sublimation temperature reveals that encapsulated Li cations begin to escape from the C60 cage when heated above 550 °C.

  5. Nanoscale LiFePO4 and Li4Ti5O12 for High Rate Li-ion Batteries

    SciTech Connect

    Jaiswal, A.; Horne, C.R.; Chang, O.; Zhang, W.; Kong, W.; Wang, E.; Chern, T.; Doeff, M. M.

    2009-08-04

    The electrochemical performances of nanoscale LiFePO4 and Li4Ti5O12 materials are described in this communication. The nanomaterials were synthesized by pyrolysis of an aerosol precursor. Both compositions required moderate heat-treatment to become electrochemically active. LiFePO4 nanoparticles were coated with a uniform, 2-4 nm thick carbon-coating using an organic precursor in the heat treatment step and showed high tap density of 1.24 g/cm3, in spite of 50-100 nm particle size and 2.9 wtpercent carbon content. Li4Ti5O12 nanoparticles were between 50-200 nm in size and showed tap density of 0.8 g/cm3. The nanomaterials were tested both in half cell configurations against Li-metal and also in LiFePO4/Li4Ti5O12 full cells. Nano-LiFePO4 showed high discharge rate capability with values of 150 and 138 mAh/g at C/25 and 5C, respectively, after constant C/25 charges. Nano-Li4Ti5O12 also showed high charge capability with values of 148 and 138 mAh/g at C/25 and 5C, respectively, after constant C/25 discharges; the discharge (lithiation) capability was comparatively slower. LiFePO4/Li4Ti5O12 full cells deliver charge/discharge capacity values of 150 and 122 mAh/g at C/5 and 5C, respectively.

  6. Lithiation of Li2SnO3 and Li2SnS3 in context of Li-ion battery materials

    NASA Astrophysics Data System (ADS)

    Howard, Jason; Holzwarth, N. A. W.

    The closed pack layered crystal material (space group 15 (C 2 / c)) Li2 SnO3 has been studied as a possible anode material since the late 1990's. The material undergoes an irreversible decomposition to Li2 O and LiX Sn alloys during the first lithiation cycle. The crystal material Li2 SnS3 of the same structure was recently proposed as an electrolyte material. The question is posed whether Li2 SnS3 would be a good electrolyte or whether it could function as an anode material similar to Li2 SnO3 . In this research a model is proposed for the lithiation process of Li2 SnO3 and Li2 SnS3 ; Li - Li2 SnS3 interfaces are also examined. The results show Li2 SnO3 begins to decompose at approximately Li2 + 0 . 5 SnO3 . In Li2 SnS3 the lithiation process shows it can lithiate to Li2 + 1 SnS3 without significant lattice distortion, volume expansion, or decomposition. Li - Li2 SnS3 interfaces are shown to be unstable, showing the formation of Li2 S . Supported by NSF Grant DMR-1105485 and DMR-1507942.

  7. Modification of LiCl-LiBr-KBr electrolyte for LiAl/FeS{sub 2} batteries

    SciTech Connect

    Kaun, T.D.; Jansen, A.N.; Henriksen, G.L.; Vissers, D.R.

    1996-06-01

    The bipolar LiAl/FeS{sub 2} battery is being developed to achieve the high performance and long cycle life needed for electric vehicle application. The molten-salt (400 to 440 C operation) electrolyte composition for this battery has evolved to support these objectives. An earlier change to LiCl-LiBr-KBr electrolyte is responsible for significantly increased cycle life (up to 1,000 cycles). Recent electrolyte modification has significantly improved cell performance; approximately 50% increased power, with increased high rate capacity utilization. Results are based on power-demanding EV driving profile test at 600 W/kg. The effects of adding small amounts (1--5 mol%) of LiF and LiI to LiCl-LiBr-KBr electrolyte are discussed. By cyclic voltammetry, the modified electrolytes exhibit improved FeS{sub 2} electrochemistry. Electrolyte conductivity is little changed, but high current density (200 mA/cm{sup 2}) performance improved by approximately 50%. A specific feature of the LiI addition is an enhanced cell overcharge tolerance rate from 2.5 to 5 mA/cm{sup 2}. The rate of overcharge tolerance is related to electrolyte properties and negative electrode lithium activity. As a result, the charge balancing of a bipolar battery configuration with molten-salt electrolyte is improved to accept greater cell-to-cell deviations.

  8. Response to Comment on "Cycling Li-O₂ batteries via LiOH formation and decomposition".

    PubMed

    Liu, Tao; Kim, Gunwoo; Carretero-González, Javier; Castillo-Martínez, Elizabeth; Grey, Clare P

    2016-05-06

    We described a lithium-oxygen (Li-O2) battery comprising a graphene electrode, a dimethoxyethane-based electrolyte, and H2O and lithium iodide (LiI) additives, lithium hydroxide (LiOH) being the predominant discharge product. We demonstrate, in contrast to the work of Shen et al., that the chemical reactivity between LiOH and the triiodide ion (I3 (-)) to form IO3 (-) indicates that LiOH can be removed on charging; the electrodes do not clog, even after multiple cycles, confirming that solid products are reversibly removed.

  9. Li ion diffusion in LiAlO2 investigated by Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Hu, Qiwei; Lei, Li; Jiang, Xiaodong; Feng, Zhe Chuan; Tang, Mingjun; He, Duanwei

    2014-11-01

    The temperature dependence of Li ions behavior of γ-LiAlO2 has been studied from 78 to 873 K. On heating, the Li ions underwent positional disordering along the structural channels, with the Li ions related modes at 220, 366 and 400 cm-1 broadening and weakening dramatically. An anomalous maximum in the bandwidths of the Li ions related modes is observed. It should be apparent that there are at least two distinct thermally activated processes. A model suggested by Andrade and Porto is used to describe the linewidth of a phonon.

  10. The Impact of Li Grain Size on Coulombic Efficiency in Li Batteries

    PubMed Central

    Mehdi, B. Layla; Stevens, Andrew; Qian, Jiangfeng; Park, Chiwoo; Xu, Wu; Henderson, Wesley A.; Zhang, Ji-Guang; Mueller, Karl T.; Browning, Nigel D.

    2016-01-01

    One of the most promising means to increase the energy density of state-of-the-art lithium Li-ion batteries is to replace the graphite anode with a Li metal anode. While the direct use of Li metal may be highly advantageous, at present its practical application is limited by issues related to dendrite growth and low Coulombic efficiency, CE. Here operando electrochemical scanning transmission electron microscopy (STEM) is used to directly image the deposition/stripping of Li at the anode-electrolyte interface in a Li-based battery. A non-aqueous electrolyte containing small amounts of H2O as an additive results in remarkably different deposition/stripping properties as compared to the “dry” electrolyte when operated under identical electrochemical conditions. The electrolyte with the additive deposits more Li during the first cycle, with the grain sizes of the Li deposits being significantly larger and more variable. The stripping of the Li upon discharge is also more complete, i.e., there is a higher cycling CE. This suggests that larger grain sizes are indicative of better performance by leading to more uniform Li deposition and an overall decrease in the formation of Li dendrites and side reactions with electrolyte components, thus potentially paving the way for the direct use of Li metal in battery technologies. PMID:27703188

  11. The Impact of Li Grain Size on Coulombic Efficiency in Li Batteries

    NASA Astrophysics Data System (ADS)

    Mehdi, B. Layla; Stevens, Andrew; Qian, Jiangfeng; Park, Chiwoo; Xu, Wu; Henderson, Wesley A.; Zhang, Ji-Guang; Mueller, Karl T.; Browning, Nigel D.

    2016-10-01

    One of the most promising means to increase the energy density of state-of-the-art lithium Li-ion batteries is to replace the graphite anode with a Li metal anode. While the direct use of Li metal may be highly advantageous, at present its practical application is limited by issues related to dendrite growth and low Coulombic efficiency, CE. Here operando electrochemical scanning transmission electron microscopy (STEM) is used to directly image the deposition/stripping of Li at the anode-electrolyte interface in a Li-based battery. A non-aqueous electrolyte containing small amounts of H2O as an additive results in remarkably different deposition/stripping properties as compared to the “dry” electrolyte when operated under identical electrochemical conditions. The electrolyte with the additive deposits more Li during the first cycle, with the grain sizes of the Li deposits being significantly larger and more variable. The stripping of the Li upon discharge is also more complete, i.e., there is a higher cycling CE. This suggests that larger grain sizes are indicative of better performance by leading to more uniform Li deposition and an overall decrease in the formation of Li dendrites and side reactions with electrolyte components, thus potentially paving the way for the direct use of Li metal in battery technologies.

  12. The Impact of Li Grain Size on Coulombic Efficiency in Li Batteries

    SciTech Connect

    Mehdi, B. Layla; Stevens, Andrew; Qian, Jiangfeng; Park, Chiwoo; Xu, Wu; Henderson, Wesley A.; Zhang, Ji-Guang; Mueller, Karl T.; Browning, Nigel D.

    2016-10-05

    One of the most promising means to increase the energy density of state-of-the-art lithium (Li)-ion batteries is to replace the graphite anode with a Li metal anode1, 2, 3. While the direct use of Li metal may be highly advantageous4,5, at present its practical application is limited by issues related to dendrite growth and low Coulombic efficiency (CE)6. Here operando electrochemical scanning transmission electron microscopy (STEM) is used to directly image the deposition/stripping of Li at the anode-electrolyte interface in a Li-based battery. A non-aqueous electrolyte containing small amounts of H2O as an additive results in remarkably different deposition/stripping properties as compared to the "dry" electrolyte when operated under identical electrochemical conditions. The electrolyte with the additive deposits more Li during the first cycle, with the grain sizes of the Li deposits being significantly larger and more variable. The stripping of the Li upon discharge is also more complete, i.e., there is a higher cycling CE. This suggests that larger grain sizes are indicative of better performance by leading to more uniform Li deposition and an overall decrease in the formation of Li dendrites and side reactions with electrolyte components, thus potentially paving the way for the direct use of Li metal in battery technologies.

  13. Electrochemistry of LiCl-Li2O-H2O Molten Salt Systems

    SciTech Connect

    Natalie J. Gese; Batric Pesic

    2013-03-01

    Uranium can be recovered from uranium oxide (UO2) spent fuel through the combination of the oxide reduction and electrorefining processes. During oxide reduction, the spent fuel is introduced to molten LiCl-Li2O salt at 650 degrees C and the UO2 is reduced to uranium metal via two routes: (1) electrochemically, and (2) chemically by lithium metal (Li0) that is produced electrochemically. However, the hygroscopic nature of both LiCl and Li2O leads to the formation of LiOH, contributing hydroxyl anions (OH-), the reduction of which interferes with the Li0 generation required for the chemical reduction of UO2. In order for the oxide reduction process to be an effective method for the treatment of uranium oxide fuel, the role of moisture in the LiCl-Li2O system must be understood. The behavior of moisture in the LiCl-Li2O molten salt system was studied using cyclic voltammetry, chronopotentiometry and chronoamperometry, while reduction to hydrogen was confirmed with gas chromatography.

  14. The Impact of Li Grain Size on Coulombic Efficiency in Li Batteries.

    PubMed

    Mehdi, B Layla; Stevens, Andrew; Qian, Jiangfeng; Park, Chiwoo; Xu, Wu; Henderson, Wesley A; Zhang, Ji-Guang; Mueller, Karl T; Browning, Nigel D

    2016-10-05

    One of the most promising means to increase the energy density of state-of-the-art lithium Li-ion batteries is to replace the graphite anode with a Li metal anode. While the direct use of Li metal may be highly advantageous, at present its practical application is limited by issues related to dendrite growth and low Coulombic efficiency, CE. Here operando electrochemical scanning transmission electron microscopy (STEM) is used to directly image the deposition/stripping of Li at the anode-electrolyte interface in a Li-based battery. A non-aqueous electrolyte containing small amounts of H2O as an additive results in remarkably different deposition/stripping properties as compared to the "dry" electrolyte when operated under identical electrochemical conditions. The electrolyte with the additive deposits more Li during the first cycle, with the grain sizes of the Li deposits being significantly larger and more variable. The stripping of the Li upon discharge is also more complete, i.e., there is a higher cycling CE. This suggests that larger grain sizes are indicative of better performance by leading to more uniform Li deposition and an overall decrease in the formation of Li dendrites and side reactions with electrolyte components, thus potentially paving the way for the direct use of Li metal in battery technologies.

  15. Response to Comment on "Cycling Li-O₂ batteries via LiOH formation and decomposition".

    PubMed

    Liu, Tao; Kim, Gunwoo; Carretero-González, Javier; Castillo-Martínez, Elizabeth; Bayley, Paul M; Liu, Zigeng; Grey, Clare P

    2016-05-06

    Lithium-oxygen (Li-O2) batteries cycle reversibly with lithium iodide (LiI) additives in dimethoxyethane (DME) to form lithium hydroxide (LiOH). Viswanathan et al. argue that because the standard redox potential of the four-electron (e(-)) reaction, 4OH(-) ↔ 2H2O + O2 + 4e(-), is at 3.34 V versus Li(+)/Li, LiOH cannot be removed by the triiodide ion (I3(-)). However, under nonaqueous conditions, this reaction will occur at a different potential. LiOH also reacts chemically with I3(-) to form IO3(-), further studies being required to determine the relative rates of the two reactions on electrochemical charge.

  16. Direct observation of Li diffusion in Li-doped ZnO nanowires

    NASA Astrophysics Data System (ADS)

    Li, Guohua; Yu, Lei; Hudak, Bethany M.; Chang, Yao-Jen; Baek, Hyeonjun; Sundararajan, Abhishek; Strachan, Douglas R.; Yi, Gyu-Chul; Guiton, Beth S.

    2016-05-01

    The direct observation of Li diffusion in Li-doped zinc oxide nanowires (NWs) was realized by using in situ heating in the scanning transmission electron microscope (STEM). A continuous increase of low atomic mass regions within a single NW was observed between 200 °C and 600 °C when heated in vacuum, which was explained by the conversion of interstitial to substitutional Li in the ZnO NW host lattice. A kick-out mechanism is introduced to explain the migration and conversion of the interstitial Li (Lii) to Zn-site substitutional Li (LiZn), and this mechanism is verified with low-temperature (11 K) photoluminescence measurements on as-grown and annealed Li-doped zinc oxide NWs, as well as the observation of an increase of NW surface roughing with applied bias.

  17. Matrix isolation spectroscopy of metal atoms generated by laser ablation. I - The Li/Ar, Li/Kr, and Li/Xe systems

    NASA Astrophysics Data System (ADS)

    Fajardo, Mario E.; Carrick, P. G.; Kenney, John W., III

    1991-05-01

    Results of experiments on Li-doped rare-gas solids (Ar, Kr, and Xe) prepared by laser ablation of solid Li are presented, including NUV-visible absorption spectra and photobleaching and annealing studies of the matrices, as well as visible emission spectra of the laser-ablated Li plume. The UV-visible absorption spectra of Li/Ar and Li/Kr matrices generated by condensing the range gas and laser-ablated Li atoms at 12 K are dominated by a 'blue-shifted triplet' absorption not observed in previously published studies. Control experiments on Li/Ar and Li/Kr matrices generated using a Knudsen oven as the Li atom source showed exclusively an 'unshifted triplet' absorption, in agreement with previous studies. The new absorption features are attributed to Li atoms trapped in novel sites in the Ar and Kr solids.

  18. Mixed salts of LiTFSI and LiBOB for stable LiFePO4-based batteries at elevated temperatures

    SciTech Connect

    Chen, Xilin; Xu, Wu; Engelhard, Mark H.; Zheng, Jianming; Zhang, Yaohui; Ding, Fei; Qian, Jiangfeng; Zhang, Ji-Guang

    2014-01-01

    To achieve stable long-term cycling stability at elevated temperatures, mixed salts of LiTFSI and LiBOB are used to replace LiPF6 salt in non-aqueous electrolytes for LiFePO4-based batteries. It is found that adding LiBOB in LiTFSI-based electrolytes effectively prevents the severe corrosion to Al current collectors that often is observed in LiTFSI-based electrolytes, which have high thermal stability. The cells using LiTFSI-LiBOB-based electrolytes demonstrate superior high temperature (60 °C) stability and very similar room temperature performance (i.e., cycling stability and rate capability) when compared to cells using the LiPF6-based electrolyte.

  19. Investigation of the role of 10Li resonances in the halo structure of 11Li through the 11Li (p , d)10Li transfer reaction

    NASA Astrophysics Data System (ADS)

    Sanetullaev, A.; Kanungo, R.; Tanaka, J.; Alcorta, M.; Andreoiu, C.; Bender, P.; Chen, A. A.; Christian, G.; Davids, B.; Fallis, J.; Fortin, J. P.; Galinski, N.; Gallant, A. T.; Garrett, P. E.; Hackman, G.; Hadinia, B.; Ishimoto, S.; Keefe, M.; Krücken, R.; Lighthall, J.; McNeice, E.; Miller, D.; Purcell, J.; Randhawa, J. S.; Roger, T.; Rojas, A.; Savajols, H.; Shotter, A.; Tanihata, I.; Thompson, I. J.; Unsworth, C.; Voss, P.; Wang, Z.

    2016-04-01

    The first measurement of the one-neutron transfer reaction 11Li(p,d)10Li performed using the IRIS facility at TRIUMF with a 5.7 A MeV11Li beam interacting with a solid H2 target is reported. The 10Li residue was populated strongly as a resonance peak with energy Er = 0.62 ± 0.04 MeV having a total width Γ = 0.33 ± 0.07 MeV. The angular distribution of this resonance is characterized by neutron occupying the 1p1/2 orbital. A DWBA analysis yields a spectroscopic factor of 0.67 ± 0.12 for p1/2 removal strength from the ground state of 11Li to the region of the peak.

  20. Investigation of the role of 10Li resonances in the halo structure of 11Li through the 11Li(p,d)10Li transfer reaction

    DOE PAGES

    Sanetullaev, A.; Kanungo, R.; Tanaka, J.; ...

    2016-03-02

    Here, the first measurement of the one-neutron transfer reaction 11Li(p,d)10Li performed using the IRIS facility at TRIUMF with a 5.7A MeV11Li beam interacting with a solid H2 target is reported. The 10Li residue was populated strongly as a resonance peak with energy Er = 0.62 ± 0.04 MeV having a total width Γ = 0.33 ± 0.07 MeV. The angular distribution of this resonance is characterized by neutron occupying the 1p1/2 orbital. A DWBA analysis yields a spectroscopic factor of 0.67 ± 0.12 for p1/2 removal strength from the ground state of 11Li to the region of the peak.

  1. Utility of Li and Li Isotopes as Tracers of Continental Weathering

    NASA Astrophysics Data System (ADS)

    James, R. H.; Wimpenny, J. B.; Pogge von Strandmann, P.; Kisakurek, B.; Hathorne, E. C.; Anand, P.; Burton, K. W.

    2008-12-01

    Lithium is potentially an attractive tracer of continental weathering because its two isotopes have a large relative mass difference, it is unaffected by biological activity and it is only slightly incompatible during magmatic processes so tends to be relatively uniformly distributed in the Earth's crust. Moreover, Li is conservative in the oceans, with a residence time of ca. 1 million years, and it is isotopically uniform on a global scale (δ7Li ~+31‰). Seminal work by Lui Chan and her co-workers has shown that the Li and Li isotope balance of the oceans is maintained by inputs of high-temperature hydrothermal fluids at oceanic ridges (with δ7Li ~+6.7‰) and dissolved Li from rivers (average δ7Li = +23‰), and low-temperature removal of Li into oceanic basalts and marine sediments. Despite this potential, relatively little is known about the behaviour of Li during continental weathering. In this study, we will present an overview of the work that we have conducted on Li and Li isotopes in rivers, soils and estuaries from catchments in Greenland, Iceland and the Himalaya, as well as laboratory studies of mineral dissolution and precipitation. Each of these case studies illustrates the effects of weathering processes on the riverine isotope signal, and the estuarine data illustrate how this signal is transferred to the oceans. Our data suggest that variations in rock type have little effect on riverine δ7Li; the principal control is preferential removal of 6Li into secondary minerals formed during weathering, leaving the residual waters enriched in 7Li. In subglacial environments, where weathering rates are very low, uptake of Li by ferric oxyhydroxides formed during sulphide oxidation is important. Our results clearly demonstrate that weathering processes can exert a significant effect on the Li isotope composition of natural waters. In order to understand whether changes in such processes with time are preserved, we have also generated records of the past

  2. Chen Li: China's elder psychologist.

    PubMed

    Blowers, G H

    1998-01-01

    Chen Li is one of a small group of psychologists in China who trained abroad early in their careers, returned to teach and do research, and continued doing so into later life beyond normal retirement age. His contacts with a number of prominent psychologists in England and Germany in the 1930s, and his inadvertent position at the center of a political row in China in the 1960s, leading to the shutting down of psychology for 10 years, made him historically important. Known for his work in organizational psychology and education, he is a distinguished psychologist and educational leader. Although trained as an experimentalist, he now embraces a broader view of psychology but remains emphatic it should be applied to real-life problems.

  3. Attainable gravimetric and volumetric energy density of Li-S and li ion battery cells with solid separator-protected Li metal anodes.

    PubMed

    McCloskey, Bryan D

    2015-11-19

    As a result of sulfur's high electrochemical capacity (1675 mA h/gs), lithium-sulfur batteries have received significant attention as a potential high-specific-energy alternative to current state-of-the-art rechargeable Li ion batteries. For Li-S batteries to compete with commercially available Li ion batteries, high-capacity anodes, such as those that use Li metal, will need to be enabled to fully exploit sulfur's high capacity. The development of Li metal anodes has focused on eliminating Coulombically inefficient and dendritic Li cycling, and to this end, an interesting direction of research is to protect Li metal by employing mechanically stiff solid-state Li(+) conductors, such as garnet phase Li7La3Zr2O12 (LLZO), NASICON-type Li1+xAlxTi2-x(PO4)3 (LATP), and Li2S-P2S5 glasses (LPS), as electrode separators. Basic calculations are used to quantify useful targets for solid Li metal protective separator thickness and cost to enable Li metal batteries in general and Li-S batteries specifically. Furthermore, maximum electrolyte-to-sulfur ratios that allow Li-S batteries to compete with Li ion batteries are calculated. The results presented here suggest that controlling the complex polysulfide speciation chemistry in Li-S cells with realistic, minimal electrolyte loading presents a meaningful opportunity to develop Li-S batteries that are competitive on a specific energy basis with current state-of-the-art Li ion batteries.

  4. A martyr for modernity: Qiu Jin -- feminist warrior, and revolutionary.

    PubMed

    Fan, H; Mangan, J A

    2001-01-01

    Qui Jin, at one level, was an oriental twentieth-century Judith, the mythical Jewish widow from Bethulia who cut off the head of Holofernes, the Assyrian general besieging the city, thus saving the Israelites from destruction. Qui Jin was, as Judith was, a self-reliant heroine who when others seemed 'helpless and demoralized undertook to save them single-handedly', or in her case virtually single-handedly. This, of course, was both her making and her unmaking. In Chinese terms the story of Qui Jin, like the story of Judith if less famous, less publicised, more recent, is the story of an icon at once central and at the same time marginal to tradition. She contradicted the most cherished customs on Confucian Chinese culture. She was a radical force who thrust her way to the centre of the concentric circles of customs surrounding this culture and was pushed back to the margins by conservatism. Nevertheless Qui Jin was not without success. She challenged a long-established mythology of exclusively masterful patriarchy - and created a counter myth of purposeful patriotic feminism. She was a counter-cultural icon who changed perceptions of Chinese femininity. She gave courage, confidence and purpose to those women who came after her and absorbed her ambitions for modern Chinese womanhood. For them she was a modern national heroine and a personification of a modern nation of equal men and women. For Qui Jin the body was an instrument of female revolution to be trained, strengthened and prepared for confrontation. As a revolutionary militant she was a failure; as a revolutionary talisman she was a success. For the Chinese women of the 1911 Revolution hers was an exemplary emancipatory story: subscribe, struggle, sacrifice. Patriotism through feminism is the purpose. Her heroism was firmly outside the historic patriarchal order. Her adulation is thus all the more remarkable because of the profound traditions she rejected, the controversial mannerisms she adopted, the uncompromising attitudes she embraced. She eschewed motherhood, abandoned marriage, dismissed femininity, and yet won acclaim in the most traditional of cultures. Qui Jin was hardly a cynosure of universal acclaim but she was admired, respected and emulated by radical Chinese women and men seeking a new society accommodating women. Her modern feminism struggled to overcome an ancient patriarchy. Here was her appeal. She exuded no moral ambiguity. Consequently, if she was demonized by the conventional; she was deified by the radical - and inspired them as the contemplated and attempted to construct the future. There is a point, of course, that should not be overlooked. Qui Jin, in fact, is not divorced from occidental culture and political iconography. Qui Jin is closely associated with the attitudes, aspirations and fantasies of modern Western feminism. As Margarita Stocker observes, a 'romantic heroine, angry feminist, radical, activist is one example of a pervasive figure', in modern Western cultural mythology 'a figure we may sum up as the Woman with a Gun'. Force, that potent means to power, is available to the gun user irrespective of age of sex, with a resulting 'crucial alteration in the sexual politics of violence'. The Woman with a Gun can now be emphatically heroic - without duplicity, without deceitfulness, without subterfuge. Moral ambiguity in action has been abandoned. She becomes an unambiguous potent force - an armed woman faces an armed man on equal terms - physically, psychologically, morally. Equality offers the legal right and responsibility to kill in the name of patriotism. Modern culture has just caught up with Qui Jin.

  5. Nanomaterials Meet Li-ion Batteries.

    PubMed

    Kwon, Nam Hee; Brog, Jean-Pierre; Maharajan, Sivarajakumar; Crochet, Aurélien; Fromm, Katharina M

    2015-01-01

    Li-ion batteries are used in many applications in everyday life: cell phones, laser pointers, laptops, cordless drillers or saws, bikes and even cars. Yet, there is room for improvement in order to make the batteries smaller and last longer. The Fromm group contributes to this research focusing mainly on nanoscale lithium ion cathode materials. This contribution gives an overview over our current activities in the field of batteries. After an introduction on the nano-materials of LiCoO(2) and LiMnPO(4), the studies of our cathode composition and preparation will be presented.

  6. Effect of a pyrrolidinium zwitterion on charge/discharge cycle properties of Li/LiCoO2 and graphite/Li cells containing an ionic liquid electrolyte

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Seitaro; Yoshizawa-Fujita, Masahiro; Takeoka, Yuko; Rikukawa, Masahiro

    2016-11-01

    Ionic liquids (ILs) containing zwitterions have been studied as electrolytes for lithium-ion batteries (LIBs). The effects of addition of a pyrrolidinium zwitterion in an IL electrolyte on the thermal and electrochemical stability and charge/discharge properties of Li/LiCoO2 and graphite/Li cells were investigated. The thermal decomposition temperature of the IL electrolyte composed of N-methyl-N-propylpyrrolidinium bis(fluorosulfonyl)amide ([P13][FSA])/lithium bis(trifluoromethylsulfonyl)amide (LiTFSA) with 3-(1-butylpyrrolidinium)propane-1-sulfonate (Bpyps) as the zwitterionic additive, the thermal decomposition temperature was about 300 °C. The electrochemical window of [P13][FSA]/LiTFSA/Bpyps was 0-+5.4 V vs. Li/Li+, which was almost identical to that of [P13][FSA]/LiTFSA. Li|electrolyte|LiCoO2 cells containing the IL/Bpyps electrolyte system exhibited high capacities in the cut-off voltage range of 3.0-4.6 V, even after 50 cycles. The increase in the interfacial resistance between the electrolyte and cathode with cycling was suppressed. In the cyclic voltammograms of cells employing a graphite electrode, the intercalation/deintercalation of lithium ions were observed in the range of 0 and + 0.4 V vs. Li/Li+. Further, graphite|electrolyte|Li cells containing [P13][FSA]/LiTFSA/Bpyps exhibited stable charge/discharge cycle behaviour over 50 cycles.

  7. First-principles study of Li ion diffusion in LiFePO4

    NASA Astrophysics Data System (ADS)

    Ouyang, Chuying; Shi, Siqi; Wang, Zhaoxiang; Huang, Xuejie; Chen, Liquan

    2004-03-01

    The diffusion mechanism of Li ions in the olivine LiFePO4 is investigated from first-principles calculations. The energy barriers for possible spatial hopping pathways are calculated with the adiabatic trajectory method. The calculations show that the energy barriers running along the c axis are about 0.6, 1.2, and 1.5 eV for LiFePO4, FePO4, and Li0.5FePO4, respectively. However, the other migration pathways have much higher energy barriers resulting in very low probability of Li-ion migration. This means that the diffusion in LiFePO4 is one dimensional. The one-dimensional diffusion behavior has also been shown with full ab initio molecular dynamics simulation, through which the diffusion behavior is directly observed.

  8. Li ion diffusion mechanisms in LiFePO4: an ab initio molecular dynamics study.

    PubMed

    Yang, Jianjun; Tse, John S

    2011-11-17

    The mechanisms for thermal (self) diffusion of Li ions in fully lithiated LiFePO(4) have been investigated with spin polarized ab initio molecular dynamics calculations. The effect of electron correlation is taken into account with the GGA+U formalism. It was found that Li ion diffusion is not a continuous process but through a series of jumps from one site to another. A dominant process is the hopping between neighboring Li sites around the PO(4) groups, which results in a zigzag pathway along the crystallographic b-axis. This observation is in agreement with a recent neutron diffraction experiment. A second process involves the collaborative movements of the Fe ions leading to the formation of antisite defects and promotes Li diffusion across the Li ion channels. The finding of the second mechanism demonstrates the benefit of ab initio molecular dynamics simulation in sampling diffusion pathways that may not be anticipated.

  9. First-principle studies on the Li-Te system

    NASA Astrophysics Data System (ADS)

    Wang, Youchun; Tian, Fubo; Li, Da; Duan, Defang; Liu, Yunxian; Liu, Bingbing; Zhou, Qiang; Cui, Tian

    2017-01-01

    First-principle evolutionary calculation was performed to search for all probable stable lithium tellurium compounds. In addition to the well-known structures of Fm-3m Li2Te and Pnma Li2Te, several novel structures, including those of P4/nmm Li2Te, Imma Li8Te2, and C2/m Li9Te2, were determined under high pressure. The transformation sequence of Li2Te induced by pressure was presented as follows. The phase transition occurred at 7.5 GPa while transforming from Fm-3m phase to Pnma structure, then transformed to P4/nmm phase at 14 GPa. P4/nmm Li2Te can remain stable at least up to 140 GPa. Li8Te2 and Li9Te2 were stable at 8-120 GPa and 80-120 GPa, respectively. Interestingly, Li8Te2 and Li9Te2 were predicted to be metallic under high pressure, Li2Te would metalize on compression. P4/nmm Li2Te is likely a super ionic conductor due to the special characteristic. Metallic P4/nmm Li2Te may be a candidate mixed conductor material under extreme pressure. Charge transfer was studied using Bader charge analysis. Charge transferred from Li to Te, and the relative debilitated ionicity between Li and Te atoms existed at high pressure.

  10. Layered Li-Mn-M-oxides as cathodes for Li-ion batteries:. Recent trends

    NASA Astrophysics Data System (ADS)

    Shaju, K. M.; Subba Rao, G. V.; Chowdari, B. V. R.

    2002-12-01

    There is an increasing demand for manganese (Mn) based mixed oxides which can effectively replace the presently used LiCoO2 as cathode in Li-ion batteries (LIB). The well-studied spinel, LiMn2O4 and its doped derivatives give a capacity of 100-120 mAh/g, but show capacity-fading on cycling especially above 55°C. The layered LiMnO2, isostructural to LiCoO2 (so called O3-structure) can be a viable cathode. However, studies have shown that it undergoes conversion to spinel structure on cycling and thus gives capacity-fading. Other alternative systems recently studied are: O2-structured layered Li-M-Mn-oxides with the general formula Li(2/3)+x(MyMn1-y)O2, M = Li, Ni, Co; x ≤ 0.33 and y = 0.1-0.67, O3-Li(Ni1/2Mn1/2)O2, Li(NixCo1-2xMnx)O2, and M'-substituted Li2MnO3 (M' = Ni, Co, Cr). Some of them are shown to have stable cycling performance, good rate-capability and structural stability over charge-discharge cycling in the 2.5-4.6 V region. Further, the electrochemical processes in the above mixed oxides have been shown to involve Ni2+/4+ or Cr3+/6+ redox couple, thus invoking novel ideas to develop new cathode materials. A brief review of the work done on the above O2- and O3-layered Li-Mn-M-oxides (M = metal) as cathodes for LIB is presented.

  11. Line shift, line asymmetry, and the ^6Li/^7Li isotopic ratio determination

    NASA Astrophysics Data System (ADS)

    Cayrel, R.; Steffen, M.; Chand, H.; Bonifacio, P.; Spite, M.; Spite, F.; Petitjean, P.; Ludwig, H.-G.; Caffau, E.

    2007-10-01

    Context: Line asymmetries are generated by convective Doppler shifts in stellar atmospheres, especially in metal-poor stars, where convective motions penetrate to higher atmospheric levels. Such asymmetries are usually neglected in abundance analyses. The determination of the ^6Li/^7Li isotopic ratio is prone to suffering from such asymmetries, as the contribution of ^6Li is a slight blending reinforcement of the red wing of each component of the corresponding ^7Li line, with respect to its blue wing. Aims: The present paper studies the halo star HD 74000 and estimates the impact of convection-related asymmetries on the Li isotopic ratio determination. Methods: Two methods are used to meet this aim. The first, which is purely empirical, consists in deriving a template profile from another element that can be assumed to originate in the same stellar atmospheric layers as Li I, producing absorption lines of approximately the same equivalent width as individual components of the ^7Li I resonance line. The second method consists in conducting the abundance analysis based on NLTE line formation in a 3D hydrodynamical model atmosphere, taking into account the effects of photospheric convection. Results: The results of the first method show that the convective asymmetry generates an excess absorption in the red wing of the ^7Li absorption feature that mimics the presence of ^6Li at a level comparable to the hitherto published values. This opens the possibility that only an upper limit on ^6Li/^7Li has thus far been derived. The second method confirms these findings. Conclusions: From this work, it appears that a systematic reappraisal of former determinations of ^6Li abundances in halo stars is warranted. Based on observations carried out at the European Southern Observatory (ESO), under prog. ID 75.D-0600. Tables 1-3, and additional references are only available in electronic form at http://www.aanda.org

  12. Antiperovskite Li 3 OCl superionic conductor films for solid-state Li-ion batteries

    DOE PAGES

    Lü, Xujie; Howard, John W.; Chen, Aiping; ...

    2016-02-02

    We prepared antiperovskite Li3OCl superionic conductor films via pulsed laser deposition using a composite target. A significantly enhanced ionic conductivity of 2.0 × 10-4 S cm-1 at room temperature is achieved, and this value is more than two orders of magnitude higher than that of its bulk counterpart. Moreover, the applicability of Li3OCl as a solid electrolyte for Li-ion batteries is demonstrated.

  13. LiSICON-Ionic Liquid Electrolyte for Lithium Ion Battery

    DTIC Science & Technology

    2011-08-15

    LiSICON cell with 0.75M LiTFSI /PYR13+FSI- had a capacity of 325 mAh g-1 and coulombic efficiency of 99.8% during cycling at 80 ?C. 15. SUBJECT TERMS 16...with different Li salt concentrations at elevated temperature. A carbon anode in a LiSICON cell with 0.75M LiTFSI /PYR13 + FSI - had a capacity of...triflouromethanesulfonyl)imide ( LiTFSI , 99%, Acros) were used inside an inert atmosphere glovebox. LiTFSI was dissolved in the PYR13 + FSI - and

  14. Ultracold collisions between Li atoms and Li{sub 2} diatoms in high vibrational states

    SciTech Connect

    Quemener, Goulven; Launay, Jean-Michel; Honvault, Pascal

    2007-05-15

    We have performed a quantum-dynamical study of vibrational deexcitation and elastic scattering at ultralow collision energies for the bosonic system {sup 7}Li+{sup 7}Li{sub 2} and for the fermionic system {sup 6}Li+{sup 6}Li{sub 2} with diatomic molecules in high vibrational states. Inelastic rates show a strong and irregular dependence on the vibrational state of the diatomic molecule. For the highest vibrational state which lies near the dissociation limit, vibrational deexcitation processes are not suppressed, but rather depleted, for both bosonic and fermionic systems.

  15. [100]-Oriented LiFePO4 Nanoflakes toward High Rate Li-Ion Battery Cathode.

    PubMed

    Li, Zhaojin; Peng, Zhenzhen; Zhang, Hui; Hu, Tao; Hu, Minmin; Zhu, Kongjun; Wang, Xiaohui

    2016-01-13

    [100] is believed to be a tough diffusion direction for Li(+) in LiFePO4, leading to the belief that the rate performance of [100]-oriented LiFePO4 is poor. Here we report the fabrication of 12 nm-thick [100]-oriented LiFePO4 nanoflakes by a simple one-pot solvothermal method. The nanoflakes exhibit unexpectedly excellent electrochemical performance, in stark contrast to what was previously believed. Such an exceptional result is attributed to a decreased thermodynamic transformation barrier height (Δμb) associated with increased active population.

  16. Strain imaging of a LiCoO2 cathode in a Li-ion battery

    NASA Astrophysics Data System (ADS)

    Matsushita, Yuki; Osaka, Ryuma; Butsugan, Kenta; Takata, Keiji

    2016-09-01

    Li-ion batteries have been recognized as promising devices for a sustainable society. Layered LiCoO2 and graphite are commonly used as electrode materials for Li-ion batteries. When charging and discharging, Li-ions are extracted or inserted into the interlayers, which causes changes in volume. Scanning probe microscopy (SPM) can allow high resolution imaging of these volume changes, which enables us to investigate Li-ion migration without destruction. We observed volume changes in the LiCoO2 cathode using SPM and successfully imaged the distribution of the volume changes corresponding to the LiCoO2 particles. Volume changes in the interspace were significantly larger than those in the particles. The large volume changes are caused by electrolyte flux induced by changes in concentration of Li ions. The volume changes were greatly reduced when the electrolyte dried out. The dry-out and infiltration of electrolyte between the LiCoO2 particles and the current collector spread out with the procedure of degradation of the batteries. The boundaries between the dry-out and infiltration regions acted as barriers of electrolyte flux.

  17. Uniform second Li ion intercalation in solid state ɛ-LiVOPO4

    NASA Astrophysics Data System (ADS)

    Wangoh, Linda W.; Sallis, Shawn; Wiaderek, Kamila M.; Lin, Yuh-Chieh; Wen, Bohua; Quackenbush, Nicholas F.; Chernova, Natasha A.; Guo, Jinghua; Ma, Lu; Wu, Tianpin; Lee, Tien-Lin; Schlueter, Christoph; Ong, Shyue Ping; Chapman, Karena W.; Whittingham, M. Stanley; Piper, Louis F. J.

    2016-08-01

    Full, reversible intercalation of two Li+ has not yet been achieved in promising VOPO4 electrodes. A pronounced Li+ gradient has been reported in the low voltage window (i.e., second lithium reaction) that is thought to originate from disrupted kinetics in the high voltage regime (i.e., first lithium reaction). Here, we employ a combination of hard and soft x-ray photoelectron and absorption spectroscopy techniques to depth profile solid state synthesized LiVOPO4 cycled within the low voltage window only. Analysis of the vanadium environment revealed no evidence of a Li+ gradient, which combined with almost full theoretical capacity confirms that disrupted kinetics in the high voltage window are responsible for hindering full two lithium insertion. Furthermore, we argue that the uniform Li+ intercalation is a prerequisite for the formation of intermediate phases Li1.50VOPO4 and Li1.75VOPO4. The evolution from LiVOPO4 to Li2VOPO4 via the intermediate phases is confirmed by direct comparison between O K-edge absorption spectroscopy and density functional theory.

  18. Uniform second Li ion intercalation in solid state ϵ-LiVOPO{sub 4}

    SciTech Connect

    Wangoh, Linda W.; Quackenbush, Nicholas F.; Sallis, Shawn; Wiaderek, Kamila M.; Ma, Lu; Wu, Tianpin; Chapman, Karena W.; Lin, Yuh-Chieh; Ong, Shyue Ping; Wen, Bohua; Chernova, Natasha A.; Whittingham, M. Stanley; Guo, Jinghua; Lee, Tien-Lin; Schlueter, Christoph; Piper, Louis F. J.

    2016-08-01

    Full, reversible intercalation of two Li{sup +} has not yet been achieved in promising VOPO{sub 4} electrodes. A pronounced Li{sup +} gradient has been reported in the low voltage window (i.e., second lithium reaction) that is thought to originate from disrupted kinetics in the high voltage regime (i.e., first lithium reaction). Here, we employ a combination of hard and soft x–ray photoelectron and absorption spectroscopy techniques to depth profile solid state synthesized LiVOPO{sub 4} cycled within the low voltage window only. Analysis of the vanadium environment revealed no evidence of a Li{sup +} gradient, which combined with almost full theoretical capacity confirms that disrupted kinetics in the high voltage window are responsible for hindering full two lithium insertion. Furthermore, we argue that the uniform Li{sup +} intercalation is a prerequisite for the formation of intermediate phases Li{sub 1.50}VOPO{sub 4} and Li{sub 1.75}VOPO{sub 4}. The evolution from LiVOPO{sub 4} to Li{sub 2}VOPO{sub 4} via the intermediate phases is confirmed by direct comparison between O K–edge absorption spectroscopy and density functional theory.

  19. Molecular evolution of the Li/li chemical defence polymorphism in white clover (Trifolium repens L.).

    PubMed

    Olsen, K M; Sutherland, B L; Small, L L

    2007-10-01

    White clover (Trifolium repens) is naturally polymorphic for cyanogenesis (hydrogen cyanide release following tissue damage). The ecological factors favouring cyanogenic and acyanogenic plants have been examined in numerous studies over the last half century, making this one of the best-documented examples of an adaptive polymorphism in plants. White clover cyanogenesis is controlled by two, independently segregating Mendelian genes: Ac/ac controls the presence/absence of cyanogenic glucosides; and Li/li controls the presence/absence of their hydrolysing enzyme, linamarase. In this study, we examine the molecular evolution and population genetics of Li as it relates to the cyanogenesis polymorphism. We report here that Li exists as a single-copy gene in plants possessing linamarase activity, and that the absence of enzyme activity in li/li plants is correlated with the absence of much or all of the gene from the white clover genome. Consistent with this finding, we confirm by reverse transcription-polymerase chain reaction that Li gene expression is absent in plants lacking enzyme activity. In a molecular population genetic analysis of Li and three unlinked genes using a worldwide sample of clover plants, we find an absence of nucleotide variation and statistically significant deviations from neutrality at Li; these findings are consistent with recent positive directional selection at this cyanogenesis locus.

  20. Uniform second Li ion intercalation in solid state {var_epsilon}-LiVOPO4

    SciTech Connect

    Wangoh, Linda W.; Sallis, Shawn; Wiaderek, Kamila M.; Lin, Yuh-Chieh; Wen, Bohua; Quackenbush, Nicholas F.; Chernova, Natasha A.; Guo, Jinghua; Ma, Lu; Wu, Tianpin; Lee, Tien-Lin; Schlueter, Christoph; Ong, Shyue Ping; Chapman, Karena W.; Whittingham, M. Stanley; Piper, Louis F. J.

    2016-08-01

    Full, reversible intercalation of two Li+ has not yet been achieved in promising VOPO4 electrodes. A pronounced Li+ gradient has been reported in the low voltage window (i.e. second lithium reaction) that is thought to originate from disrupted kinetics in the high voltage regime (i.e first lithium reaction). Here we employ a combination of hard and soft x–ray photoelectron and absorption spectroscopy techniques to depth profile solid state synthesized LiVOPO4 cycled within the low voltage window only. Analysis of the vanadium environment revealed no evidence of a Li+ gradient, which combined with almost full theoretical capacity confirms that disrupted kinetics in the high voltage window are responsible for hindering full two lithium insertion. Furthermore, we argue that the uniform Li+ intercalation is a prerequisite for the formation of intermediate phases Li1:50VOPO4 and Li1:75VOPO4. The evolution from LiVOPO4 to Li2VOPO4 via the intermediate phases is confirmed by direct comparison between O K–edge absorption spectroscopy and density functional theory.

  1. Ferromagnetism in chemically reduced LiNbO3 and LiTaO3 crystals

    NASA Astrophysics Data System (ADS)

    Yan, Tao; Ye, Ning; Xu, Liuwei; Sang, Yuanhua; Chen, Yanxue; Song, Wei; Long, Xifa; Wang, Jiyang; Liu, Hong

    2016-05-01

    The ferromagnetism of bulk LiNbO3 and LiTaO3 at room temperature was investigated for the first time in the present work. The stoichiometric LiNbO3 is non-magnetic, while congruent LiNbO3 and LiTaO3 show very weak ferromagnetism. After chemical reduction in a mixture of zinc and lithium carbonate powders under flowing nitrogen, the ferromagnetic behavior of each sample became clear, with an increased value of magnetization. The saturation magnetization, the magnetic remanence and the coercive field of reduced congruent LiNbO3 are 7.0  ×  10-3 emu g-1, 0.65  ×  10-3 emu g-1 and 0.050 kOe, respectively. The ferromagnetism of chemically reduced LiNbO3 and LiTaO3 can be explained by considering the intrinsic Li vacancies, the appearance of Nb4+ (or Ta4+) on the surface with non-zero net spin and the oxygen vacancies at the surface.

  2. Specification For ST-5 Li Ion Battery

    NASA Technical Reports Server (NTRS)

    Castell, Karen D.; Day, John H. (Technical Monitor)

    2000-01-01

    This Specification defines the general requirements for rechargeable Space Flight batteries intended for use in the ST-5 program. The battery chemistry chosen for this mission is lithium ion (Li-Ion).

  3. Li + grafting of ion irradiated polyethylene

    NASA Astrophysics Data System (ADS)

    Švorčík, V.; Rybka, V.; Vacík, J.; Hnatowicz, V.; Öchsner, R.; Ryssel, H.

    1999-02-01

    Foils of oriented polyethylene (PE) were irradiated with 63 keV Ar + and 155 keV Xe + ions to different fluences at room temperature and then doped from water solution of LiCl. The as irradiated and irradiated plus doped samples were examined by IR, EPR and neutron depth profiling (NDP) technique. The sheet resistance was also measured by the standard two points method. After Li salt doping of ion modified layer of PE, a reaction between degraded macromolecules and Li occur and thus a new chemical structure C-Li + is formed. Owing to the presence of these cations on the polymer chain, the irradiated plus doped layer exhibits higher electric conductivity compared to as-irradiated ones.

  4. LiDAR as an Exploration Tool

    DOE Data Explorer

    Boschmann, D.; Diles, J.; Clarno, J.; Meigs, A.; Walsh, P.

    2011-01-01

    Using LiDAR to identify structural and volcanic evolution of a Miocene-Pleistocene age bimodal volcanic complex and implications for geothermal potential. The file includes an updated geologic map, methods, and preliminary results.

  5. Nanotechnology in Li-ion Batteries

    SciTech Connect

    Mukaibo, Hitomi

    2010-06-04

    This is the second of three talks on nanostructures for li-ion batteries. The talks provide an up-to-date review of the issues and challenges facing Li-ion battery research with special focus on how nanostructures/ nanotechnology are being applied to this field. Novel materials reported as prospective candidates for anode, cathode and electrolyte will be summarized. The expected role of nanostructures in improving the performance of Li-ion batteries and the actual pros and cons of using such structures in this device will be addressed. Electrochemical experiments used to study Li-ion batteries will also be discussed. This includes the introduction to the standard experimental set-up and how experimental data (from charge-discharge experiments, cyclic voltammetry, impedance spectroscopy, etc) are interpreted.

  6. Li'l Red Schoolhouse workshops

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Education specialists at Stennis conduct staff development workshops for elementary and secondary teachers of math, science and technology and other subjects as well as specialized workshops conducted in the NASA Li'l Red Schoolhouse.

  7. Laboratory submillimeter transition frequencies of Li-7H and Li-6H. [used for abundance investigations in red giant stars

    NASA Technical Reports Server (NTRS)

    Plummer, G. M.; Herbst, E.; De Lucia, F. C.

    1984-01-01

    The fundamental (J = 1 - 0) rotational transition frequencies of Li-7H and Li-6H in their ground (v = 0) vibrational states and of Li-7H in its first excited (v = 1) vibrational state have been measured in the laboratory. Use of these transition frequencies should permit astronomical investigations of LiH abundances in red giant stars of high lithium abundance.

  8. Unravelling Li-Ion Transport from Picoseconds to Seconds: Bulk versus Interfaces in an Argyrodite Li6PS5Cl-Li2S All-Solid-State Li-Ion Battery.

    PubMed

    Yu, Chuang; Ganapathy, Swapna; de Klerk, Niek J J; Roslon, Irek; van Eck, Ernst R H; Kentgens, Arno P M; Wagemaker, Marnix

    2016-09-07

    One of the main challenges of all-solid-state Li-ion batteries is the restricted power density due to the poor Li-ion transport between the electrodes via the electrolyte. However, to establish what diffusional process is the bottleneck for Li-ion transport requires the ability to distinguish the various processes. The present work investigates the Li-ion diffusion in argyrodite Li6PS5Cl, a promising electrolyte based on its high Li-ion conductivity, using a combination of (7)Li NMR experiments and DFT based molecular dynamics simulations. This allows us to distinguish the local Li-ion mobility from the long-range Li-ion motional process, quantifying both and giving a coherent and consistent picture of the bulk diffusion in Li6PS5Cl. NMR exchange experiments are used to unambiguously characterize Li-ion transport over the solid electrolyte-electrode interface for the electrolyte-electrode combination Li6PS5Cl-Li2S, giving unprecedented and direct quantitative insight into the impact of the interface on Li-ion charge transport in all-solid-state batteries. The limited Li-ion transport over the Li6PS5Cl-Li2S interface, orders of magnitude smaller compared with that in the bulk Li6PS5Cl, appears to be the bottleneck for the performance of the Li6PS5Cl-Li2S battery, quantifying one of the major challenges toward improved performance of all-solid-state batteries.

  9. Lost in Translation (LiT)

    PubMed Central

    Dollery, Colin T

    2014-01-01

    Translational medicine is a roller coaster with occasional brilliant successes and a large majority of failures. Lost in Translation 1 (‘LiT1’), beginning in the 1950s, was a golden era built upon earlier advances in experimental physiology, biochemistry and pharmacology, with a dash of serendipity, that led to the discovery of many new drugs for serious illnesses. LiT2 saw the large-scale industrialization of drug discovery using high-throughput screens and assays based on affinity for the target molecule. The links between drug development and university sciences and medicine weakened, but there were still some brilliant successes. In LiT3, the coverage of translational medicine expanded from molecular biology to drug budgets, with much greater emphasis on safety and official regulation. Compared with R&D expenditure, the number of breakthrough discoveries in LiT3 was disappointing, but monoclonal antibodies for immunity and inflammation brought in a new golden era and kinase inhibitors such as imatinib were breakthroughs in cancer. The pharmaceutical industry is trying to revive the LiT1 approach by using phenotypic assays and closer links with academia. LiT4 faces a data explosion generated by the genome project, GWAS, ENCODE and the ‘omics’ that is in danger of leaving LiT4 in a computerized cloud. Industrial laboratories are filled with masses of automated machinery while the scientists sit in a separate room viewing the results on their computers. Big Data will need Big Thinking in LiT4 but with so many unmet medical needs and so many new opportunities being revealed there are high hopes that the roller coaster will ride high again. PMID:24428732

  10. LiNbO3 Cylinder Fiber

    NASA Technical Reports Server (NTRS)

    Kornreich, Philip

    2004-01-01

    We have successfully fabricate optical fiber with a thin layer of LiNbO3 at the boundary of the glass core and clear glass cladding. The construction of this fiber is based on our successful Semiconductor Cylinder Fibers (SCF). A schematic representation of a LiN bo, Cylinder Fiber. These fibers can be used as light modulators, sonar detectors and in other applications. The core diameter of the fiber is sufficiently small compared to the light wavelength and the indices of refraction of the core and cladding glasses are sufficiently close in value so that there is sufficient light at the core cladding boundary to interact with the LiNbO3 layer. This fiber functions best when just a single light mode propagates through the fiber. The idea for a LiNbO3 Cylinder Fiber came from Dr. Tracee Jamison of NASA. The optical properties of LiNbO3 can be changed with strain or the application of an electric field. Thus these fibers can be used as acoustic sensors as for example in a sonar. They can also be used as electric field operated light modulators. However, for this application the fibers would be made with a cross section in the form of a "D". The core with its surrounding LiNbO, layer would be close to the flat portion of the "D" shaped fiber. Two metal contacts would be deposited on the flat portion of the fiber on either side of the core. A voltage applied across these contacts will result in an electric field in the core region that can be used for modulating the optical properties of the LiNbO3 layer. To our knowledge this is the first ever LiNbO3 Cylinder Fiber made.

  11. LiNbO3 Cylinder Fiber

    NASA Technical Reports Server (NTRS)

    2004-01-01

    We have successfully fabricate optical fiber with a thin layer of LiNbO3 at the boundary of the glass core and dear glass cladding. The construction of this fiber is based on our successful Semiconductor Cylinder Fibers (SCF). A schematic representation of a LiNbO3 Cylinder Fiber is shown. These fibers can be used as light modulators, sonar detectors and in other applications. The core diameter of the fiber is sufficiently small compared to the light wavelength and the indices of refraction of the core and cladding glasses are sufficiently close in value so that there is sufficient light at the core cladding boundary to interact with the LiNbO3 layer. This fiber functions best when just a single light mode propagates through the fiber. The idea for a LiNbO3 Cylinder Fiber came from Dr. Tracee Jamison of NASA. The optical properties of LiNbO3 can be changed with strain or the application of an electric field. Thus these fibers can be used as acoustic sensors as for example in a sonar. They can also be used as electric field operated light modulators. However, for this application the fibers would be made with a cross section in the form of a 'D'. The core with its surrounding LiNbO, layer would be close to the flat portion of the 'D' shaped fiber. Two metal contacts would be deposited on the flat portion of the fiber on either side of the core. A voltage applied across these contacts will result in an electric field in the core region that can be used for modulating the optical properties of the LiNbO, layer. To our knowledge this is the first ever LiNbO, Cylinder Fiber made.

  12. Negative Electrodes for Li-Ion Batteries

    SciTech Connect

    Kinoshita, Kim; Zaghib, Karim

    2001-10-01

    Graphitized carbons have played a key role in the successful commercialization of Li-ion batteries. The physicochemical properties of carbon cover a wide range; therefore identifying the optimum active electrode material can be time consuming. The significant physical properties of negative electrodes for Li-ion batteries are summarized, and the relationship of these properties to their electrochemical performance in nonaqueous electrolytes, are discussed in this paper.

  13. Studies on the thermoluminescence spectra and thermal stability of LiF:Mg,Cu, LiF:Mg,Cu,Na and LiF:Mg,Cu,Si

    NASA Astrophysics Data System (ADS)

    Yang, B.; Lu, Q.; Wang, S.; Townsend, P. D.

    2005-09-01

    Four thermoluminescence (TL) peaks at 60-90, 100-130, 130-180 and 180-220 °C (the main peak) were observed from LiF:Mg,Cu, LiF:Mg,Cu,Na and LiF:Mg,Cu,Si. The recorded emission bands were at 375 and 414 nm in LiF:Mg,Cu, at 379 and 424 nm in LiF:Mg,Cu,Na and 378 and 425 nm in LiF:Mg,Cu,Si. The loss of TL intensity and temperature shift of the main peak were observed in LiF:Mg,Cu, LiF:Mg,Cu,Na, LiF:Mg,Cu,Si, LiF:Mg,Cu,Na,Si and LiF:Mg as well as in LiF:Mg,Cu,P, when the sample was heated to above 270 °C. It is suggested that those are the common behaviors in the Mg doped LiF samples, if the concentration of magnesium is properly high. Those behaviors are supposed to be associated with the precipitated phase of Mg and the secondary phase - Mg/(other impurities) complex.

  14. Lithium diffusion in spinel Li4Ti5O12 and LiTi2O4 films detected with 8Liβ -NMR

    NASA Astrophysics Data System (ADS)

    Sugiyama, Jun; Umegaki, Izumi; Uyama, Takeshi; McFadden, Ryan M. L.; Shiraki, Susumu; Hitosugi, Taro; Salman, Zaher; Saadaoui, Hassan; Morris, Gerald D.; MacFarlane, W. Andrew; Kiefl, Robert F.

    2017-09-01

    Diffusion of Li+ in (111) oriented thin films of the spinels Li4Ti5O12 and LiTi2O4 has been studied with 8Liβ -detected NMR in the temperature range between 5 and 310 K. In Li4Ti5O12 , the spin-lattice relaxation rate (1 /T1 ) versus temperature shows a clear maximum around 100 K (=Tmax ) which we attribute to magnetic freezing of dilute Ti3 + local magnetic moments, consistent with the results of magnetization and muon spin relaxation (μ+SR ) measurements. The decrease in 1 /T1 with temperature above Tmax indicates that Li+ starts to diffuse with a thermal activation energy (Ea) of 0.11(1) eV. In LiTi2O4 , on the contrary, as temperature increases from 200 K, 1 /T1 increases monotonically up to 310 K. This suggests that Li also starts to diffuse above 200 K with Ea=0.16 (2 ) eV in LiTi2O4 . Comparison with conventional Li-NMR on Li4Ti5O12 implies that both β -NMR and μ+SR sense short-range Li motion, i.e., a jump diffusion of Li+ to the nearest neighboring sites.

  15. One-pot liquid phase synthesis of (100-x)Li3PS4-xLiI solid electrolytes

    NASA Astrophysics Data System (ADS)

    Phuc, Nguyen Huu Huy; Hirahara, Eito; Morikawa, Kei; Muto, Hiroyuki; Matsuda, Atsunori

    2017-10-01

    (100-x)Li3PS4-xLiI solid electrolytes are successfully prepared using a simple process proposed in this study. The results show that the heat-treatment process plays a crucial role in the formation of the final product. In the case of x = 33.3%, 2Li3PS4-1LiI, a nearly pure crystalline phase of Li7P2S8I (LPSI), is obtained. The cyclic voltammogram result and DC polarization curves indicate that the interfacial layer between LPSI and the Li metal is stable. Li2S, LiI, Li5P, Li4P2S6, and some unknown substances were detected in the interfacial layer by XRD.

  16. Tracing Waste Water with Li isotopes

    NASA Astrophysics Data System (ADS)

    Millot, R.; Desaulty, A. M.

    2015-12-01

    The contribution of human activities such as industries, agriculture and various domestic inputs, becomes more and more significant in the chemical composition of the dissolved load of rivers. Human factors act as a supplementary key process. Therefore the mass-balance for the budget of catchments and river basins include anthropogenic disturbances. In the present study, we investigate waste water tracing by the use of Li isotopes in a small river basin near Orléans in France (l'Egoutier, 15 km² and 5 km long). It is well known that Li has strategic importance for numerous industrial applications including its use in the production of batteries for both mobile devices (computers, tablets, smartphones, etc.) and electric vehicles, but also in pharmaceutical formulations. In the present work, we collected river waters samples before and after the release from a waste water treatment plant connected to an hospital. Lithium isotopic compositions are rather homogeneous in river waters with δ7Li values around -0.5‰ ± 1 along the main course of the stream (n=7). The waste water sample is very different from the natural background of the river basin with Li concentration being twice of the values without pollution and significant heavy lithium contribution (δ7Li = +4‰). These preliminary results will be discussed in relation with factors controlling the distribution of Li and its isotopes in this specific system and compared with the release of other metals such as Pb or Zn.

  17. LiGa(OTf)(sub 4) as an Electrolyte Salt for Li-Ion Cells

    NASA Technical Reports Server (NTRS)

    Reddy, V. Prakash; Prakash, G. K. Syria; Hu, Jinbo; Yan, Ping; Smart, Marshall; Bugga, ratnakumar; Chin, Keith; Surampudi, Subarao

    2008-01-01

    Lithium tetrakis(trifluoromethane sulfo - nato)gallate [abbreviated "LiGa(OTf)4" (wherein "OTf" signifies trifluoro - methanesulfonate)] has been found to be promising as an electrolyte salt for incorporation into both liquid and polymer electrolytes in both rechargeable and non-rechargeable lithium-ion electrochemical cells. This and other ingredients have been investigated in continuing research oriented toward im proving the performances of rechargeable lithium-ion electrochemical cells, especially at low temperatures. This research at earlier stages, and the underlying physical and chemical principles, were reported in numerous previous NASA Tech Briefs articles. As described in more detail in those articles, lithiumion cells most commonly contain nonaqueous electrolyte solutions consisting of lithium hexafluorophosphate (LiPF6) dissolved in mixtures of cyclic and linear alkyl carbonates, including ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), diethyl carbonate (DEC), and ethyl methyl carbonate (EMC). Although such LiPF6-based electrolyte solutions are generally highly ionically conductive and electrochemically stable, as needed for good cell performance, there is interest in identifying alternate lithium electrolyte salts that, relative to LiPF6, are more resilient at high temperature and are less expensive. Experiments have been performed on LiGa(OTf)4 as well as on several other candidate lithium salts in pursuit of this interest. As part of these experiments, LiGa(OTf)4 was synthesized by the reaction of Ga(OTf)3 with an equimolar portion of LiOTf in a solvent consisting of anhydrous acetonitrile. Evaporation of the solvent yielded LiGa(OTf)4 as a colorless crystalline solid. The LiGa(OTf)4 and the other salts were incorporated into solutions with PC and DMC. The resulting electrolyte solutions exhibited reasonably high ionic conductivities over a relatively wide temperature range down to 40 C (see figure). In cyclic

  18. The crystalline phases present in carbon cathodes of discharged Li/SOCl2-LiAlCl4 cells

    NASA Astrophysics Data System (ADS)

    Williams, R. M.; Surampudi, S.; Bankston, C. P.

    1989-05-01

    The X-ray diffraction patterns of 100 percent discharged Schawinigan black cathodes from Li/SOCl2-LiAlCl4 cells were obtained using a high resolution Guinier camera. The previous assignments of the diffraction lines to Li2O2 and rhombohedral sulfur are all found to be incorrect; all sharp Bragg diffraction lines not assignable to anhydrous LiCl can be assigned to LiCl.H2O.

  19. Li-7 abundances in halo stars: Testing stellar evolution models and the primordial Li-7 abundance

    NASA Technical Reports Server (NTRS)

    Chaboyer, Brian; Demarque, P.

    1994-01-01

    A large number of stellar evolution models with (Fe/H) = -2.3 and -3.3 have been calculated in order to determine the primordial Li-7 abundance and to test current stellar evolution models by a comparison to the extensive database of accurate Li abundances in extremely metal-poor halo stars observed by Thorburn (1994). Standard models with gray atmospheres do a very good job of fitting the observed Li abundances in stars hotter than approximately 5600 K. They predict a primordial. Li-7 abundance of log N(Li) = 2.24 +/- 0.03. Models which include microscopic diffusion predict a downward curvature in the Li-7 destruction isochrones at hot temperatures which is not present in the observations. Thus, the observations clearly rule out models which include uninhibited microscopic diffusion of Li-7 from the surface of the star. Rotational mixing inhibits the microscopic diffusion and the (Fe/H) = -2.28 stellar models which include both diffusion and rotational mixing provide an excellent match to the mean trend in T(sub eff) which is present in the observations. Both the plateau stars and the heavily depleted cool stars are well fit by these models. The rotational mixing leads to considerable Li-7 depletion in these models and the primordial Li-7 abundance inferred from these models is log N(Li) = 3.08 +/- 0.1. However, the (Fe/H) = -3.28 isochrones reveal problems with the combined models. These isochrones predict a trend of decreasing log N(Li) with increasing T(sub eff) which is not present in the observations. Possible causes for this discrepancy are discussed.

  20. Li-7 abundances in halo stars: Testing stellar evolution models and the primordial Li-7 abundance

    NASA Technical Reports Server (NTRS)

    Chaboyer, Brian; Demarque, P.

    1994-01-01

    A large number of stellar evolution models with (Fe/H) = -2.3 and -3.3 have been calculated in order to determine the primordial Li-7 abundance and to test current stellar evolution models by a comparison to the extensive database of accurate Li abundances in extremely metal-poor halo stars observed by Thorburn (1994). Standard models with gray atmospheres do a very good job of fitting the observed Li abundances in stars hotter than approximately 5600 K. They predict a primordial. Li-7 abundance of log N(Li) = 2.24 +/- 0.03. Models which include microscopic diffusion predict a downward curvature in the Li-7 destruction isochrones at hot temperatures which is not present in the observations. Thus, the observations clearly rule out models which include uninhibited microscopic diffusion of Li-7 from the surface of the star. Rotational mixing inhibits the microscopic diffusion and the (Fe/H) = -2.28 stellar models which include both diffusion and rotational mixing provide an excellent match to the mean trend in T(sub eff) which is present in the observations. Both the plateau stars and the heavily depleted cool stars are well fit by these models. The rotational mixing leads to considerable Li-7 depletion in these models and the primordial Li-7 abundance inferred from these models is log N(Li) = 3.08 +/- 0.1. However, the (Fe/H) = -3.28 isochrones reveal problems with the combined models. These isochrones predict a trend of decreasing log N(Li) with increasing T(sub eff) which is not present in the observations. Possible causes for this discrepancy are discussed.

  1. Li-Ion Battery with LiFePO4 Cathode and Li4Ti5O12 Anode for Stationary Energy Storage

    SciTech Connect

    Wang, Wei; Choi, Daiwon; Yang, Zhenguo

    2013-01-01

    i-ion batteries based on commercially available LiFePO4 cathode and Li4Ti5O12 anode were investigated for potential stationary energy storage applications. The full cell that operated at flat 1.85V demonstrated stable cycling for 200 cycles followed by a rapid fade. A significant improvement in cycling stability was achieved via Ketjen black coating of the cathode. A Li-ion full cell with Ketjen black modified LiFePO4 cathode and an unmodified Li4Ti5O12 anode exhibited negligible fade after more than 1200 cycles with a capacity of ~130mAh/g. The improved stability, along with its cost-effectiveness, environmentally benignity and safety, make the LiFePO4/ Li4Ti5O12 Li-ion battery a promising option of storing renewable energy.

  2. Structural and electrochemical stability of Li-rich layer structured Li2MoO3 in air

    NASA Astrophysics Data System (ADS)

    Ma, Jun; Gao, Yurui; Wang, Zhaoxiang; Chen, Liquan

    2014-07-01

    Li2MnO3 is an important component of the Li-rich Mn-based high-capacity cathode material for lithium ion batteries, xLi2MnO3·(1 - x)LiM‧O2 composites. Replacing Li2MnO3 with iso-structured Li2MoO3 is expected to improve the rate performance and suppress the oxygen release of the composites at high potentials due to the higher electric conductivity of Li2MoO3 and its more facile charge compensation (by Mo4+/Mo6+ redox) upon Li removal than that of Li2MnO3. As part of our series work on the Li2MoO3-based Li-rich layer structured cathode materials, this article is to study the structural and performance stability of Li2MoO3 in air. The obtained information will shed light on the development and application of xLi2MoO3·(1 - x)LiM‧O2 composite cathode materials though Li2MoO3 will not be applied as an independent cathode material.

  3. Synthesis and electrochemistry of cubic rocksalt Li-Ni-Ti-O compounds in the phase diagram of LiNiO 2-LiTiO 2-Li[Li 1/3Ti 2/3]O 2

    NASA Astrophysics Data System (ADS)

    Zhang, Lianqi; Noguchi, Hideyuki; Li, Decheng; Muta, Takahisa; Wang, Xiaoqing; Yoshio, Masaki; Taniguchi, Izumi

    On the basis of extreme similarity between the triangle phase diagrams of LiNiO 2-LiTiO 2-Li[Li 1/3Ti 2/3]O 2 and LiNiO 2-LiMnO 2-Li[Li 1/3Mn 2/3]O 2, new Li-Ni-Ti-O series with a nominal composition of Li 1+ z/3Ni 1/2- z/2Ti 1/2+ z/6O 2 (0 ≤ z ≤ 0.5) was designed and attempted to prepare via a spray-drying method. XRD identified that new Li-Ni-Ti-O compounds had cubic rocksalt structure, in which Li, Ni and Ti were evenly distributed on the octahedral sites in cubic closely packed lattice of oxygen ions. They can be considered as the solid solution between cubic LiNi 1/2Ti 1/2O 2 and Li[Li 1/3Ti 2/3]O 2 (high temperature form). Charge-discharge tests showed that Li-Ni-Ti-O compounds with appropriate compositions could display a considerable capacity (more than 80 mAh g -1 for 0.2 ≤ z ≤ 0.27) at room temperature in the voltage range of 4.5-2.5 V and good electrochemical properties within respect to capacity (more than 150 mAh g -1 for 0 ≤ z ≤ 0.27), cycleability and rate capability at an elevated temperature of 50 °C. These suggest that the disordered cubic structure in some cases may function as a good host structure for intercalation/deintercalation of Li +. A preliminary electrochemical comparison between Li 1+ z/3Ni 1/2- z/2Ti 1/2+ z/6O 2 (0 ≤ z ≤ 0.5) and Li 6/5Ni 2/5Ti 2/5O 2 indicated that charge-discharge mechanism based on Ni redox at the voltage of >3.0 V behaved somewhat differently, that is, Ni could be reduced to +2 in Li 1+ z/3Ni 1/2- z/2Ti 1/2+ z/6O 2 while +3 in Li 6/5Ni 2/5Ti 2/5O 2. Reduction of Ti 4+ at a plateau of around 2.3 V could be clearly detected in Li 1+ z/3Ni 1/2- z/2Ti 1/2+ z/6O 2 with 0.27 ≤ z ≤ 0.5 at 50 °C after a deep charge associated with charge compensation from oxygen ion during initial cycle.

  4. Observation and Analysis of LiCa and LiMg Excimers.

    DTIC Science & Technology

    1981-08-01

    Approved for public release: distribution unlimited Accession Fn7 NTIS GRA&I ( ’ DTIC T.AB , . Justifi -’ : _ ByDistributill/ AvnilVliitv Codcs...10 1. Molecular State Characterization ......................10 2. Electronic Transitions in Li~g and LiCa...11 E Energy ................... ............................16 R Internuclear Separation (A) ...........................16 T Electronic

  5. Excitation functions of {sup 6,7}Li+{sup 7}Li reactions at low energies

    SciTech Connect

    Prepolec, L.; Soic, N.; Blagus, S.; Miljanic, D.; Siketic, Z.; Skukan, N.; Uroic, M.; Milin, M.

    2009-08-26

    Differential cross sections of {sup 6,7}Li+{sup 7}Li nuclear reactions have been measured at forward angles (10 deg. and 20 deg.), using particle identification detector telescopes, over the energy range 2.75-10.00 MeV. Excitation functions have been obtained for low-lying residual-nucleus states. The well pronounced peak in the excitation function of {sup 7}Li({sup 7}Li,{sup 4}He){sup 10}Be(3.37 MeV,2{sup +}) at beam energy about 8 MeV, first observed by Wyborny and Carlson in 1971 at 0 deg., has been observed at 10 deg., but is less evident at 20 deg. The cross section obtained for the {sup 7}Li({sup 7}Li,{sup 4}He){sup 10}Be(g.s,0{sup +}) reaction is about ten times smaller. The well pronounced peak in the excitation function of {sup 7}Li({sup 7}Li,{sup 4}He){sup 10}Be(3.37 MeV,2{sup +}) reaction could correspond to excited states in {sup 14}C, at excitation energies around 30 MeV.

  6. Association and Diffusion of Li(+) in Carboxymethylcellulose Solutions for Environmentally Friendly Li-ion Batteries.

    PubMed

    Casalegno, Mosè; Castiglione, Franca; Passarello, Marco; Mele, Andrea; Passerini, Stefano; Raos, Guido

    2016-07-21

    Carboxymethylcellulose (CMC) has been proposed as a polymeric binder for electrodes in environmentally friendly Li-ion batteries. Its physical properties and interaction with Li(+) ions in water are interesting not only from the point of view of electrode preparation-processability in water is one of the main reasons for its environmental friendliness-but also for its possible application in aqueous Li-ion batteries. We combine molecular dynamics simulations and variable-time pulsed field gradient spin-echo (PFGSE) NMR spectroscopy to investigate Li(+) transport in CMC-based solutions. Both the simulations and experimental results show that, at concentrations at which Li-CMC has a gel-like consistency, the Li(+) diffusion coefficient is still very close to that in water. These Li(+) ions interact preferentially with the carboxylate groups of CMC, giving rise to a rich variety of coordination patterns. However, the diffusion of Li(+) in these systems is essentially unrestricted, with a fast, nanosecond-scale exchange of the ions between CMC and the aqueous environment. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Electrochemical behavior of Li/LiV3O8 secondary cells

    NASA Astrophysics Data System (ADS)

    Bak, Hyo Rim; Lee, Jae Ha; Kim, Bok Ki; Yoon, Woo Young

    2013-03-01

    Li/LiV3O8 secondary cells with Li-foil and Li-powder anodes were fabricated, and their electrical properties were compared. Using the powder anode, a cell with an initial discharge capacity of 260 mAh g-1 that could be operated for over 100 cycles was obtained. The porous Li-powder electrode was safely synthesized by pressing an emulsion droplet onto an SUS mesh. A threefold increase in the electrical conductivity of the LiV3O8 cathode was achieved by the addition of carbon using a vibration pot mill. Using the powder anode resulted in 80% capacity retention at the 100th cycle, while that using the foil electrode was 46%; the 1.0 Crate/ 0.1 C-rate capacity ratio also increased from 44% to 60%. A cell employing the LiV3O8-carbon composite cathode showed better electrical performance, a capacity retention of 90% after 50 cycles, and an increase in rate capacity ratio. The crystal structure and morphology of the LiV3O8-C composite were investigated by x-ray diffraction and scanning electron microscopy.

  8. Simulated electrolyte-metal interfaces -- Li3PO4 and Li

    NASA Astrophysics Data System (ADS)

    Xu, Xiao; Du, Yaojun A.; Holzwarth, N. A. W.

    2007-03-01

    There has recently been a lot of interest in solid electrolyte materials such as LiPON developed at Oak Ridge National Laboratory for use in Li-ion batteries and other technologies. We report on the results of our model calculations on idealized interfaces between Li3PO4 and Li metal, studying the structural stability and the ion mobility, using first-principles density functional techniques with the PWscf and pwpaw codes. Starting with a supercell constructed from Li3PO4 in its crystalline γ-phase structure and several layers of Li metal, we used optimization and molecular dynamics techniques to find several meta-stable configurations. The qualitative features of the results are consistent with experimental evidence that the electrolyte is quite stable with respect to Li metal. In addition to stability analyses, we plan to study Li-ion diffusion across the interface. J. B. Bates, N. J. Dudney, and co-workers, Solid State Ionics, 53-56, 647-654 (1992). http://www.pwscf.org and http://pwpaw.wfu.edu. N. J. Dudney in Gholam-Abbas Nazri and Gianfranco Pistoia, Eds., Lithium Batteries: Science and Technology, Chapt. 20, pp. 623-642, Kluwer Academic Publishers, 2004. ISBN 1-4020-7628-2.

  9. forced overdischarge related safety aspects of Li/SO2 and Li/SOCl2 cells

    NASA Technical Reports Server (NTRS)

    Abraham, K. M.

    1983-01-01

    Results of an experiment investigating overdischarge behavior of two types of Li/SO2 cells are presented. Forced overdischarges of the Li/LiBr, CH3CN/SO2 cell can result in unsafe behavior such as venting with fire and release of toxic gases. The hazards may be minimized or eliminated by careful cell design considerations and practice of high standards of quality contol in cell manufacture. Seemingly safe cells at 25 C when forced overdischarged at -25 C, even at low currents, exhibited incipient signs of hazards. Their cathodes indicated signs of shock sensitivity. Cathode limited Li/SOCl2 cells were safe during forced overdischarge for long periods of time. Lithium limited Li/SOCl2 cells in which practically all Li had been used up before cell reversal did not exhibit hazardous behavior. Anode limited Li/SOCl2 cells, but not Li limited, exhibited detonations, all during overdischarges at relatively low current densities of or = 1 mA/sq cm 2. Anode potentials 4v with large oscillations preceeded the events. The events were confined to the anode and the temperature rose high enough to melt Ni grids.

  10. Kinetic behavior of LiFeMgPO 4 cathode material for Li-ion batteries

    NASA Astrophysics Data System (ADS)

    Hong, Jian; Wang, Chunsheng; Kasavajjula, Uday

    LiFe 0.9Mg 0.1PO 4 material was prepared by mechanical milling method, followed by heat treatment. The equilibrium potential-composition isotherm of LiFe 0.9Mg 0.1PO 4 and charge-discharge kinetics of LiFe 0.9Mg 0.1PO 4 were measured using galvanostatic intermittent titration technique (GITT), potential-step chronoamperometry (PSCA), and electrochemical impedance spectroscopy (EIS). The rate performance of the cathode is controlled by the charge-transfer kinetics, electronic conductivity, Li-ion diffusion capability, and phase transformation rate. Since LiFe 0.9Mg 0.1PO 4 has a fast charge-transfer reaction and high electronic and ionic diffusivity, the phase transformation between LiFe 0.9Mg 0.1PO 4 and Li 0.1Fe 0.9Mg 0.1PO 4 begins to play a more important role in the charge-discharge process, as is evident by an inductive loop induced by the phase transformation in the low frequency region of EIS. The phase purity and morphology of LiFe 0.9Mg 0.1PO 4 were also observed using X-ray diffraction (XRD) and scanning electron microscopy (SEM).

  11. Cosmic Li6 and Li7 problems and BBN with long-lived charged massive particles

    NASA Astrophysics Data System (ADS)

    Jedamzik, Karsten

    2008-03-01

    Charged massive particles (CHAMPs), when present during the big bang nucleosynthesis (BBN) era, may significantly alter the synthesis of light elements when compared to a standard BBN scenario. This is due to the formation of bound states with nuclei. This paper presents a detailed numerical and analytical analysis of such CHAMP BBN. All reactions important for predicting light-element yields are calculated within the Born approximation. Three previously neglected effects are treated in detail: (a) photodestruction of bound states due to electromagnetic cascades induced by the CHAMP decay, (b) late-time efficient destruction/production of H2, Li6, and Li7 due to reactions on charge Z=1 nuclei bound to CHAMPs, and (c) CHAMP exchange between nuclei. Each of these effects may induce orders-of-magnitude changes in the final abundance yields. The study focuses on the impact of CHAMPs on a possible simultaneous solution of the Li6 and Li7 problems. It is shown that a previously suggested simultaneous solution of the Li6 and Li7 problems for a relic decaying at τx≈1000sec⁡ is only weakly dependent on the relic being neutral or charged, unless its hadronic branching ratio is small, Bh≪10-4. By use of a Monte Carlo analysis it is shown that within CHAMP BBN the existence of further parameter space for a simultaneous solution of the Li6 and Li7 problem for long decay times τx≳106sec⁡ seems possible but fairly unlikely.

  12. Interaction of water with LiCl, LiBr, and LiI in the deeply supercooled region.

    PubMed

    Souda, Ryutaro

    2007-12-07

    The hydration mechanism of lithium halides was studied using time-of-flight secondary ion mass spectrometry as a function of temperature. The lithium halides embedded in thin films of amorphous solid water segregate to the surface at temperatures higher than 135-140 K, with efficiency increasing in the order of LiCl, LiBr, and LiI. A monolayer of LiCl and LiI adsorbed on the surface of amorphous solid water tends to diffuse into the bulk at 160 K. The infrared absorption band revealed that the aqueous lithium-halide solutions and crystals are formed simultaneously at 160 K; these phenomena are explicable as a consequence of the evolution of supercooled liquid water. The strong surfactant effect is inferred to arise from hydration of a contact ion pair having hydrophilic (lithium) and hydrophobic (halide) moieties. Furthermore, bulk diffusion of lithium halides might result from the formation of a solvent-separated ion pair in supercooled liquid water. The presence of two liquid phases of water with different local structures is probably responsible for the formation of these two hydrates, consistent with the calculated result reported by Jungwirth and Tobias[J. Phys. Chem. B 106, 6361 (2002)].

  13. The first-principles study for the novel optical properties of LiTi2O4, Li4Ti5O12, Li2Ti2O4 and Li7Ti5O12

    NASA Astrophysics Data System (ADS)

    Liu, Yuxiang; Lian, Jie; Sun, Zhaozong; Zhao, Minglin; Shi, Yujun; Song, Haonan

    2017-06-01

    With the first-principles method based on the density functional theory (DFT), we studied novel optical properties of LiTi2O4, Li4Ti5O12, Li2Ti2O4 and Li7Ti5O12, respectively. According to the calculated electronic structures, the electron redistribution upon Li-ion intercalation has an obvious influence on the electronic transitions between O 2p and Ti 3d states, resulting in distinctions of optical properties between LiTi2O4, Li4Ti5O12, Li2Ti2O4 and Li7Ti5O12. These results not only reveal the fundamental origin of optical properties but also provide practical guidance on optical applications for these materials.

  14. A LiFSI-LiTFSI binary-salt electrolyte to achieve high capacity and cycle stability for a Li-S battery.

    PubMed

    Hu, J J; Long, G K; Liu, S; Li, G R; Gao, X P

    2014-12-04

    LiFSI and LiTFSI are combined to form a binary-salt electrolyte with higher ionic conductivity and lower viscosity for a Li-S battery. A high capacity and stable cycle performance of the sulfur-based composite with high sulfur content are realized in the electrolyte, accompanied simultaneously by the homogeneous lithium deposition on the anode.

  15. A design optimization methodology for Li+ batteries

    NASA Astrophysics Data System (ADS)

    Golmon, Stephanie; Maute, Kurt; Dunn, Martin L.

    2014-05-01

    Design optimization for functionally graded battery electrodes is shown to improve the usable energy capacity of Li batteries predicted by computational simulations and numerically optimizing the electrode porosities and particle radii. A multi-scale battery model which accounts for nonlinear transient transport processes, electrochemical reactions, and mechanical deformations is used to predict the usable energy storage capacity of the battery over a range of discharge rates. A multi-objective formulation of the design problem is introduced to maximize the usable capacity over a range of discharge rates while limiting the mechanical stresses. The optimization problem is solved via a gradient based optimization. A LiMn2O4 cathode is simulated with a PEO-LiCF3SO3 electrolyte and both a Li Foil (half cell) and LiC6 anode. Studies were performed on both half and full cell configurations resulting in distinctly different optimal electrode designs. The numerical results show that the highest rate discharge drives the simulations and the optimal designs are dominated by Li+ transport rates. The results also suggest that spatially varying electrode porosities and active particle sizes provides an efficient approach to improve the power-to-energy density of Li+ batteries. For the half cell configuration, the optimal design improves the discharge capacity by 29% while for the full cell the discharge capacity was improved 61% relative to an initial design with a uniform electrode structure. Most of the improvement in capacity was due to the spatially varying porosity, with up to 5% of the gains attributed to the particle radii design variables.

  16. The Effects of Li/Nb Ratio on the Preparation and Photocatalytic Performance of Li-Nb-O Compounds.

    PubMed

    Zhai, Haifa; Liu, Hairui; Li, Hongjing; Zheng, Liuyang; Hu, Chunjie; Wang, Zhao; Qi, Jingjing; Yang, Jien

    2017-08-15

    The effects of Li/Nb ratio on the preparation of Li-Nb-O compounds by a hydrothermal method were studied deeply. Li/Nb ratio has a great impact on the formation of LiNbO3; the ratio smaller than 3:1 is beneficial to the formation of LiNbO3, while larger than 3:1, forms no LiNbO3 at all and the morphology and chemical bond of Nb2O5 raw material are totally modified by Li ions. The reason can be attributed to the large content of LiOH, which is beneficial to form Li3NbO4 not LiNbO3, and also, even if LiNbO3 particle locally forms, it is easily dissolved in LiOH solution with strong alkalinity. Pure LiNb3O8 powders are obtained with two absolutely opposite Li/Nb ratios: 8:1 and 1:3; the former shows a unique porous and hollow structure, quite different from the particle aggregation (the latter shows). Compared with Li/Nb = 1:3, the 4.2 times higher photocatalytic performance of LiNb3O8 (Li/Nb = 8:1) are observed and it can be attributed to the unique porous and hollow structure, which provides a high density of active sites for the degradation of MB. Compared to LiNbO3, the improved photocatalytic performance of LiNb3O8 can be attributed to its layered structure type with the reduced symmetry enhancing the separation of electrons and holes.

  17. The Effects of Li/Nb Ratio on the Preparation and Photocatalytic Performance of Li-Nb-O Compounds

    NASA Astrophysics Data System (ADS)

    Zhai, Haifa; Liu, Hairui; Li, Hongjing; Zheng, Liuyang; Hu, Chunjie; Wang, Zhao; Qi, Jingjing; Yang, Jien

    2017-08-01

    The effects of Li/Nb ratio on the preparation of Li-Nb-O compounds by a hydrothermal method were studied deeply. Li/Nb ratio has a great impact on the formation of LiNbO3; the ratio smaller than 3:1 is beneficial to the formation of LiNbO3, while larger than 3:1, forms no LiNbO3 at all and the morphology and chemical bond of Nb2O5 raw material are totally modified by Li ions. The reason can be attributed to the large content of LiOH, which is beneficial to form Li3NbO4 not LiNbO3, and also, even if LiNbO3 particle locally forms, it is easily dissolved in LiOH solution with strong alkalinity. Pure LiNb3O8 powders are obtained with two absolutely opposite Li/Nb ratios: 8:1 and 1:3; the former shows a unique porous and hollow structure, quite different from the particle aggregation (the latter shows). Compared with Li/Nb = 1:3, the 4.2 times higher photocatalytic performance of LiNb3O8 (Li/Nb = 8:1) are observed and it can be attributed to the unique porous and hollow structure, which provides a high density of active sites for the degradation of MB. Compared to LiNbO3, the improved photocatalytic performance of LiNb3O8 can be attributed to its layered structure type with the reduced symmetry enhancing the separation of electrons and holes.

  18. Characteristic of Absorption Heat Transfer using LiBr+LiI Solution

    NASA Astrophysics Data System (ADS)

    Tsujimori, Atsushi; Ozaki, Eiichi; Nakao, Kazushige

    LiBr-H20 absorption chiller is widely used in Japan, and many research have been made for absorption characteristic in terms of enhancing heat transfer. Another study have been performed for widening working range with higher crystallization limits, and it was reported that adding LiI salt to LiBr-H20 working fluid provide about 5 [mass%] higher crystallization limit under the condition of absorption pressure range. It is necessary to reveal absorption heat transfer performance to utilize this working fluid pair for absorption chiller. In this study absorption heat transfer characteristic was investigated for horizontal and vertical tube. As a result, it was found that heat transfer coefficient increased as mass flow rate of solution increased and mass concentration of solution decrease and that these characteristic were almost the same as LiBr solution, though this solution gave slightly less heat transfer coefficient than LiBr solution.

  19. Structures of NADH and CH[subscript 3]-H[subscript 4] Folate Complexes of Escherichia coli Methylenetetrahydrofolate Reductase Reveal a Spartan Strategy for a Ping-Pong Reaction

    SciTech Connect

    Pejchal, Robert; Sargeant, Ryan; Ludwig, Martha L.

    2010-03-08

    Methylenetetrahydrofolate reductases (MTHFRs; EC 1.7.99.5) catalyze the NAD(P)H-dependent reduction of 5,10-methylenetetrahydrofolate (CH{sub 2}-H{sub 4}folate) to 5-methyltetrahydrofolate (CH{sub 3}-H{sub 4}folate) using flavin adenine dinucleotide (FAD) as a cofactor. The initial X-ray structure of Escherichia coli MTHFR revealed that this 33-kDa polypeptide is a ({beta}{alpha}){sub 8} barrel that aggregates to form an unusual tetramer with only 2-fold symmetry. Structures of reduced enzyme complexed with NADH and of oxidized Glu28Gln enzyme complexed with CH{sub 3}-H{sub 4}folate have now been determined at resolutions of 1.95 and 1.85 {angstrom}, respectively. The NADH complex reveals a rare mode of dinucleotide binding; NADH adopts a hairpin conformation and is sandwiched between a conserved phenylalanine, Phe223, and the isoalloxazine ring of FAD. The nicotinamide of the bound pyridine nucleotide is stacked against the si face of the flavin ring with C4 adjoining the N5 of FAD, implying that this structure models a complex that is competent for hydride transfer. In the complex with CH{sub 3}-H{sub 4}folate, the pterin ring is also stacked against FAD in an orientation that is favorable for hydride transfer. Thus, the binding sites for the two substrates overlap, as expected for many enzymes that catalyze ping-pong reactions, and several invariant residues interact with both folate and pyridine nucleotide substrates. Comparisons of liganded and substrate-free structures reveal multiple conformations for the loops {beta}2-{alpha}2 (L2), {beta}3-{alpha}3 (L3), and {beta}4-{alpha}4 (L4) and suggest that motions of these loops facilitate the ping-pong reaction. In particular, the L4 loop adopts a 'closed' conformation that allows Asp120 to hydrogen bond to the pterin ring in the folate complex but must move to an 'open' conformation to allow NADH to bind.

  20. Effect of Li/Nb Ratio on Growth and Spectrometric Characterization of Hf:Fe:LiNbO3 Crystals

    NASA Astrophysics Data System (ADS)

    Dai, Li; Wu, Shi-Ping; Guo, Jing-Jie; Xu, Chao; Su, Yan-Qing; Xu, Yu-Heng

    Hf:Fe:LiNbO3 crystals were grown by the Czochralski technique with various ratios of Li/Nb = 0.946, 1.05, 1.20 and 1.38 in the melt. The crystal composition and defect structure were analyzed by XRD, UV-Vis and IR spectroscopy. The results show that the threshold concentration of Hf in LiNbO3 crystals decrease with the increasing of the Li/Nb ratio; when the Li/Nb ratio is 1.05, the threshold concentration of Hf is less than 2 mol%, largely under the threshold concentration of Hf ions in congruent Hf:Fe:LiNbO3 crystal (4 mol).1-3 With the increase of Li/Nb, Hf ions first replace the Nb4+ Li; when the concentration of Hf ions is higher than the threshold value, Hf ions occurs on normal Nb and Li sites.

  1. Li-FSI Impurity Impact Study: Final CRADA Report

    SciTech Connect

    Pupek, Krzysztof; Dzwiniel, Trevor; Krumdick, Gregory

    2017-01-01

    There is growing interest in lithium bis(fluorosulfonyl)imide (LiFSI ) as an alternative to LiPF6 and as an additive to electrolytes used in lithium-ion cells. LiFSI has attracted attention because it is reported to have higher ionic conductivity, better high temperature stability, and enhanced stability toward hydrolysis, Also, LiFSI additive to electrolytes can bring benefits of improved storage properties and reduced gas evolution in the cells. Different levels of different electrochemically active impurities could affect the performance of LiFSI as an electrolyte salt for Li-ion batteries, generating inconsistent and conflicting interpretations of the experimental data.

  2. Electrolytes in Support of 5V Li-ion Batteries

    DTIC Science & Technology

    2010-12-16

    OF: a. REPORT b. ABSTRACT c . THIS PAGE 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON...candidates LiCoPO4, LiNi0.5Mn1.5O4, Li2FeCoPO4 etc, projected to deliver 15~40% more energy than state-of-art LiFePO4 The additive invented by SEDD is...battery pack for HEV as example: 300 V hybrid electric system • requires at least 100 LiFePO4 Li ion cells in series • power electronics, protection

  3. Suppressing The Growth Of Dendrites In Secondary Li Cells

    NASA Technical Reports Server (NTRS)

    Davies, Evan D.; Perrone, David E.; Shen, David H.

    1996-01-01

    Proposed technique for suppressing growth of lithium dendrites in rechargeable lithium electrochemical power cells involves periodic interruption of steady charging current with short, high-current discharge pulses. Technique applicable to lithium cells of several different types, including Li/TiS(2), Li/NbSe(3), Li/CoO(2), Li/MoS(2), Li/Vo(x), and Li/MnO(2). Cells candidates for use in spacecraft, military, communications, automotive, and other applications in which high-energy-density rechargeable batteries needed.

  4. Composition gradients in electrolyzed LiCl-KCl eutectic melts

    NASA Astrophysics Data System (ADS)

    Vallet, C. E.; Heatherly, D. E.; Braunstein, J.

    1983-12-01

    Analysis of transport in a mixed electrolyte has previously predicted significant composition gradients in the LiCl-KCl electrolyte of high temperature LiS/ batteries. Composition gradients in quenched electrolyzed LiCl-KCl eutectic contained in yttria felt are measured with high distance resolution by scanning electron microscopy with energy dispersive X-ray spectroscopy. The reported results include composition profiles of LiCl-KCl coontained in porous Y2O3 and electrolyzed in three cells, two with solid Li-Al electrodes and one with a porous Li-Al anode.

  5. Anharmonicity and phase stability of antiperovskite Li3OCl

    NASA Astrophysics Data System (ADS)

    Chen, Min-Hua; Emly, Alexandra; Van der Ven, Anton

    2015-06-01

    A lattice-dynamics study of the cubic Li3OCl antiperovskite, a candidate solid electrolyte in lithium-ion batteries, reveals the presence of dynamical instabilities with respect to rotations of the Li6O octahedra. Calculated energy landscapes in the subspace of unstable octahedral rotational modes are very shallow with at most a 1 meV per formula unit reduction in energy upon breaking the cubic symmetry. While Li3OCl is not stable relative to decomposition into Li2O and LiCl at 0 K, estimates of the vibrational free energy suggest that Li3OCl antiperovskite should become entropically stabilized above approximately 480 K.

  6. Theory of laser enhancement and suppression of cold reactions: the fermion-boson 6Li+7Li2<-->(variant Planck's over 2pi omega0) 6Li7Li+7Li radiative collision.

    PubMed

    Li, Xuan; Parker, Gregory A; Brumer, Paul; Thanopulos, Ioannis; Shapiro, Moshe

    2008-03-28

    We present a nonperturbative time-dependent quantum mechanical theory of the laser catalysis and control of a bifurcating A+BC<-->(variant Planck's over 2pi omega(0))ABC*(v)<-->(variant Planck's over 2pi omega(0) )AB+C reaction, with ABC*(v) denoting an intermediate, electronically excited, complex of ABC in the vth vibrational state. We apply this theory to the low collision energy fermion-boson light-induced exchange reaction, (6)Li((2)S)+(7)Li(2)((3)Sigma(u)(+))<-->(variant Planck's over 2pi omega(0))((6)Li(7)Li(7)Li)*<-->(variant Planck's over 2pi omega(0))(6)Li(7)Li((3)Sigma(+))+(7)Li((2)S). We show that at very low collision energies and energetically narrow (approximately 0.01 cm(-1)) initial reactant wave packets, it is possible to tune the yield of the exchange reaction from 0 to near-unity (yield >or=99%) values. Controllability is somewhat reduced at collisions involving energetically wider (approximately 1 cm(-1)) initial reactant wave packets. At these energetic bandwidths, the radiative reactive control, although still impressive, is limited to the 0%-76% reactive-probabilities range.

  7. Thermodynamic optimization of the Li-Pb system aided by first-principles calculations

    NASA Astrophysics Data System (ADS)

    Zhou, Chenyang; Guo, Cuiping; Li, Changrong; Du, Zhenmin

    2016-08-01

    The Li-Pb system was optimized using CALPHAD (CALculation of PHAse Diagram) method. The enthalpies of formation of eight intermetallic compounds Li4Pb (Li22Pb5), Li7Pb2, Li10Pb3, Li3Pb, Li8Pb3, Li5Pb2, αLiPb and βLiPb at 0 K were calculated from first-principles calculations with DFT + GGA approximations. The liquid phase was treated as (Li,Li0.8Pb0.2,Pb) using an associated solution model because a short-range-order phenomenon was proven to exist in liquid. The solution phases fcc and bcc were described as (Li,Pb) with a simple substitutional model. The intermetallic compounds Li4Pb, Li3Pb and Li5Pb2 were treated as stoichiometric compounds. With certain solubility ranges, the intermetallic compounds Li7Pb2, αLiPb and βLiPb were modeled as Li7(Li,Pb)2, (Li,Pb)(Li,Pb) and (Li,Pb)(Li,Pb) using the two-sublattice model. A set of self-consistent thermodynamic parameters in the Li-Pb system was obtained in the present work.

  8. Development of overcharge tolerance in Li/FeS and Li/FeS/sub 2/ cells

    SciTech Connect

    Kaun, T.D.; Holifield, T.F.; Nigohosian, M.; Nelson, P.A.

    1988-01-01

    An innovative application of a self-discharge mechanism for molten-electrolyte Li-alloy/FeS/sub x/ cells has led to the development of overcharge-tolerant cells. Conventional Li-alloy/FeS/sub x/ battery cells require an electronic charger/equalizer. Two versions of the cell have been demonstrated: LiAl+10 Mol% Li/sub 5/Al/sub 5/Fe/sub 2//LiCl-LiBr-KBr (BN, MgO)/FeS/sub 2/ (operated at 400/degree/C) and LiAl+10 mol% Li/sub 5/Fe/sub 2//LiF-LiCl-LiBr(MgO)/FeS (operated at 475/degree/C). These cells exhibit a unique combination of overcharge capacity and extended trickle-charge tolerance at 2--5 mA/cm/sup 2/. The basis for the self-discharge is diffusion of reduced lithium species across the separator by a lithium-shuttle mechanism that is controlled by the Li-activity of the Li-alloy electrode. A bimodal self-discharge rate (a 20-fold increase toward the end of charge) results from a 150--250 mV step increase in Li-activity. Cells having overcharge tolerance have operated with stable performance for greater than 200 cycles. The overcharge tolerance rates are sufficient for battery cells to exhibit built-in charge/equalization capability. 11 refs., 6 figs.

  9. Quantitative analysis of Li by PIGE technique

    NASA Astrophysics Data System (ADS)

    Fonseca, M.; Mateus, R.; Santos, C.; Cruz, J.; Silva, H.; Luis, H.; Martins, L.; Jesus, A. P.

    2017-09-01

    In this work, the cross section of the reactions 7Li(p,pγ)7Li (γ - 478 keV) at the proton energy range 2.0-4.2 MeV was measured. The measurements were carried out at the 3 MV Tandem Accelerator at the CTN/IST Laboratory in Lisbon. To validate the obtained results, calculated gamma-ray yields were compared, at several proton energy values, with experimental yields for thick samples made of inorganic compounds containing lithium. In order to quantify the light elements present in the samples, we used a standard free method for PIGE in thick samples, based on a code - Emitted Radiation Yield Analysis (ERYA), which integrates the nuclear reaction excitation function along the depth of the sample. We also demonstrated the capacity of the technique for analysis of Li ores, as Spodumene, Lithium Muscovite and Holmquistite, and Li-alloys for plasma facing materials showing that this is a reliable and accurate method for PIGE analysis of Li in thick samples.

  10. Formation and reduction behaviors of zirconium oxide compounds in LiCl-Li2O melt at 923 K

    NASA Astrophysics Data System (ADS)

    Sakamura, Yoshiharu; Iizuka, Masatoshi; Kitawaki, Shinichi; Nakayoshi, Akira; Kofuji, Hirohide

    2015-11-01

    The reduction behaviors of ZrO2, Li2ZrO3 and (U,Pu,Zr)O2 in a LiCl-Li2O salt bath at 923 K were investigated. This study was conducted as part of a feasibility study on the pyrochemical treatment of damaged fuel debris generated by severe accidents at light water reactors. It was demonstrated in electrolytic reduction tests that the uranium in synthetic corium specimens of (U,Pu,Zr)O2 with various ZrO2 contents could be reduced to the metallic form and that part of the zirconium was converted to Li2ZrO3. Zirconium metal and Li2ZrO3 were obtained by the reduction of ZrO2. The reduction of Li2ZrO3 did not proceed even in LiCl containing no Li2O. Moreover, the stable chemical forms of the ZrO2-Li2O complex oxide were investigated as a function of the Li2O concentration in LiCl. ZrO2 was converted to Li2ZrO3 at a Li2O concentration of 0.018 wt%. As the Li2O concentration was increased, Li2ZrO3 was converted to Li6Zr2O7 and then to Li8ZrO6. It is suggested that the removal of Li2ZrO3 from the reduction product is a key point in the pyrochemical treatment of corium.

  11. Computational Studies of Solubilities of LiO2 and Li2O2 in Aprotic Solvents

    DOE PAGES

    Cheng, Lei; Redfern, Paul; Lau, Kah Chun; ...

    2017-08-12

    Knowledge of the solubilities of Li2O2 and LiO2 in aprotic solvents is important for insight into the discharge and charge processes of Li-O2 batteries, but these quantities are not well known. In this contribution, the solvation free energies of molecular LiO2 and Li2O2 in various organic solvents were calculated using various explicit and implicit solvent models, as well as ab initio molecular dynamics (AIMD) methods. Best estimates for the solvation energies from these calculations along with calculated lattice energies of Li2O2 and LiO2 were used to determine the solubility of bulk LiO2 and Li2O2. The computed solubility of LiO2 (1.8more » × 10-2 M) is about 15 orders higher than that of Li2O2 (2.0 × 10-17 M) due to a much less negative lattice energy of bulk LiO2 compared to that of Li2O2. The difference in solubilities between LiO2 and Li2O2 likely will affect the nucleation and growth mechanisms and resulting morphologies of the products formed during battery discharge, influencing the performance of the battery cell. In conclusion, the calculated LiO2 and Li2O2 solubilities provide important information for fundamental studies of discharge and charge chemistries in Li-O2 batteries.« less

  12. Corrosion studies of LiH thin films

    NASA Astrophysics Data System (ADS)

    Tonks, J. P.; King, M. O.; Galloway, E. C.; Watts, J. F.

    2017-02-01

    Thin films of LiH and its corrosion products were studied using temperature programmed decomposition (TPD), x-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). Thin films were grown on Ni(100) in an ultra high vacuum system using an electron beam evaporator. Characteristic Li KLL AES peaks were identified for Li, LiH, Li2O and LiOH which facilitated identification of thin film composition. XPS of the O 1s region revealed three distinct chemical shifts which were attributed to Li2O, LiOH and chemisorbed H2O. We show that exposing LiH to very low H2O partial pressures results in formation of LiOH/Li2O domains on LiH. We also show that these XPS peaks can be linked to reaction mechanisms in the TPD profiles. TPD traces have been explicitly modelled to determine the activation energies of the reactions and compare favourably with previous measurements on bulk LiH samples.

  13. Enhanced electrochemical performance of Li-rich cathode Li[Li0.2Mn0.54Ni0.13Co0.13]O2 by surface modification with lithium ion conductor Li3PO4

    NASA Astrophysics Data System (ADS)

    Wang, Zhiyuan; Luo, Shaohua; Ren, Jie; Wang, Dan; Qi, Xiwei

    2016-05-01

    Li-rich layered cathode Li[Li0.2Mn0.54Ni0.13Co0.13]O2 is prepared via a co-precipitation followed with high-temperature calcination, and then successfully modified with nano-Li3PO4 by ball milling and annealing. The TEM and EDS reveal that Li3PO4 is homogeneously coated on the particle surface of Li[Li0.2Mn0.54Ni0.13Co0.13]O2. And the electrochemical performance of Li[Li0.2Mn0.54Ni0.13Co0.13]O2 is significantly improved by coating with lithium ion conductor Li3PO4. The Li3PO4-coated sample delivers a high initial discharge capacity of 284.7 mAhg-1 at 0.05 C, and retains 192.6 mAhg-1 after 100 cycles at 0.5 C, which is higher than that of the pristine sample (244 mAhg-1 at 0.05 C and 168.2 mAhg-1 after 100 cycles at 0.5 C). The electrochemical impedance spectroscopy (EIS) demonstrates that the resistance for Li/Li3PO4-coated Li[Li0.2Mn0.54Ni0.13Co0.13]O2 cell was reduced compared to Li/Li[Li0.2Mn0.54Ni0.13Co0.13]O2, which indicates the Li3PO4 coating layer with high ionic conductivity (6.6 × 10-8 S cm-1) facilitates the diffusion of lithium ions through the interface between electrode and electrolyte and accelerates the charge transfer process. What is more, the Li3PO4 coating layer can also act as a protection layer to protect the cathode material from encroachment of electrolyte. The two aspects account for the enhanced electrochemical performance of Li3PO4-coated Li[Li0.2Mn0.54Ni0.13Co0.13]O2.

  14. Li14P2O3N6 and Li7PN4: Computational study of two nitrogen rich crystalline LiPON electrolyte materials

    NASA Astrophysics Data System (ADS)

    Al-Qawasmeh, Ahmad; Holzwarth, N. A. W.

    2017-10-01

    Two lithium oxonitridophosphate materials are computationally examined and found to be promising solid electrolytes for possible use in all solid-state batteries having metallic Li anodes - Li14P2O3N6 and Li7PN4. The first principles simulations are in good agreement with the structural analyses reported in the literature for these materials and the computed total energies indicate that both materials are stable with respect to decomposition into binary and ternary products. The computational results suggest that both materials are likely to form metastable interfaces with Li metal. The simulations also find both materials to have Li ion migration activation energies comparable or smaller than those of related Li ion electrolyte materials. Specifically, for Li7PN4, the experimentally measured activation energy can be explained by the migration of a Li ion vacancy stabilized by a small number of O2- ions substituting for N3- ions. For Li14P2O3N6, the activation energy for Li ion migration has not yet been experimentally measured, but simulations predict it to be smaller than that measured for Li7PN4.

  15. Neutron scattering studies of glassy Li+ superionics

    NASA Astrophysics Data System (ADS)

    Heitmann, Tom; Zella, Leo; Zaidi, Ali; Rathore, Munesh; Dalvi, Anshuman; Mitra, Saibal

    2013-03-01

    Two distinct neutron scattering techniques were implemented in the study of glassy superionic materials composed of a complex network of their interconnected sub-units: Li2O, NH4H2PO2, and Li2SO4. The use of disordered materials underlies an effort to promote Li+ mobility, while suppressing e- conductivity, which makes them good candidates for use as electrolytes in lithium ion batteries. We present triple-axis spectrometer results of energy resolved vs. energy integrated neutron scattering that indicate the presence of a broad range of dynamic processes in the materials, rather than well-defined excitations. Additionally, we report on neutron diffraction data that demonstrates the formation of crystallites within the material upon annealing up to 450 °C. Such crystallites hinder the performance of the materials as electrolytes, which is evident in thin film devices where heating is unavoidable during fabrication.

  16. Re-evaluation of the eutectic region of the LiBr-KBr-LiF system

    SciTech Connect

    Redey, L.; Guidotti, R.A.

    1996-05-01

    The separator pellet in a thermal battery consists of electrolyte immobilized by a binder (typically, MgO powder). The melting point of the electrolyte determines the effective operating window for its use in a thermal battery. The development of a two-hour thermal battery required the use of a molten salt that had a lower melting point and larger liquidus range than the LiCl-KCl eutectic which melts at 352 C. Several candidate eutectic electrolyte systems were evaluated for their suitability for this application. One was the LiCl-LiBr-KBr eutectic used at Argonne National Laboratories for high-temperature rechargeable batteries for electric-vehicle applications. Using a custom-designed high-temperature conductivity cell, the authors were able to readily determine the liquidus region for the various compositions studied around the original eutectic for the LiBr-KBr-LiF system. The actual eutectic composition was found to be 60.0 m/o LiBr-37.5 m/o KBr-2.5 m/o LiF with a melting point of 324 {+-} 0.5 C.

  17. Long-lived states of antiprotonic lithium pLi {sup +} produced in p+ Li collisions

    SciTech Connect

    Sakimoto, Kazuhiro

    2011-09-15

    Antiproton capture by lithium atoms (p+Li{yields}pLi{sup +}+e) is investigated at collision energies from 0.01 to 10 eV by using a semiclassical (also know as quantum-classical hybrid) method, in which the radial distance between the antiproton and the Li{sup +} ion is treated as a classical variable, and the other degrees of freedom are described by quantum mechanics. Analyzing the wave packet of the emitted electrons and making use of the energy conservation rule enable us to calculate the state distribution of the produced antiprotonic lithium pLi{sup +} atoms and also to distinguish between the capture and ionization ({yields}p+Li{sup +}+e) channels at collisional energies above the ionization threshold. This method is tested for the capture of negative muons by hydrogen atoms, which was rigorously investigated in previous quantum mechanical studies. Most of the pLi{sup +} atoms produced in p+Li are found to be sufficiently stable against Auger decays and are experimentally observable as long-lived states. The present system bears close similarities to the system of p+He(2S). It is therefore expected that long-lived antiprotonic helium pHe{sup +} atoms can be efficiently produced in the p capture by metastable He(2 {sup 3}S) atoms.

  18. Analyzing Powers of (^6 Li,d) Reactions and the D State of ^6Li.

    NASA Astrophysics Data System (ADS)

    Veal, K. D.; Brune, C. R.; Geist, W. H.; Karwowski, H. J.; Ludwig, E. J.; Mendez, A. J.; Kozlowska, B.; Bartosz, E. E.; Cathers, P. D.; Drummer, T. L.; Kemper, K. W.; Eiró, A. M.; Santos, F. D.; Thompson, I. J.

    1997-10-01

    One way to quantify the D-state component of a light nucleus is in terms of η, the ratio of the D and S state asymptotic normalization constants. Calculations of tensor analyzing powers of transfer reactions induced by polarized ^6Li ions show considerable sensitivity to the magnitude and sign of η(^6Li). To this end, we have made measurements of the analyzing powers A_y, A_zz, and A_xz for the 0^+ gs and the lowest 2^+ state from (^6Li,d) reactions on ^58Ni and ^40Ca at E(^6Li) = 34 MeV. We have performed DWBA calculations that are in good agreement with the cross section and Ay data. Treating η(^6Li) as the only remaining adjustable fitting parameter, we have calculated a best fit value of η(^6Li) for each of the tensor analyzing power angular distributions. Preliminary estimates showing η(^6Li) to be smaller than previous determinations(D.R. Lehman, Colloque de Physique Suppl. n 22, 51), C6-47 (1990). will be presented.

  19. Radiative Association in Li+ + H- collisions

    NASA Astrophysics Data System (ADS)

    Dickinson, A. S.; Gadéa, F. X.

    Radiative association is one of the ways of forming LiH in low density environments. Its formation in collisions of Li(2p) +H(1s) has been shown to be about five orders of magnitude faster than for Li(2s) + H(1s) [1]. We investigate LiH formation in Li+ + H- collisions, considering association on both the C and D Σ states as about 96% of the mutual neutralization is to these states at low energy [2]. A quantal description of the process [3] has been used. The potentials are from ref. [4] and the dipole moments from ref. [5]. Similar results were obtained from both the C and D states. At 1000 K the total radiative association rate coefficient from the D state is 9.2× 10-15 cm3/s, compared to 2.1 × 10-20 cm3/s in Li(2s) + H(1s) collisions [6]. British Council support is gratefully acknowledged. {[1]} Gianturco F.A., Gori Giorgi P., 1996, Phys. Rev. A 54, 4073 {[2]} Croft H., Dickinson A.S., Gadéa F. X., 1999, MNRAS 304, 327 {[3]} Babb J.F., Kirby K.P., 1998, in The Molecular Astrophysics of Stars and Galaxies, Clarendon Press, Oxford, p. 11 {[4]} Gadéa F. X., Boutalib A., 1993, J. Phys. B 26, 61 {[5]} Berriche H., Gadéa F. X., 1995, Chem. Phys. Letts. 247 85 {[6]} Stancil P. C., Dalgarno A., 1997, ApJ 479, 543

  20. NASA Goddards LiDAR, Hyperspectral and Thermal (G-LiHT) Airborne Imager

    NASA Technical Reports Server (NTRS)

    Cook, Bruce D.; Corp, Lawrence A.; Nelson, Ross F.; Middleton, Elizabeth M.; Morton, Douglas C.; McCorkel, Joel T.; Masek, Jeffrey G.; Ranson, Kenneth J.; Ly, Vuong; Montesano, Paul M.

    2013-01-01

    The combination of LiDAR and optical remotely sensed data provides unique information about ecosystem structure and function. Here, we describe the development, validation and application of a new airborne system that integrates commercial off the shelf LiDAR hyperspectral and thermal components in a compact, lightweight and portable system. Goddard's LiDAR, Hyperspectral and Thermal (G-LiHT) airborne imager is a unique system that permits simultaneous measurements of vegetation structure, foliar spectra and surface temperatures at very high spatial resolution (approximately 1 m) on a wide range of airborne platforms. The complementary nature of LiDAR, optical and thermal data provide an analytical framework for the development of new algorithms to map plant species composition, plant functional types, biodiversity, biomass and carbon stocks, and plant growth. In addition, G-LiHT data enhance our ability to validate data from existing satellite missions and support NASA Earth Science research. G-LiHT's data processing and distribution system is designed to give scientists open access to both low- and high-level data products (http://gliht.gsfc.nasa.gov), which will stimulate the community development of synergistic data fusion algorithms. G-LiHT has been used to collect more than 6,500 km2 of data for NASA-sponsored studies across a broad range of ecoregions in the USA and Mexico. In this paper, we document G-LiHT design considerations, physical specifications, instrument performance and calibration and acquisition parameters. In addition, we describe the data processing system and higher-level data products that are freely distributed under NASA's Data and Information policy.

  1. Asymptotic and near-target direct breakup of 6Li and 7Li

    NASA Astrophysics Data System (ADS)

    Kalkal, Sunil; Simpson, E. C.; Luong, D. H.; Cook, K. J.; Dasgupta, M.; Hinde, D. J.; Carter, I. P.; Jeung, D. Y.; Mohanto, G.; Palshetkar, C. S.; Prasad, E.; Rafferty, D. C.; Simenel, C.; Vo-Phuoc, K.; Williams, E.; Gasques, L. R.; Gomes, P. R. S.; Linares, R.

    2016-04-01

    Background: Li,76 and 9Be are weakly bound against breakup into their cluster constituents. Breakup location is important for determining the role of breakup in above-barrier complete fusion suppression. Recent works have pointed out that experimental observables can be used to separate near-target and asymptotic breakup. Purpose: Our purpose is to distinguish near-target and asymptotic direct breakup of Li,76 in reactions with nuclei in different mass regions. Method: Charged particle coincidence measurements are carried out with pulsed Li,76 beams on 58Ni and 64Zn targets at sub-barrier energies and compared with previous measurements using 208Pb and 209Bi targets. A detector array providing a large angular coverage is used, along with time-of-flight information to give definitive particle identification of the direct breakup fragments. Results: In interactions of 6Li with 58Ni and 64Zn, direct breakup occurs only asymptotically far away from the target. However, in interactions with 208Pb and 209Bi, near-target breakup occurs in addition to asymptotic breakup. Direct breakup of 7Li into α -t is not observed in interactions with 58Ni and 64Zn. However, near-target dominated direct breakup was observed in measurements with 208Pb and 209Bi. A modified version of the Monte Carlo classical trajectory model code platypus, which explicitly takes into account lifetimes associated with unbound states, is used to simulate sub-barrier breakup reactions. Conclusions: Near-target breakup in interactions with Li,76 is an important mechanism only for the heavy targets 208Pb and 209Bi. There is insignificant near-target direct breakup of 6Li and no direct breakup of 7Li in reactions with 58Ni and 64Zn. Therefore, direct breakup is unlikely to suppress the above-barrier fusion cross section in reactions of Li,76 with 58Ni and 64Zn nuclei.

  2. Achromatic Cooling Channel with Li Lenses

    SciTech Connect

    Balbekov, V.

    2002-04-29

    A linear cooling channel with Li lenses, solenoids, and 201 MHz RF cavities is considered. A special lattice design is used to minimize chromatic aberrations by suppression of several betatron resonances. Transverse emittance of muon beam decreases from 2 mm to 0.5 mm at the channel of about 110 m length. Longitudinal heating is modest, therefore transmission of the channel is rather high: 96% without decay and 90% with decay. Minimal beam emittance achievable by similar channel estimated as about 0.25 mm at surface field of Li lenses 10 T.

  3. The 'LiC Detector Toy' program

    NASA Astrophysics Data System (ADS)

    Regler, M.; Mitaroff, W.; Valentan, M.; Frühwirth, R.; Höfler, R.

    2008-07-01

    LiC is a simple but powerful and flexible software tool, written in MatLab, for basic detector design studies (geometries, material budgets) by determining the resolution of reconstructed track parameters. It is based on a helix track model including multiple scattering, and consists of a simplified simulation of the detector followed by track reconstruction using the Kalman filter. After a short description of LiC's main characteristics, we demonstrate its capabilities by applying this tool in a performance study of the LDC and SiD detector concepts at the International Linear Collider (ILC).

  4. Role of dopants in LiF:Mg,Cu, LiF:Mg,P and LiF:Mg,Cu,P detectors

    SciTech Connect

    Mohammadi, Kh. Moussavi Zarandi, A.; Afarideh, H.; Shahmaleki, S.

    2013-06-15

    In this study, electronic structure of LiF crystal doped with Mg,Cu,P impurities was studied with WIEN2k code on the basis of FPLAPW+lo method. Results show that in Mg-doped LiF composition, an electronic trap was created with impurity concentration of 1.56% and 3.125%. In this condition, the electronic trap with increasing the percentage of the impurities up to 4.687% is annihilated. It was found, that by doping of Mg and Cu or P simultaneously, a hole-trap is created in valence band. It was realized that in LiF:Mg,Cu, LiF:Mg,P and LiF:Mg,Cu,P, Cu impurity and Li atom, have a key role in creation of levels which lead to create electronic and hole traps. Mg impurity and F atom, only have a role in creation of electronic traps. In addition, P impurity has a main role in creation of the electronic and hole traps in LiF:Mg,Cu,P. The activation energy of electronic and hole trap in LiF:Mg,Cu, LiF:Mg,P and LiF:Mg,Cu,P crystalline lattice were obtained as 0.3 and 5.5 eV, 0.92 and 3.4 eV and 0.75 and 3.1 eV, respectively. - Graphical abstract: Figure (a) and (b) shows changes in electronic structure and band gap energy of LiF crystal due to presence of Mg and Cu, Mg and P ions respectively. - Highlights: • Electronic structure of LiF, LiF:Mg,Cu, LiF:Mg,P and LiF:Mg,Cu,P materials were studied with WIEN2K code. • In LiF:Mg,Cu and LiF:Mg,Cu,P, Li atom and Cu impurity have a key role in creation of levels. • F atom and Mg impurity only have a role in creation of electronic traps. • In LiF:Mg,Cu,P, P impurity has a main role in creation of electronic and hole traps.

  5. A novel dual-salts of LiTFSI and LiODFB in LiFePO4-based batteries for suppressing aluminum corrosion and improving cycling stability

    NASA Astrophysics Data System (ADS)

    Li, Faqiang; Gong, Yan; Jia, Guofeng; Wang, Qinglei; Peng, Zhengjun; Fan, Wei; Bai, Bing

    2015-11-01

    The strong corrosion behavior at the Al current collector restricts the application range of lithium bis (trifluoromethanesulfonylimide) (LiTFSI), despite its high stability against water and thermal. SEM, LSV and Tafel curves proved that adding LiODFB into LiTFSI-based electrolytes could suppress aluminum corrosion caused by LiTFSI-based electrolytes. The cycling stability and rate capability of LiFePO4-based batteries using LiTFSI0.6-LiODFB0.4-based electrolytes is excellent as compared to LiFePO4-based batteries using LiPF6-based electrolytes.

  6. Synthesis and characterization of LiZnP and LiZnAs semiconductor material

    NASA Astrophysics Data System (ADS)

    Montag, Benjamin W.; Reichenberger, Michael A.; Arpin, Kevin R.; Sunder, Madhana; Nelson, Kyle A.; Ugorowski, Philip B.; McGregor, Douglas S.

    2015-02-01

    Research for a reliable solid-state semiconductor neutron detector continues because such a device has not been developed, and would have greater efficiency, than present-day gas-filled 3He and 10BF3 neutron detectors. Further, a semiconductor neutron detector would be more compact and rugged than most gas-filled or scintillator neutron detectors. The 6Li(n,t)4He reaction yields a total Q value of 4.78 MeV, a larger yield than the 10B(n,α)7Li, and is easily identified above background radiation interactions. Hence, devices composed of either natural Li (naturally 7.5% 6Li) or enriched 6Li (approximately 95% 6Li) may provide a semiconductor material for compact high-efficiency neutron detectors. A sub-branch of the III-V semiconductors, the filled tetrahedral compounds, known as Nowotny-Juza compounds (AIBIICV), are desirable for their cubic crystal structure and semiconducting electrical properties. These compounds were originally studied for photonic applications. In the present work, Equimolar portions of Li, Zn, and P or As were sealed under vacuum (10-6 Torr) in quartz ampoules with a boron nitride lining, and loaded into a compounding furnace. The ampoule was heated to 200 °C to form the Li-Zn alloy, subsequently heated to 560 °C to form the ternary compound, LiZnP or LiZnAs, and finally annealed to promote crystallization. The chemical composition of the synthesized starting material was confirmed at Galbraith Laboratories, Inc. by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES), which showed the compounds can be reacted in equal ratios, 1-1-1, to form ternary compounds. Recent additions to the procedure have produced higher yields, and greater synthesis reliability. Synthesized powders were also characterized by x-ray diffraction, where lattice constants of 5.751±.001 Å and 5.939±.002 Å for LiZnP and LiZnAs, respectively, were determined.

  7. Comment on "Cycling Li-O₂ batteries via LiOH formation and decomposition".

    PubMed

    Viswanathan, Venkatasubramanian; Pande, Vikram; Abraham, K M; Luntz, Alan C; McCloskey, Bryan D; Addison, Dan

    2016-05-06

    Based on a simple thermodynamic analysis, we show that iodide-mediated electrochemical decomposition of lithium hydroxide (LiOH) likely occurs through a different mechanism than that proposed by Liu et al (Research Article, 30 October 2015, p. 530). The mismatch in thermodynamic potentials for iodide/triiodide (I(-)/I3 (-)) redox and O2 evolution from LiOH implies a different active iodine/oxygen electrochemistry on battery charge. It is therefore possible that the system described in Liu et al may not form the basis for a rechargeable lithium-oxygen (Li-O2) battery. Copyright © 2016, American Association for the Advancement of Science.

  8. Polarization potentials for the 208Pb(7Li,6Li)209Pb transfer

    NASA Astrophysics Data System (ADS)

    Keeley, N.; Rusek, K.

    1997-12-01

    Recent optical model analyses of near-barrier 7Li+208Pb elastic scattering data found a peak in the energy dependence of WOM, the strength of the imaginary part of the optical model potential at the strong absorption radius. It was speculated that this might be due to the polarization potentials produced by couplings to the 208Pb(7Li,6Li)209Pb transfer channels. In this Brief Report we show explicitly that such couplings do indeed produce polarization potentials with the same energy dependence as that observed for the empirical optical potentials.

  9. Some optical properties of KTP, LiIO3, and LiNbO3

    NASA Technical Reports Server (NTRS)

    Gettemy, Donald J.; Harker, William C.; Lindholm, Glenn; Barnes, Norman P.

    1988-01-01

    Measurements of the absorption coefficient for KTP, LiIO3, and LiNbO3 are discussed. The variation of the refractive index with temperature has been measured for KTP and LiIO3. It is necessary to know both the absorption coefficient beta and the variation in the indexes of refraction with temperature change dn/dT to determine the average power limit of a nonlinear interaction. With the dn/dT information, it is also possible to estimate the temperature half width of any nonlinear interaction by calculating the variation of the phase-matching condition with temperature.

  10. Quantifying Li isotope fractionation during smectite formation and implications for the Li cycle

    NASA Astrophysics Data System (ADS)

    Vigier, N.; Decarreau, A.; Millot, R.; Carignan, J.; Petit, S.; France-Lanord, C.

    2008-02-01

    Tri-octahedral Li-Mg smectites (hectorites) were synthesized at temperatures ranging from 25 to 250 °C, in the presence of solutions highly enriched in lithium. After removing all the exchangeable lithium from the synthesized clays, Li isotope fractionation (Δ 7Li clay-solution) was determined. This fractionation was linked to Li incorporation into the structural octahedral site, substituting for Mg 2+. As predicted, experimental Δ 7Li clay-solution inversely correlates with temperature, and ranges from -1.6‰ ± 1.3‰ at 250 °C to -10.0‰ ± 1.3‰ at 90 °C, and then stays relatively constant down to 25 °C. The relatively constant isotope fractionation factor below 90 °C may be due to high concentrations of edge octahedra in low crystallinity smectites. The isotopic fractionation factor ( α), for a given temperature, does not depend on the solution matrix, nor on the amount of structural Li incorporated into the clay. Empirical linear laws for α as a function of 1/ T (K) were inferred. Smectite Li contents and smectite-solution distribution coefficients ( DLi/Mg) increase with temperature, as expected for a substitution process. The fractions of dissolved Li incorporated into the smectite octahedral sites are small and do not depend on the duration of the experiment. In a seawater-like matrix solution, less Li is incorporated into the smectites, probably as a result of competition with dissolved Mg 2+ ions for incorporation into the octahedral sites. The high Li contents observed in marine smectites are therefore best explained either by a significant contribution from basalts, by adsorption processes, or by the influence of seawater chemical composition on distribution coefficients. We also calculate, using present-day estimates of hydrothermal water and river fluxes, that a steady-state ocean would require a relatively large global clay-water Li isotope fractionation (-12‰ to -21‰). This study demonstrates the ability of laboratory experiments to

  11. Li Isotope Studies of Olivine in Mantle Xenoliths by SIMS

    NASA Technical Reports Server (NTRS)

    Bell, D. R.; Hervig, R. L.; Buseck, P. R.

    2005-01-01

    Variations in the ratio of the stable isotopes of Li are a potentially powerful tracer of processes in planetary and nebular environments [1]. Large differences in the 7Li/6Li ratio between the terrestrial upper mantle and various crustal materials make Li isotope composition a potentially powerful tracer of crustal recycling processes on Earth [2]. Recent SIMS studies of terrestrial mantle and Martian meteorite samples report intra-mineral Li isotope zoning [3-5]. Substantial Li isotope heterogeneity also exists within and between the components of chondritic meteorites [6,7]. Experimental studies of Li diffusion suggest the potential for rapid isotope exchange at elevated temperatures [8]. Large variations in 7Li, exceeding the range of unaltered basalts, occur in terrestrial mantle-derived xenoliths from individual localities [9]. The origins of these variations are not fully understood.

  12. Hydrogen storage in LiH: A first principle study

    NASA Astrophysics Data System (ADS)

    Banger, Suman; Nayak, Vikas; Verma, U. P.

    2014-04-01

    First principles calculations have been performed on the Lithium hydride (LiH) using the full potential linearized augmented plane wave (FP-LAPW) method within the framework of density functional theory. We have extended our calculations for LiH+2H and LiH+6H in NaCl structure. The structural stability of three compounds have been studied. It is found that LiH with 6 added Hydrogen atoms is most stable. The obtained results for LiH are in good agreement with reported experimental data. Electronic structures of three compounds are also studied. Out of three the energy band gap in LiH is ˜3.0 eV and LiH+2H and LiH+6H are metallic.

  13. Performance of new 10 kW class MCFC using Li/K and Li/Na electrolyte

    SciTech Connect

    Mugikura, Yoshihiro; Yoshiba, Fumihiko; Izaki, Yoshiyuki; Watanabe, Takao

    1996-12-31

    The molten carbonate fuel cell (MCFC) uses generally mixture of lithium carbonate and potassium carbonate (Li/K) as the electrolyte. NiO cathode dissolution is one of serious problems for MCFC life. The NiO cathode has been found to dissolve into the electrolyte as Ni{sup 2+} ion which is reduced to metallic Ni by H{sub 2} in the fuel gas and bridges the anode and the cathode. The bridges short circuit and degrade cell performance and shorten cell life. Since solubility of NiO in mixture of lithium carbonate and sodium carbonate (Li/Na) is lower than in Li/K, it takes longer time to take place slowing by NiO cathode dissolution in Li/Na compared with in Li/K. The ionic conductivity of Li/Na is higher than of Li/K, however, oxygen solubility in Li/Na is lower 9 than in Li/K. A new 10 kW class MCFC stack composed of Li/K cells and Li/Na cells, was tested. Basic performance of the Li/K cells and Li/Na cells of the stack was reported.

  14. Single step transformation of sulphur to Li2S2/Li2S in Li-S batteries

    NASA Astrophysics Data System (ADS)

    Helen, M.; Reddy, M. Anji; Diemant, Thomas; Golla-Schindler, Ute; Behm, R. Jürgen; Kaiser, Ute; Fichtner, Maximilian

    2015-07-01

    Lithium-sulphur batteries have generated tremendous research interest due to their high theoretical energy density and potential cost-effectiveness. The commercial realization of Li-S batteries is still hampered by reduced cycle life associated with the formation of electrolyte soluble higher-order polysulphide (Li2Sx, x = 4-8) intermediates, leading to capacity fading, self-discharge, and a multistep voltage profile. Herein, we have realized a practical approach towards a direct transformation of sulphur to Li2S2/Li2S in lithium-sulphur batteries by alteration of the reaction pathway. A coconut shell derived ultramicroporous carbon-sulphur composite cathode has been used as reaction directing template for the sulphur. The lithiation/delithiation and capacity fading mechanism of microporous carbon confined sulphur composite was revealed by analyzing the subsurface using X-ray photoelectron spectroscopy. No higher-order polysulphides were detected in the electrolyte, on the surface, and in the subsurface of the cathode composite. The altered reaction pathway is reflected by a single-step profile in the discharge/charge of a lithium-sulphur cell.

  15. Single step transformation of sulphur to Li2S2/Li2S in Li-S batteries

    PubMed Central

    Helen, M.; Reddy, M. Anji; Diemant, Thomas; Golla-Schindler, Ute; Behm, R. Jürgen; Kaiser, Ute; Fichtner, Maximilian

    2015-01-01

    Lithium-sulphur batteries have generated tremendous research interest due to their high theoretical energy density and potential cost-effectiveness. The commercial realization of Li-S batteries is still hampered by reduced cycle life associated with the formation of electrolyte soluble higher-order polysulphide (Li2Sx, x = 4–8) intermediates, leading to capacity fading, self-discharge, and a multistep voltage profile. Herein, we have realized a practical approach towards a direct transformation of sulphur to Li2S2/Li2S in lithium-sulphur batteries by alteration of the reaction pathway. A coconut shell derived ultramicroporous carbon-sulphur composite cathode has been used as reaction directing template for the sulphur. The lithiation/delithiation and capacity fading mechanism of microporous carbon confined sulphur composite was revealed by analyzing the subsurface using X-ray photoelectron spectroscopy. No higher-order polysulphides were detected in the electrolyte, on the surface, and in the subsurface of the cathode composite. The altered reaction pathway is reflected by a single-step profile in the discharge/charge of a lithium-sulphur cell. PMID:26173723

  16. Chemical stability enhancement of lithium conducting solid electrolyte plates using sputtered LiPON thin film

    NASA Technical Reports Server (NTRS)

    West, W. C.; Whitacre, J. F.; Lim, J. R.

    2004-01-01

    Sputter deposition of LiPON films directly onto high Li+ conductivity solid electrolyte plates has been investigated as a means to minimize the reactivity of the plates to metallic Li. The LiPON films were shown to effectively passivate the plates in contact with metallic Li, in contrast to unpassivated plates that reacted immediately in contact with Li metal.

  17. LiDAR utility for natural resource managers

    Treesearch

    Andrew Thomas Hudak; Jeffrey Scott Evans; Alistair Mattthew Stuart. Smith

    2009-01-01

    Applications of LiDAR remote sensing are exploding, while moving from the research to the operational realm. Increasingly, natural resource managers are recognizing the tremendous utility of LiDAR-derived information to make improved decisions. This review provides a cross-section of studies, many recent, that demonstrate the relevance of LiDAR across a suite of...

  18. A new species of the leafhopper genus Multiformis Li & Li (Hemiptera: Cicadellidae: Evacanthinae) from China.

    PubMed

    Li, Yu-Jian; Li, Zi-Zhong

    2014-01-24

    The species of the Oriental leafhopper genus Multiformis Li & Li are reviewed. A new species, Multiformis ramosus sp. nov., from Yunnan Province, China is described and a key to all known species of Multiformis is provided.

  19. Comparative Studies of Optical and Scintillation Properties between LiGaO2 and LiAlO2 Crystals

    NASA Astrophysics Data System (ADS)

    Yanagida, Takayuki; Fujimoto, Yutaka; Koshimizu, Masanori; Kawano, Naoki; Okada, Go; Kawaguchi, Noriaki

    2017-09-01

    We have investigated optical and scintillation properties of LiGaO2 and LiAlO2 crystals. From the transmittance spectra, the absorption edges were found to be around 200 nm but wider band gap was confirmed for LiAlO2 than LiGaO2. Both photoluminescence and scintillation spectra showed a broad emission band peaking at 340 nm in the both crystals. The scintillation decay times of LiGaO2 were 460 ns and 2.8 µs while that of LiAlO2 was 2 µs. Under neutron irradiation from 252Cf, the absolute scintillation light yields of LiGaO2 and LiAlO2 were 3300 ± 300 and 7200 ± 700 ph/n, respectively.

  20. Li-ion diffusion in Li4Ti5O12 and LiTi2O4 battery materials detected by muon spin spectroscopy

    NASA Astrophysics Data System (ADS)

    Sugiyama, Jun; Nozaki, Hiroshi; Umegaki, Izumi; Mukai, Kazuhiko; Miwa, Kazutoshi; Shiraki, Susumu; Hitosugi, Taro; Suter, Andreas; Prokscha, Thomas; Salman, Zaher; Lord, James S.; Mânsson, Martin

    2015-07-01

    Lithium diffusion in spinel Li4Ti5O12 and LiTi2O4 compounds for future battery applications has been studied with muon spin relaxation (μ+SR ) . Measurements were performed on both thin-film and powder samples in the temperature range between 25 and 500 K. For Li4Ti5O12 and above about ˜200 K , the field distribution width (Δ ) is found to decrease gradually, while the field fluctuation rate (ν ) increases exponentially with temperature. For LiTi2O4 , on the contrary, the Δ (T ) curve shows a steplike decrease at ˜350 K , around which the ν (T ) curve exhibits a local maximum. These behaviors suggest that Li+ starts to diffuse above around 200 K for both spinels. Assuming a jump diffusion of Li+ at the tetrahedral 8 a site to the vacant octahedral 16 c site, diffusion coefficients of Li+ at 300 K in the film samples are estimated as (3.2 ±0.8 ) ×10-11 cm2/s for Li4Ti5O12 and (3.6 ±1.1 ) ×10-11 cm2/s for LiTi2O4 . Further, some small differences are found in both thermal activation energies and Li-ion diffusion coefficients between the powder and thin-film samples.

  1. Soft X-Ray Irradiation Effects of Li2O2, Li2CO3 and Li2O Revealed by Absorption Spectroscopy

    PubMed Central

    Qiao, Ruimin; Chuang, Yi-De; Yan, Shishen; Yang, Wanli

    2012-01-01

    Li2O2, Li2CO3, and Li2O are three critical compounds in lithium-air and lithium-ion energy storage systems. Extensive measurements have been carried out to study the chemical species and their evolutions at difference stages of the device operation. While x-ray spectroscopy has been demonstrated to be one of the most powerful tools for such purpose, no systematic study on the irradiation effects have been reported. Here we carry out extensive time, position, and irradiation dependent Li K-edge soft x-ray absorption spectroscopy on these compounds with so far the best energy resolution. The ultra-high resolution in the current study allows the features in the absorption spectra to be well-resolved. The spectral lineshape thus serves as the fingerprints of these compounds, enabling the tracking of their evolution under x-ray irradiation. We found that both Li2O2 and Li2CO3 evidently evolve towards Li2O under the soft x-ray irradiation with Li2CO3 exhibiting a surprisingly higher sensitivity to x-rays than Li2O2. On the other hand, Li2O remains the most stable compound despite experiencing substantial irradiation dose. We thus conclude that high resolution soft x-ray spectroscopy could unambiguously fingerprint different chemical species, but special cautions on irradiation effects would be needed in performing the experiments and interpreting the data properly. PMID:23145116

  2. Raman scattering efficiency in LiTaO3 and LiNbO3 crystals

    NASA Astrophysics Data System (ADS)

    Sanna, S.; Neufeld, S.; Rüsing, M.; Berth, G.; Zrenner, A.; Schmidt, W. G.

    2015-06-01

    LiTaO3 and LiNbO3 crystals are investigated here in a combined experimental and theoretical study that uses Raman spectroscopy in a complete set of scattering geometries and corresponding density-functional theory calculations to provide microscopic information on their vibrational properties. The Raman scattering efficiency is computed from first principles in order to univocally assign the measured Raman peaks to the calculated eigenvectors. Measured and calculated Raman spectra are shown to be in qualitative agreement and confirm the mode assignment by Margueron et al. [J. Appl. Phys. 111, 104105 (2012), 10.1063/1.4716001], thus finally settling a long debate. While the two crystals show rather similar vibrational properties overall, the E-TO9 mode is markedly different in the two oxides. The deviations are explained by a different anion-cation bond type in LiTaO3 and LiNbO3 crystals.

  3. Growth and scintillation properties of Eu doped LiSrI3/LiI eutectics

    NASA Astrophysics Data System (ADS)

    Kamada, Kei; Chiba, Hiroyuki; Yoshino, Masao; Yamaji, Akihiro; Shoji, Yasuhiro; Kurosawa, Shunsuke; Yokota, Yuui; Ohashi, Yuji; Yoshikawa, Akira

    2017-06-01

    Eu doped LiSrI3/LiI eutectics were grown by the Bridgman method in a quartz ample with 4 mm inner diameter. and their directionally solidified eutectic system has been investigated. Growth rate was 0.3 mm/min. The eutectic showed well aligned eutectic structure and optically transparent. Grown Eu doped LiSrI3/LiI eutectic shows 400 nm emission ascribed to Eu2+ 4f-5d transition under X-ray excitation. The light yield was around 26,000 photon/MeV for 662 keV gamma-ray and 35,000 photons for 5.5 MeV alpha-ray.

  4. Enabling High Energy Density Li-Ion Batteries through Li{sub 2}O Activation.

    SciTech Connect

    Abouimrane, Ali; Cui, Yanjie; Chen, Zonghai; Belharouak, Ilias; Yahia, Hamdi B.; Wu, Huiming; Assary, Rajeev; Curtiss, Larry A.; Amine, Khalil

    2016-09-01

    Lithium oxide (Li2O) is activated in the presence of a layered composite cathode material (HEM) significantly increasing the energy density of lithium-ion batteries. The degree of activation depends on the current rate, electrolyte salt, and anode type. In full-cell tests, the Li2O was used as a lithium source to counter the first-cycle irreversibility of high-capacity composite alloy anodes. When Li2O is mixed with HEM to serve as a cathode, the electrochemical performance was improved in a full cell having an SiO-SnCoC composite as an anode. The mechanism behind the Li2O activation could also explain the first charge plateau and the abnormal high capacity associated with these high energy cathode materials.

  5. Distorted-wave Born approximation study of the 11Li(p,t)9Li reaction

    NASA Astrophysics Data System (ADS)

    Cowley, A. A.

    2016-06-01

    The reaction 11Li(p,t)9Li(gs) at an incident energy of 4 MeV is treated in terms of a simplistic distorted-wave Born approximation transfer. The halo neutrons involved in the reaction are treated as a di-neutron cluster transferred in a simultaneous process. This appears to be a good approximation of the mechanism. The dominant contribution to the reaction comes from the known (1s 1/2)2 structure component of the ground state of 11Li, and the cross section angular distribution seems to be relatively insensitive to the fact that 11 Li has an anomalously large radius due to its Borromean halo properties. Significantly this simple treatment of the reaction is in much better agreement with the experimental angular distribution than a more sophisticated calculation.

  6. LiF/CaF2/LiBaF3 ternary fluoride eutectic scintillator

    NASA Astrophysics Data System (ADS)

    Hishinuma, Kosuke; Kamada, Kei; Kurosawa, Shunsuke; Yamaji, Akihiro; Pejchal, Jan; Yokota, Yuui; Ohashi, Yuji; Yoshikawa, Akira

    2015-04-01

    LiF/CaF2/LiBaF3 ternary eutectic scintillators were grown by the µ-PD method. In the solidified eutectic the phases were uniformly distributed in the transverse direction and aligned along the growth direction. For the Eu-doped samples, the expected emission peak observed at 425 nm was ascribed to Eu2+ 5d-4f transition from Eu:CaF2 under X-ray excitation. The LiF/CaF2/LiBaF3 ternary eutectic scintillators showed a light yield around 7,000 photons/neutron and decay time of 260 ns (73.6%) and 50 ns (26.4%).

  7. Probing the failure mechanism of nanoscale LiFePO₄ for Li-ion batteries

    SciTech Connect

    Gu, Meng; Shi, Wei; Zheng, Jianming; Yan, Pengfei; Zhang, Ji-guang; Wang, Chongmin

    2015-05-18

    LiFePO4 is a high power rate cathode material for lithium ion battery and shows remarkable capacity retention, featuring a 91% capacity retention after 3300 cycles. In this work, we use high-resolution transmission electron microscopy (HRTEM), energy dispersive x-ray spectroscopy (EDS), and electron energy loss spectroscopy (EELS) to study the gradual capacity fading mechanism of LiFePO4 materials. We found that upon prolonged electrochemical cycling of the battery, the LiFePO4 cathode shows surface amorphization and loss of oxygen species, which directly contribute to the gradual capacity fading of the battery. The finding is of great importance for the design and improvement of new LiFePO4 cathode for high-energy and high-power rechargeable battery for electric transportation.

  8. Electrochemical formation of Mg-Li-Ca alloys by codeposition of Mg, Li and Ca from LiCl-KCl-MgCl2-CaCl2 melts.

    PubMed

    Yan, Yong De; Zhang, Mi Lin; Xue, Yun; Han, Wei; Cao, Dian Xue; Jing, Xiao Yan; He, Li Yi; Yuan, Yi

    2009-08-07

    This work presents electrochemical formation of Mg-Li-Ca alloys via codeposition of Mg, Li and Ca on a molybdenum electrode in KCl-LiCl-MgCl(2)-CaCl(2) melts at 943 K. Cyclic voltammograms (CVs) showed that the underpotential deposition (UPD) of calcium on pre-deposited magnesium leads to the formation of a liquid Mg-Ca alloy, and the succeeding underpotential deposition of lithium on pre-deposited Mg-Ca alloy leads to the formation of a liquid Mg-Li-Ca solution. Chronopotentiometric measurements indicated that the codepositon of Mg, Li and Ca occurs at current densities more negative than -0.31 A cm(-2) in LiCl-KCl-MgCl(2) (5 wt%) melts containing 1 wt% CaCl(2). Chronoamperograms demonstrated that the onset potential for the codeposition of Mg, Li and Ca is -2.200 V, and the codeposition of Mg, Li and Ca is formed when the applied potentials are more negative than -2.200 V. X-Ray diffraction (XRD) indicated that Mg-Li-Ca alloys with different phases were formed via galvanostatic electrolysis. The microstructures of typical alpha and beta phases of Mg-Li-Ca alloys were characterized by optical microscope (OM) and scanning electron microscopy (SEM). The analysis of energy dispersive spectrometry (EDS) showed that the element Ca mainly distributes along grain boundary in Mg-Li-Ca alloys. The results of inductively coupled plasma analysis determined that the chemical compositions of Mg-Li-Ca alloys correspond with the phase structures of XRD patterns, and the lithium and calcium contents of Mg-Li-Ca alloys depend on the concentrations of MgCl(2) and CaCl(2).

  9. Genetics Home Reference: Li-Fraumeni syndrome

    MedlinePlus

    ... Sarcoma family syndrome of Li and Fraumeni Sarcoma, breast, leukemia, and adrenal gland (SBLA) syndrome SBLA syndrome Related Information How are genetic conditions and genes named? Additional Information & ... Topic: Bone Cancer Health Topic: Breast Cancer Health Topic: Cancer Health Topic: Soft Tissue ...

  10. LiYbCl4(THF)4

    PubMed Central

    Richtera, Lukas; Jancik, Vojtech; Hermanova, Sona; Krpoun, Karel; Thompson-Montero, Kimberly

    2011-01-01

    The title compound, di-μ-chlorido-dichlorido-1κ2 Cl-tetra­kis­(tetra­hydro­furan)-1κ2 O,2κ2 O-lithiumytterbium(III), [LiYbCl4(C4H8O)4], was prepared by the reaction of YbCl3(THF)3 with LiCl in THF (THF is tetra­hydro­furan). The central motif of the structure is a Yb(μ-Cl)2Li ring. The Yb atom is hexa­coordinated to four Cl atoms and two THF mol­ecules oriented in a trans fashion. The Li atom has a tetra­hedral environment and is coordinated to two Cl atoms and two THF mol­ecules. No inter­molecular inter­actions other than van der Waals forces were observed. Two of the THF mol­ecules are disordered over two positions. PMID:21754604

  11. 6Li foil thermal neutron detector

    SciTech Connect

    Ianakiev, Kiril D; Swinhoe, Martyn T; Favalli, Andrea; Chung, Kiwhan; Macarthur, Duncan W

    2010-01-01

    In this paper we report on the design of a multilayer thermal neutron detector based on {sup 6}Li reactive foil and thin film plastic scintillators. The {sup 6}Li foils have about twice the intrinsic efficiency of {sup 10}B films and about four times higher light output due to a unique combination of high energy of reaction particles, low self absorption, and low ionization density of tritons. The design configuration provides for double sided readout of the lithium foil resulting in a doubling of the efficiency relative to a classical reactive film detector and generating a pulse height distribution with a valley between neutron and gamma signals similar to {sup 3}He tubes. The tens of microns thickness of plastic scintillator limits the energy deposited by gamma rays, which provides the necessary neutron/gamma discrimination. We used MCNPX to model a multilayer Li foil detector design and compared it with the standard HLNCC-II (18 {sup 3}He tubes operated at 4 atm). The preliminary results of the {sup 6}Li configuration show higher efficiency and one third of the die-away time. These properties, combined with the very short dead time of the plastic scintillator, offer the potential of a very high performance detector.

  12. Synthesis of Li excess LiFePO4/C using iron chloride extracted from steel scrap pickling

    NASA Astrophysics Data System (ADS)

    Yoon, Man-Soon; Islam, Mobinul; Park, Young Min; Hoon, Song Jung; Son, Jong-Tae; Ur, Soon-Chul

    2014-07-01

    Olivine-type Li rich Li1+xFePO4/C composites are synthesized by a solid state reaction process using premilled Li2CO3 and pre-synthesized amorphous FePO4· xH2O powders. The amorphous FePO4· xH2O powders are prepared from an industrial waste liquid (by-product), a FeCl3 (38%) solution, via a precipitation process. In addition, lithium carbonate is pre-milled using a high energy nano mill to control particle sizes and shape differences for enhancing the reaction activity in the starting materials. The main purpose of this study is to investigate the effect of excess Li on the electrochemical properties of LiFePO4 cathode materials. The pre-synthesized FePO4 powders are mixed with pre-milled lithium carbonate and glucose (8 wt%) using a ball-mill process. The structural characteristics of the Li1+xFePO4/C composites are examined by XRD and SEM. To investigate the effect of excess Li content on the electrochemical properties in Li1+xFePO4/C composites, a Li[LiPF6 (Ethylene carbonate + Dimethyl carbonate)] Li1+xFePO4/C model cell is used. It is demonstrated that the 1% Li rich Li/[Li1.01FePO4/C] cell exhibits the best electrochemical performance and delivers an initial discharge capacity of 161 mAhg-1, which is 25 mAhg-1 higher than that of the Li/[LiFePO4/C] cell.

  13. On the reduction of generalized polylogarithms to Li n and Li2 ,2 and on the evaluation thereof

    NASA Astrophysics Data System (ADS)

    Frellesvig, Hjalte; Tommasini, Damiano; Wever, Christopher

    2016-03-01

    We give expressions for all generalized polylogarithms up to weight four in terms of the functions log, Li n , and Li2,2, valid for arbitrary complex variables. Furthermore we provide algorithms for manipulation and numerical evaluation of Li n and Li2,2, and add codes in Mathematica and C++ implementing the results. With these results we calculate a number of previously unknown integrals, which we add in appendix C.

  14. Pt and Pd catalyzed oxidation of Li2O2 and DMSO during Li-O2 battery charging.

    PubMed

    Gittleson, Forrest S; Ryu, Won-Hee; Schwab, Mark; Tong, Xiao; Taylor, André D

    2016-05-05

    Rechargeable Li-O2 and Li-air batteries require electrode and electrolyte materials that synergistically promote long-term cell operation. In this study, we investigate the role of noble metals Pt and Pd as catalysts in the Li-O2 oxidation process and their compatibility with dimethyl sulfoxide (DMSO) based electrolytes. We identify a basis for low potential Li2O2 evolution followed by oxidative decomposition of the electrolyte to form carbonate side products.

  15. Lithium concentration and Li isotopic compositions of carbonatitic complexes

    NASA Astrophysics Data System (ADS)

    Halama, R.; McDonough, W. F.; Rudnick, R. L.; Ash, R. D.; Keller, J.; Klaudius, J.; Trumbull, R.

    2005-12-01

    To evaluate the Li isotopic signatures of the mantle sources of carbonatites and the influence of magmatic differentiation and post-magmatic processes on δ7Li, we determined the Li concentrations and isotopic compositions of carbonatites and spatially associated silicate rocks, spanning a wide range in composition and age. Natrocarbonatites from Oldoinyo Lengai (1995 and 2000 eruptions) have high Li concentrations (211-292 ppm) and uniform Li isotopic signatures (δ7Li = +4.4 to +5.1 per mil). Associated silicate rocks (melilitite, nephelinite and phonolite) have lower Li concentrations (16-47 ppm) and trend towards lighter Li isotopic values (δ7Li = 0 to +3.5 per mil). Clinopyroxenes from these lavas are significantly lighter than the whole rocks by 1 to 6 per mil. Since the lavas appear to be fresh, this suggests fractionation of Li isotopes between minerals and whole rocks. In comparison to the modern natrocarbonatites, Proterozoic calciocarbonatites from Greenland (Grønnedal-Ika) and Cretaceous calciocarbonatites from Namibia (Kalkfeld) are poor in Li (< 2 ppm) and have more scattered Li isotopic compositions (δ7Li = -1 to +4 and -0.5 to +5 per mil, respectively). The lower δ7Li values may reflect contamination by crustal Li, since the low Li contents in the carbonatites make them susceptible to this. Silicate lavas from Kalkfeld have higher Li concentrations (11-12 ppm) than their associated carbonatites, but overlapping isotopic compositions (δ7Li = +4 to +6 per mil). At Grønnedal-Ika, clinopyroxene separates from nepheline syenites vary considerably in δ7Li from -6 to +5. Since Li is preferentially partitioned into fenitizing fluids [1] and an enrichment of light 6Li in fluids during degassing can be anticipated [2], the trend towards negative δ7Li can be interpreted as a result of variable interaction with metasomatizing fluids. However, fractionation of Li isotopes between minerals and melts may also have played a role. Our preliminary data

  16. Phase relationships in positive electrodes of high temperature Li-Al/LiCl-KCl/FeS2 cells

    NASA Astrophysics Data System (ADS)

    Tomczuk, Z.; Tani, B.; Otto, N. C.; Roche, M. F.; Vissers, D. R.

    1982-05-01

    The phases present in FeS2 electrodes operated in LiCl-KCl eutectic electrolyte are determined by X-ray diffraction and metallographic examination. The phases are FeS2, KFeS2, Li3Fe2S4, Li2.33Fe0.67S2, Fe/1-x/S, Li2FeS2, LiK6Fe24S26Cl, Li2S, and Fe. The metallographic and crystallographic characteristics of these phases are given. The sequence of Li-Fe-S phases in the FeS2 electrode is found to be in accord with the sequence predicted from the equilibrium LiFe-S phase diagram. It is noted that two of the Li-Fe-S phases found at room temperature (Li2.33Fe0.67S2 and Li2FeS2) result from decomposition on cooling of a solid solution phase: Li/2+x/Fe/1-x/S2, x ranging from 0 to 0.33.

  17. Li diffusion and substitution in chemically diverse synthetic zircon

    NASA Astrophysics Data System (ADS)

    Trail, D.

    2015-12-01

    Li concentrations and 7Li/6Li ratios in zircon may potentially trace crustal recycling because continental and mantle-derived zircons yield distinct values (Ushikubo et al. 2008; Bouvier et al. 2012). To some extent, the usefulness of these differences may depend upon the retentively of Li in zircon. Cherniak and Watson (2010) measured relatively high diffusivities for Li; here we sought to discover the scenarios under which Li mobility might be inhibited by charge compensating cations. We conducted "in" diffusion experiments in synthetic Lu-doped (~5000 ppm), P-doped (~250 ppm), and nearly pure zircon following the procedure in Cherniak and Watson (2010). In separate experiments, Li was ion implanted at depth within polished Mud Tank zircon slabs to form a Gaussian Li concentration profile; the relaxed concentration profile was measured after heating the zircon slabs. In all experiments, which ranged from 920 to 650 oC, calculated diffusivities were in agreement with a previously established Arrhenius relationship calibrated on trace element poor Mud Tank zircon (Cherniak and Watson, 2010). We also conducted complementary LA-ICP-MS mapping on the surfaces of P- and Lu-doped synthetic zircon crystals after the Li diffusion results were obtained. This revealed heterogeneous though patterned correlation between Li+Lu in the near surface of the crystal (no strong patterns emerged for P+Li). And finally, we observed that synthetic sector-zoned zircon exhibits near step function Li concentration profiles - correlating with changes in the rare earth element concentrations across these sectors - which allowed us to examine Li diffusion in yet another manner. Re-heating these grains followed by LA-ICP-MS analysis revealed significant Li migration, with no detectable migration of the rare earth elements. While our experiments cannot be considered exhaustive, we have yet to find a scenario where Li mobility in synthetic zircon depends on charge compensating cations.

  18. Capturing and Processing Soil GHG Fluxes Using the LI-COR LI-8100A

    NASA Astrophysics Data System (ADS)

    Xu, Liukang; McDermitt, Dayle; Hupp, Jason; Johnson, Mark; Madsen, Rod

    2015-04-01

    The LI-COR LI-8100A Automated Soil CO2 Flux System is designed to measure soil CO2 efflux using automated chambers and a non-steady state measurement protocol. While CO2 is an important gas in many contexts, it is not the only gas of interest for many research applications. With some simple plumbing modifications, many third party analyzers capable of measuring other trace gases, e.g. N2O, CH4, or 13CO2 etc., can be interfaced with the LI-8100A System, and LI-COR's data processing software (SoilFluxPro™) can be used to compute fluxes for these additional gases. In this paper we describe considerations for selecting an appropriate third party analyzer to interface with the system, how to integrate data into the system, and the procedure used to compute fluxes of additional gases in SoilFluxPro™. A case study is presented to demonstrate methane flux measurements using an Ultra-Portable Greenhouse Gas Analyzer (Ultra-Portable GGA, model 915-0011), manufactured by Los Gatos Research and integrated into the LI-8100A System. Laboratory and field test results show that the soil CO2 efflux based on the time series of CO2 data measured either with the LI-8100A System or with the Ultra-Portable GGA are essentially the same. This suggests that soil GHG fluxes measured with both systems are reliable.

  19. Correlation of anisotropy and directional conduction in β-Li3PS4 fast Li+ conductor

    DOE PAGES

    Chen, Yan; Cai, Lu; Liu, Zengcai; ...

    2015-07-06

    Our letter reports the correlation of anisotropy and directional conduction in the fast Li+ conductor β-Li3PS4, one of the low-symmetry crystalline electrolyte candidates. The material has both high conductivity and good stability that serves well for the large-scale energy storage applications of all-solid-state lithium ion batteries. The anisotropic physical properties, demonstrated here by the thermal expansion coefficients, are crucial for compatibility in the solid-state system and battery performance. Neutron and X-ray powder diffraction measurements were done to determine the crystal structure and thermal stability. Moreover, the crystallographic b-axis was revealed as a fast expansion direction, while negligible thermal expansion wasmore » observed along the a-axis around the battery operating temperatures. The anisotropic behavior has its structural origin from the Li+ conduction channels with incomplete Li occupancy and a flexible connection of LiS4 and PS4 tetrahedra within the framework. This indicates a strong correlation in the direction of the ionic transport in the low-symmetry Li+ conductor.« less

  20. In-house fabrication and testing capabilities for Li and Li-ion 18650 cells

    NASA Astrophysics Data System (ADS)

    Nagasubramanian, G.

    2010-04-01

    For over 10 years Sandia Labs have been involved in an US DOE-funded program aimed at developing electric vehicle batteries for transportation applications. Currently this program is called "Advanced Battery Research (ABR)." In this effort we were preparing 18650 cells with electrodes supplied by or purchased from private companies for thermal abuse and electrical characterization studies. Lately, we are coating our own electrodes, building cells and evaluating performance. This paper describes our extensive in-house facilities for slurry making, electrode coating, cell winding etc. In addition, facilities for electrical testing and thermal abuse will be described. This facility allows us to readjust our focus quickly to the changing demands of the still evolving ABR program. Additionally, we continue to make cells for our internal use. We made several 18650 cells both primary (Li-CFx) and secondary (Li-ion) and evaluated performance. For example Li-CFx cells gave ~2.9Ahr capacity at room temperature. Our high voltage Li-ion cells consisting of carbon anode and cathode based on LiNi 0.4Mn 0.3Co 0.3O2 in organic electrolytes exhibited reproducible behavior and gave capacity on the order of 1Ahr. Performance of Li-ion cells at different temperatures and thermal abuse characteristics will be presented.

  1. Epitaxial thin film growth of LiH using a liquid-Li atomic template

    SciTech Connect

    Oguchi, Hiroyuki; Ikeshoji, Tamio; Orimo, Shin-ichi; Ohsawa, Takeo; Shiraki, Susumu; Hitosugi, Taro; Kuwano, Hiroki

    2014-11-24

    We report on the synthesis of lithium hydride (LiH) epitaxial thin films through the hydrogenation of a Li melt, forming abrupt LiH/MgO interface. Experimental and first-principles molecular dynamics studies reveal a comprehensive microscopic picture of the crystallization processes, which sheds light on the fundamental atomistic growth processes that have remained unknown in the vapor-liquid-solid method. We found that the periodic structure that formed, because of the liquid-Li atoms at the film/MgO-substrate interface, serves as an atomic template for the epitaxial growth of LiH crystals. In contrast, films grown on the Al{sub 2}O{sub 3} substrates indicated polycrystalline films with a LiAlO{sub 2} secondary phase. These results and the proposed growth process provide insights into the preparation of other alkaline metal hydride thin films on oxides. Further, our investigations open the way to explore fundamental physics and chemistry of metal hydrides including possible phenomena that emerge at the heterointerfaces of metal hydrides.

  2. Making Li-air batteries rechargeable: material challenges

    SciTech Connect

    Shao, Yuyan; Ding, Fei; Xiao, Jie; Zhang, Jian; Xu, Wu; Park, Seh Kyu; Zhang, Jiguang; Wang, Yong; Liu, Jun

    2013-02-25

    A Li-air battery could potentially provide three to five times higher energy density/specific energy than conventional batteries, thus enable the driving range of an electric vehicle comparable to a gasoline vehicle. However, making Li-air batteries rechargeable presents significant challenges, mostly related with materials. Herein, we discuss the key factors that influence the rechargeability of Li-air batteries with a focus on nonaqueous system. The status and materials challenges for nonaqueous rechargeable Li-air batteries are reviewed. These include electrolytes, cathode (electocatalysts), lithium metal anodes, and oxygen-selective membranes (oxygen supply from air). The perspective of rechargeable Li-air batteries is provided.

  3. A New Insight into the Polaron-Li Complex Diffusion in Cathode Material LiFe1-yMnyPO4 for Li Ion Batteries

    NASA Astrophysics Data System (ADS)

    Dinh, Van An; Nara, Jun; Ohno, Takahisa

    2012-04-01

    Based on the Heyd-Scuseria-Ernzerhof hybrid density functionals study, we proposed a new insight into the diffusion of polaron-Li vacancy complexes in LiFe1-yMnyPO4 (y=0,1/2,1). It is found that the polaron migrates along a crossing or a parallel path relative to the Li moving direction. In LiFePO4, the complex diffusion along the zigzag pathway is favorable and has a barrier of 600 meV, while the diffusion along the parallel pathway with a barrier of 623 meV is favorable in LiMnPO4. For LiFe1/2Mn1/2PO4, since the polaron is formed within a single Fe layer, the diffusion proceeds along the parallel pathway with a barrier of 635 meV.

  4. Electronic structures of filled tetrahedral semiconductors LiMgN and LiZnN: conduction band distortion

    NASA Astrophysics Data System (ADS)

    Yu, L. H.; Yao, K. L.; Liu, Z. L.

    2004-12-01

    The band structures of the filled tetrahedral semiconductors LiMgN and LiZnN, viewed as the zinc-blende (MgN) - and (ZnN) - lattices partially filled with He-like Li + ion interstitials, were studied using the full-potential linearized augmented plane wave method (FP-LAPW) within density functional theory. The conduction band distortions of LiMgN and LiZnN, compared to their “parent” zinc-blende analog AlN and GaN, are discussed. It was found that the insertion of Li + ions at the interstitial sites near the cation or anion pushes the conduction band minimum of the X point in the Brillouin zone upward, relative to that of the Γ point, for both (MgN) - and (ZnN) - lattices (the valence band maximum is at Γ for AlN, GaN, LiMgN, and LiZnN), which provides a method to convert a zinc-blende indirect gap semiconductor into a direct gap material, but the conduction band distortion of the β phase (Li + near the cation) is quite stronger than that of the α phase (Li + near the anion). The total energy calculations show the α phase to be more stable than the β phase for both LiMgN and LiZnN. The Li-N and Mg-N bonds exhibit a strong ionic character, whereas the Zn-N bond has a strong covalent character in LiMgN and LiZnN.

  5. Concentration dependence of Li+/Na+ diffusion in manganese hexacyanoferrates

    NASA Astrophysics Data System (ADS)

    Takachi, Masamitsu; Fukuzumi, Yuya; Moritomo, Yutaka

    2016-06-01

    Manganese hexacyanoferrates (Mn-HCFs) with a jungle-gym-type structure are promising cathode materials for Li+/Na+ secondary batteries (LIBs/SIBs). Here, we investigated the diffusion constants D Li/D Na of Li+/Na+ against the Li+/Na+ concentration x Na/x Li and temperature (T) of A 1.32Mn[Fe(CN)6]0.833.6H2O (A = Li and Na). We evaluated the activation energy E\\text{a}\\text{Li}/E\\text{a}\\text{Na} of D Li/D Na against x Na/x Li. We found that E\\text{a}\\text{Na} steeply increases with x Na from 0.41 eV at x Na = 0.69 to 0.7 eV at 1.1. The increase in E\\text{a}\\text{Na} is ascribed to the occupancy effect of the Na+ site. The increase in E\\text{a}\\text{Li} is suppressed, probably because the number of Li+ sites is three times that of Na+ sites.

  6. Amorphous Li2 O2 : Chemical Synthesis and Electrochemical Properties.

    PubMed

    Zhang, Yelong; Cui, Qinghua; Zhang, Xinmin; McKee, William C; Xu, Ye; Ling, Shigang; Li, Hong; Zhong, Guiming; Yang, Yong; Peng, Zhangquan

    2016-08-26

    When aprotic Li-O2 batteries discharge, the product phase formed in the cathode often contains two different morphologies, that is, crystalline and amorphous Li2 O2 . The morphology of Li2 O2 impacts strongly on the electrochemical performance of Li-O2 cells in terms of energy efficiency and rate capability. Crystalline Li2 O2 is readily available and its properties have been studied in depth for Li-O2 batteries. However, little is known about the amorphous Li2 O2 because of its rarity in high purity. Herein, amorphous Li2 O2 has been synthesized by a rapid reaction of tetramethylammonium superoxide and LiClO4 in solution, and its amorphous nature has been confirmed by a range of techniques. Compared with its crystalline siblings, amorphous Li2 O2 demonstrates enhanced charge-transport properties and increased electro-oxidation kinetics, manifesting itself a desirable discharge phase for high-performance Li-O2 batteries. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Revision of the Li13Si4 structure

    PubMed Central

    Zeilinger, Michael; Fässler, Thomas F.

    2013-01-01

    Besides Li17Si4, Li16.42Si4, and Li15Si4, another lithium-rich representative in the Li–Si system is the phase Li13Si4 (trideca­lithium tetra­silicide), the structure of which has been determined previously [Frank et al. (1975 ▶). Z. Naturforsch. Teil B, 30, 10–13]. A careful analysis of X-ray diffraction patterns of Li13Si4 revealed discrepancies between experimentally observed and calculated Bragg positions. Therefore, we redetermined the structure of Li13Si4 on the basis of single-crystal X-ray diffraction data. Compared to the previous structure report, decisive differences are (i) the introduction of a split position for one Li site [occupancy ratio 0.838 (7):0.162 (7)], (ii) the anisotropic refinement of atomic displacement parameters for all atoms, and (iii) a high accuracy of atom positions and unit-cell parameters. The asymmetric unit of Li13Si4 contains two Si and seven Li atoms. Except for one Li atom situated on a site with symmetry 2/m, all other atoms are on mirror planes. The structure consists of isolated Si atoms as well as Si–Si dumbbells surrounded by Li atoms. Each Si atom is either 12- or 13-coordinated. The isolated Si atoms are situated in the ab plane at z = 0 and are strictly separated from the Si–Si dumbbells at z = 0.5. PMID:24454148

  8. Synthesis and optical characterization of LiKB4O7, Li2B6O10, and LiCsB6O10 glasses

    SciTech Connect

    Adamiv, V.; Teslyuk, I.; Dyachok, Ya.; Romanyuk, G.; Krupych, O.; Mys, O.; Martynyuk-Lototska, I.; Burak, Ya.; Vlokh, R.

    2010-10-01

    In the current work we report on the synthesis of LiKB4O7, Li2B6O10, and LiCsB6O10 borate glasses. The results for their piezo-optic, acousto-optic, acoustic, elastic, refractive, optical transmission, and optical resistance properties are also presented. It is shown that some of these glasses represent efficient acousto-optic materials that are transparent down to the vacuum ultraviolet range and highly resistant to laser radiation.

  9. Synthesis and optical characterization of LiKB4O7, Li2B6O10, and LiCsB6O10 glasses.

    PubMed

    Adamiv, V; Teslyuk, I; Dyachok, Ya; Romanyuk, G; Krupych, O; Mys, O; Martynyuk-Lototska, I; Burak, Ya; Vlokh, R

    2010-10-01

    In the current work we report on the synthesis of LiKB(4)O(7), Li(2)B(6)O(10), and LiCsB(6)O(10) borate glasses. The results for their piezo-optic, acousto-optic, acoustic, elastic, refractive, optical transmission, and optical resistance properties are also presented. It is shown that some of these glasses represent efficient acousto-optic materials that are transparent down to the vacuum ultraviolet range and highly resistant to laser radiation.

  10. Ab-initio studies on Li doping, Li-pairs, and complexes between Li and intrinsic defects in ZnO

    NASA Astrophysics Data System (ADS)

    Vidya, R.; Ravindran, P.; Fjellvâg, H.

    2012-06-01

    First-principles density functional calculations have been performed on Li-doped ZnO using all-electron projector augmented plane wave method. Li was considered at six different interstitial sites (Lii), including anti-bonding and bond-center sites and also in substitutional sites such as at Zn-site (Lizn) and at oxygen site (Lio) in the ZnO matrix. Stability of LiZn over Lii is shown to depend on synthetic condition, viz., LiZn is found to be more stable than Lii under O-rich conditions. Hybrid density functional calculations performed on LiZn indicate that it is a deep acceptor with (0/-) transition taking place at 0.74 eV above valence band maximum. The local vibrational frequencies for Li-dopants are calculated and compared with reported values. In addition, we considered the formation of Li-pair complexes and their role on electronic properties of ZnO. Present study suggests that at extreme oxygen-rich synthesis condition, a pair of acceptor type LiZn-complex is found to be stable over the compensating Lii + LiZn pair. The stability of complexes formed between Li impurities and various intrinsic defects is also investigated and their role on electronic properties of ZnO has been analyzed. We have shown that a complex between LiZn and oxygen vacancy has less formation energy and donor-type character and could compensate the holes generated by Li-doping in ZnO.

  11. Exploring Half Metals in Li-based Half Heusler Alloys

    NASA Astrophysics Data System (ADS)

    Busemeyer, B.; Shaughnessy, M.; Fong, C. Y.

    2011-11-01

    We examine the electronic and magnetic properties of three Li-related half Heusler alloys, namely LiMnN, LiMnP, and LiMnSi in a structure close to the well-known zinc-blende structure in the attempt to search for new half metallic materials. If they do demonstrate half metallic properties, this will open new grounds for finding half metallic spintronic materials. Our results will furnish guidelines for future exploration of alkali-related half metals. Using the primitive cell LiMnSi is a half metal, while the pnictides are not. However when the conventional cell is used, we find that Li3Mn4P4 and Li3Mn4N4 are half metals. The physical reason for these two pnictides to be half metallic and for their magnetic moment per unit cell will be presented.

  12. Nanoscale coating of LiMO2 (M = Ni, Co, Mn) nanobelts with Li+-conductive Li2TiO3: toward better rate capabilities for Li-ion batteries.

    PubMed

    Lu, Jun; Peng, Qing; Wang, Weiyang; Nan, Caiyun; Li, Lihong; Li, Yadong

    2013-02-06

    By using a novel coating approach based on the reaction between MC(2)O(4)·xH(2)O and Ti(OC(4)H(9))(4), a series of nanoscale Li(2)TiO(3)-coated LiMO(2) nanobelts with varied Ni, Co, and Mn contents was prepared for the first time. The complete, thin Li(2)TiO(3) coating layer strongly adheres to the host material and has a 3D diffusion path for Li(+) ions. It is doped with Ni(2+) and Co(3+) ions in addition to Ti(4+) in LiMO(2), both of which were found to favor Li(+)-ion transfer at the interface. As a result, the coated nanobelts show improved rate, cycling, and thermal capabilities when used as the cathode for Li-ion battery.

  13. Investigation of structural, mechanical, electronic, optical, and dynamical properties of cubic BaLiF3, BaLiH3, and SrLiH3

    NASA Astrophysics Data System (ADS)

    Yalcin, Battal G.; Salmankurt, Bahadır; Duman, Sıtkı

    2016-03-01

    The structural, mechanical, electronic, optical, and dynamical properties of BaLiF3, BaLiH3, and SrLiH3 cubic perovskite materials are theoretically investigated by using first principles calculations. Obtained results are in reasonable agreement with other available theoretical and experimental studies. The considered materials are found to be mechanically stable in the cubic structure. We found that all materials are brittle. The modified Becke-Johnson (mBJ) exchange potential has been used here to obtain an accurate band order. The calculated band-gap energy value of BaLiF3 (8.26 eV) within the mBJ potential agrees very well with the experimentally reported value of 8.41 eV. In order to have a deeper understanding of the bonding mechanism and the effect of atomic relaxation on the electronic band structure, the total and partial density of states have also been calculated. We have investigated the fundamental optical properties, such as the real ɛ 1(ω) and imaginary ɛ 2(ω) parts of the dielectric function, absorption coefficient α(ω), reflectivity R(ω), and refractive index n(ω) in the energy range from 0 to 40 eV within the mBJ potential. The band-gap energy obtained from the absorption spectrum is around 8.76, 3.99, and 3.31 eV for BaLiF3, BaLiH3, and SrLiH3 crystals, respectively. It should be noted that BaLiF3 could be a strong potential candidate as a laser material for the development of a vacuum-ultraviolet light emitting diode once direct transition is confirmed by experimental studies. Finally, we have calculated the lattice dynamical properties of BaLiF3, BaLiH3, SrLiH3, and SrLiF3 crystals. The full phonon dispersion curves of these materials are reported for the first time. Our results clearly indicate that the materials are dynamically stable, except for SrLiF3, in the cubic structure. The obtained zone-center phonon frequencies of BaLiF3, BaLiH3, and SrLiH3 accord very well with previous experimental measurements.

  14. Motion of Li(+) in nanoengineered LiBH(4) and LiBH(4):Al(2)O(3) comparison with the microcrystalline form.

    PubMed

    Epp, Viktor; Wilkening, Martin

    2013-11-11

    The introduction of structural disorder and large volume fractions of different kinds of interfaces enables the manipulation of ion dynamics in solids. Variable-temperature solid-state NMR relaxometry is highly useful to study Li(+) jump processes. If carried out as a function of frequency, the resulting NMR relaxation rates also contain information on the dimensionality (1D, 2D, or 3D) of the diffusion process. Recently, NMR relaxometry has revealed the 2D nature of Li hopping in LiBH4 , and thus this hydride is an interesting ion conductor for further diffusion studies on the spatially confined motion of Li spins. Here, nanocrystalline LiBH4 and the two-phase analogue LiBH4 :Al2 O3 , which are prepared by ball milling, serve as interesting model systems to track the changes in NMR relaxation rates with respect to coarse-grained, thermodynamically stable LiBH4 . This reveals that interface (nano)engineering influences the hexagonal-to-orthorhombic phase transition and thus alters the ion-transport properties of Li in one- and two-phase LiBH4 towards higher diffusivities at lower temperatures. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Solution-processable glass LiI-Li4SnS4 superionic conductors for all-solid-state Li-ion batteries

    DOE PAGES

    Kern Ho Park; Oh, Dae Yang; Choi, Young Eun; ...

    2015-12-22

    The new, highly conductive (4.1 × 10–4 S cm–1 at 30 °C), highly deformable, and dry-air-stable glass 0.4LiI-0.6Li4SnS4 is prepared using a homogeneous methanol solution. Furthermore, the solution process enables the wetting of any exposed surface of the active materials with highly conductive solidified electrolytes (0.4LiI-0.6Li4SnS4), resulting in considerable improvements in electrochemical performances of these electrodes over conventional mixture electrodes.

  16. Synthesis, crystal structure, and TEM analysis of Sr19Li44 and Sr3Li2: a reinvestigation of the Sr-Li phase diagram.

    PubMed

    Smetana, Volodymyr; Kienle, Lorenz; Duppel, Viola; Simon, Arndt

    2015-02-02

    Two intermetallic phases in the Sr-Li system have been synthesized and structurally characterized. According to single-crystal X-ray diffraction data, Sr(19)Li(44) and Sr(3)Li(2) crystallize with tetragonal unit cells (Sr(19)Li(44), I-42d, a = 15.9122(7) Å, c = 31.831(2) Å, Z = 4, V = 8059(2) Å(3); Sr(3)Li(2), P42/mnm, a = 9.803(1) Å, c = 8.784(2) Å, Z = 4, V = 844.2(2) Å(3)). The first compound is isostructural with the recently discovered Ba(19)Li(44). Sr in Sr(19)Li(44) can be fully replaced by Ba with no changes to the crystal structure, whereas the substitution of Sr by Ca is only possible within a limited concentration range. Sr(3)Li(2) can be assigned to the Al(2)Zr(3) structure type. The crystal structure determination of Sr(19)Li(44) was complicated by multiple twinning. As an experimental highlight, an electron microscopy investigation of the highly moisture- and electron-beam-sensitive crystals was performed, enabling high-resolution imaging of the defect structure.

  17. Mass of {sup 11}Li from the {sup 1}H({sup 11}Li,{sup 9}Li){sup 3}H reaction

    SciTech Connect

    Roger, T.; Savajols, H.; Mittig, W.; Caamano, M.; Roussel-Chomaz, P.; Tanihata, I.; Alcorta, M.; Bandyopadhyay, D.; Bieri, R.; Buchmann, L.; Davids, B.; Galinski, N.; Howell, D.; Mills, W.; Mythili, S.; Openshaw, R.; Padilla-Rodal, E.; Ruprecht, G.; Sheffer, G.; Shotter, A. C.

    2009-03-15

    The mass of {sup 11}Li has been determined from Q-value measurements of the {sup 1}H({sup 11}Li,{sup 9}Li){sup 3}H reaction. The experiment was performed at TRIUMF laboratory with the GANIL active target MAYA. Energy-energy and angle-angle kinematics reconstruction give a Q value of 8.119(22) MeV for the reaction. The derived {sup 11}Li two-neutron separation energy is S{sub 2n}=363(22) keV.

  18. Thermal Stability of LiPF6 Salt and Li-ion Battery Electrolytes Containing LiPF6

    SciTech Connect

    Yang, Hui; Zhuang, Guorong V; Ross, Jr, Philip N

    2006-03-08

    The thermal stability of the neat LiPF6 salt and of 1 molal solutions of LiPF6 in prototypical Li-ion battery solvents was studied with thermogravimetric analysis (TGA) and on-line FTIR. Pure LiPF6 salt is thermally stable up to 380 K in a dry inert atmosphere, and its decomposition path is a simple dissociation producing LiF as solid and PF5 as gaseous products. In the presence of water (300 ppm) in the carrier gas, its decomposition onset temperature is lowered as a result of direct thermal reaction between LiPF6 and water vapor to form POF3 and HF. No new products were observed in 1 molal solutions of LiPF6 in EC, DMC and EMC by on-line TGA-FTIR analysis. The storage of the same solutions in sealed containers at 358 K for 300 420 hrs. did not produce any significant quantity of new products as well. In particular, noalkylflurophosphates were found in the solutions after storage at elevated temperature. In the absence of either an impurity like alcohol or cathode active material that may (or may not) act as a catalyst, there is no evidence of thermally induced reaction between LiPF6 and the prototypical Li-ion battery solvents EC, PC, DMC or EMC.

  19. G-LiHT: Goddard's LiDAR, Hyperspectral and Thermal Airborne Imager

    NASA Technical Reports Server (NTRS)

    Cook, Bruce; Corp, Lawrence; Nelson, Ross; Morton, Douglas; Ranson, Kenneth J.; Masek, Jeffrey; Middleton, Elizabeth

    2012-01-01

    Scientists at NASA's Goddard Space Flight Center have developed an ultra-portable, low-cost, multi-sensor remote sensing system for studying the form and function of terrestrial ecosystems. G-LiHT integrates two LIDARs, a 905 nanometer single beam profiler and 1550 nm scanner, with a narrowband (1.5 nanometers) VNIR imaging spectrometer and a broadband (8-14 micrometers) thermal imager. The small footprint (approximately 12 centimeters) LIDAR data and approximately 1 meter ground resolution imagery are advantageous for high resolution applications such as the delineation of canopy crowns, characterization of canopy gaps, and the identification of sparse, low-stature vegetation, which is difficult to detect from space-based instruments and large-footprint LiDAR. The hyperspectral and thermal imagery can be used to characterize species composition, variations in biophysical variables (e.g., photosynthetic pigments), surface temperature, and responses to environmental stressors (e.g., heat, moisture loss). Additionally, the combination of LIDAR optical, and thermal data from G-LiHT is being used to assess forest health by sensing differences in foliage density, photosynthetic pigments, and transpiration. Low operating costs (approximately $1 ha) have allowed us to evaluate seasonal differences in LiDAR, passive optical and thermal data, which provides insight into year-round observations from space. Canopy characteristics and tree allometry (e.g., crown height:width, canopy:ground reflectance) derived from G-LiHT data are being used to generate realistic scenes for radiative transfer models, which in turn are being used to improve instrument design and ensure continuity between LiDAR instruments. G-LiHT has been installed and tested in aircraft with fuselage viewports and in a custom wing-mounted pod that allows G-LiHT to be flown on any Cessna 206, a common aircraft in use throughout the world. G-LiHT is currently being used for forest biomass and growth estimation

  20. Riverine Li isotope fractionation in small mountainous rivers of Taiwan

    NASA Astrophysics Data System (ADS)

    Huang, K. F.; Liu, Y. H.; Wang, R. M.; Chung, C. H.; You, C. F.

    2016-12-01

    Riverine lithium (Li) and its isotopes became of increasing interest over the last decade due to its great potential as a tracer for silicate weathering processes and carbon cycle. However, little is known about the main controls on the riverine Li isotope fractionation in tropical small mountainous rivers (SMRs). Here we condcut the first deatiled study of the Li isotopic composition (δ7Li) of river-borne dissolved and solid materials in the SMRs around Taiwan to characterize behaviors of riverine Li and δ7Li in different geomorrphic setting and at wet/dry seasons. Riverine Li and δ7Li range from 0.15 to 6.37 μM with δ7Li of +8.6 to +18.2 ‰ at the wet season, and 0.23 to 18.8 μM with δ7Li of +8.2 to +20.3 ‰ at the dry season. Of special interest is that high dissolved δ7Li values are observed at the wet season and the downstream of the river catchments. By combining the multiple isotope systems and river chemistry, our results suggest that in the high-relief and tectonically active terrain, the high δ7Li values at the wet season are most likely controlled by more intense chemcical weathering, particularly by the greater extent of uptake of 6Li into secondary minierals during weathering. Seasonal variations in the dissolved loads and riverine δ7Li are also found and can be attributed to a greater contribution from carbonate weathering at the wet season, highlighting a different response of primary mineral dissolution/secondary mineral formation to climatic forcing in the SMRs of Taiwan.

  1. Preparation of Li-rich layered-layered type xLi2MnO3·(1-x)LiMnO2 nanorods and its electrochemical performance as cathode material for Li-ion battery

    NASA Astrophysics Data System (ADS)

    Yang, Fan; Zhang, Qinggang; Hu, Xiaohong; Peng, Tianyou; Liu, Jianqiang

    2017-06-01

    Layered-layered type xLi2MnO3·(1-x)LiMnO2 (x = 0.91, 0.78, 0.67, 0.54, 0.42, and 0.32) nanorods with a diameter of 100-200 nm and length of 400-1000 nm are prepared through a pyrolysis reduction process of monoclinic Li2MnO3 (m-Li2MnO3) nanorods. All the synthesized xLi2MnO3·(1-x)LiMnO2 nanorods exhibit the main characteristic diffraction peaks of m-Li2MnO3 in addition to some weak peaks attributable to m-LiMnO2 especially for those composites with x < 0.67. When used as cathode material of Li-ion battery, those xLi2MnO3·(1-x)LiMnO2 nanorods show an initial charge/discharge profile similar to the Li-rich solid solution in the voltage window of 2.0-4.8 V. The m-LiMnO2 portion in those synthesized composites can significantly enhance the reversible capacity but lower the cyclic stability, while the m-Li2MnO3 portion can improve the cyclic stability due to its retardation effect of the layered-to-spinel transformation during the charge/discharge processes, and thus xLi2MnO3·(1-x)LiMnO2 nanorods with x = 0.54 exhibits the best cyclic and rate performance since it contains appropriate m-Li2MnO3/m-LiMnO2 contents to balance the reversible capacity and Jahn-Teller effect. The present findings demonstrate an effective strategy for the development of low-cost pure Mn-based Li-rich layered cathode materials with adjustable reversible capacity, cyclic and rate performance by tailoring the composition.

  2. Enhanced Performance of Li|LiFePO4 Cells Using CsPF6 as an Electrolyte Additive

    SciTech Connect

    Xiao, Liang; Chen, Xilin; Cao, Ruiguo; Qian, Jiangfeng; Xiang, Hongfa; Zheng, Jianming; Zhang, Jiguang; Xu, Wu

    2015-10-20

    The practical application of lithium (Li) metal anode in rechargeable Li batteries is hindered by both the growth of Li dendrites and the low Coulombic efficiency (CE) during repeated charge/discharge cycles. Recently, we have discovered that CsPF6 as an electrolyte additive can significantly suppress Li dendrite growth and lead to highly compacted and well aligned Li nanorod structure during Li deposition on copper substrates. In this paper, the effect of CsPF6 additive on the performance of rechargeable Li metal batteries with lithium iron phosphate (LFP) cathode was further studied. Li|LFP coin cells with CsPF6 additive in electrolytes show well protected Li anode surface, decreased resistance, enhanced rate capability and extended cycling stability. In Li|LFP cells, the electrolyte with CsPF6 additive shows excellent long-term cycling stability (at least 500 cycles) at a charge current density of 0.5 mA cm-2 without internal short circuit. At high charge current densities, the effect of CsPF6 additive becomes less significant. Future work needs to be done to protect Li metal anode, especially at high charge current densities and for long cycle life.

  3. Enhancement of electrochemical behavior of nanostructured LiFePO4/Carbon cathode material with excess Li

    NASA Astrophysics Data System (ADS)

    Bazzi, K.; Nazri, M.; Naik, V. M.; Garg, V. K.; Oliveira, A. C.; Vaishnava, P. P.; Nazri, G. A.; Naik, R.

    2016-02-01

    We have synthesized carbon coated LiFePO4 (C-LiFePO4) and C-Li1.05FePO4 with 5 mol% excess Li via sol-gel method using oleic acid as a source of carbon for enhancing electronic conductivity and reducing the average particle size. Although the phase purity of the crystalline samples was confirmed by x-ray diffraction (XRD), the 57Fe Mössbauer spectroscopy analyses show the presence of ferric impurity phases in both stoichiometric and non-stoichiometric C-LiFePO4 samples. Transmission electron microscopy measurements show nanosized C-LiFePO4 particles uniformly covered with carbon, with average particle size reduced from ∼100 nm to ∼50 nm when excess lithium is used. Electrochemical measurements indicate a lower charge transfer resistance and better electrochemical performance for C-Li1.05FePO4 compared to that of C-LiFePO4. The aim of this work is to systematically analyze the nature of impurities formed during synthesis of LiFePO4 cathode material, and their impact on electrochemical performance. The correlation between the morphology, charge transfer resistance, diffusion coefficient and electrochemical performance of C-LiFePO4 and C- Li1.05FePO4 cathode materials are discussed.

  4. Enhanced performance of Li|LiFePO4 cells using CsPF6 as an electrolyte additive

    NASA Astrophysics Data System (ADS)

    Xiao, Liang; Chen, Xilin; Cao, Ruiguo; Qian, Jiangfeng; Xiang, Hongfa; Zheng, Jianming; Zhang, Ji-Guang; Xu, Wu

    2015-10-01

    The practical application of lithium (Li) metal anode in rechargeable Li batteries is hindered by both the growth of Li dendrites and the low Coulombic efficiency (CE) during repeated charge/discharge cycles. Recently, we have discovered that CsPF6 as an electrolyte additive can significantly suppress Li dendrite growth and lead to highly compacted and well aligned Li nanorod structures during Li deposition on copper substrates. In this paper, the effect of CsPF6 additive on the performance of rechargeable Li metal batteries with lithium iron phosphate (LFP) cathode is further studied. Li|LFP coin cells with CsPF6 additive in electrolytes show well protected Li anode surface, decreased resistance, enhanced rate capability and extended cycling stability. In Li|LFP cells, the electrolyte with CsPF6 additive shows excellent long-term cycling stability (at least 500 cycles) at a charge current density of 0.5 mA cm-2 without internal short circuit. At high charge current densities, the effect of CsPF6 additive becomes less significant. Future work needs to be done to protect Li metal anode, especially at high charge current densities and for long cycle life.

  5. Data mining of molecular dynamics data reveals Li diffusion characteristics in garnet Li7La3Zr2O12

    NASA Astrophysics Data System (ADS)

    Chen, Chi; Lu, Ziheng; Ciucci, Francesco

    2017-01-01

    Understanding Li diffusion in solid conductors is essential for the next generation Li batteries. Here we show that density-based clustering of the trajectories computed using molecular dynamics simulations helps elucidate the Li diffusion mechanism within the Li7La3Zr2O12 (LLZO) crystal lattice. This unsupervised learning method recognizes lattice sites, is able to give the site type, and can identify Li hopping events. Results show that, while the cubic LLZO has a much higher hopping rate compared to its tetragonal counterpart, most of the Li hops in the cubic LLZO do not contribute to the diffusivity due to the dominance of back-and-forth type jumps. The hopping analysis and local Li configuration statistics give evidence that Li diffusivity in cubic LLZO is limited by the low vacancy concentration. The hopping statistics also shows uncorrelated Poisson-like diffusion for Li in the cubic LLZO, and correlated diffusion for Li in the tetragonal LLZO in the temporal scale. Further analysis of the spatio-temporal correlation using site-to-site mutual information confirms the weak site dependence of Li diffusion in the cubic LLZO as the origin for the uncorrelated diffusion. This work puts forward a perspective on combining machine learning and information theory to interpret results of molecular dynamics simulations.

  6. Data mining of molecular dynamics data reveals Li diffusion characteristics in garnet Li7La3Zr2O12.

    PubMed

    Chen, Chi; Lu, Ziheng; Ciucci, Francesco

    2017-01-17

    Understanding Li diffusion in solid conductors is essential for the next generation Li batteries. Here we show that density-based clustering of the trajectories computed using molecular dynamics simulations helps elucidate the Li diffusion mechanism within the Li7La3Zr2O12 (LLZO) crystal lattice. This unsupervised learning method recognizes lattice sites, is able to give the site type, and can identify Li hopping events. Results show that, while the cubic LLZO has a much higher hopping rate compared to its tetragonal counterpart, most of the Li hops in the cubic LLZO do not contribute to the diffusivity due to the dominance of back-and-forth type jumps. The hopping analysis and local Li configuration statistics give evidence that Li diffusivity in cubic LLZO is limited by the low vacancy concentration. The hopping statistics also shows uncorrelated Poisson-like diffusion for Li in the cubic LLZO, and correlated diffusion for Li in the tetragonal LLZO in the temporal scale. Further analysis of the spatio-temporal correlation using site-to-site mutual information confirms the weak site dependence of Li diffusion in the cubic LLZO as the origin for the uncorrelated diffusion. This work puts forward a perspective on combining machine learning and information theory to interpret results of molecular dynamics simulations.

  7. Data mining of molecular dynamics data reveals Li diffusion characteristics in garnet Li7La3Zr2O12

    PubMed Central

    Chen, Chi; Lu, Ziheng; Ciucci, Francesco

    2017-01-01

    Understanding Li diffusion in solid conductors is essential for the next generation Li batteries. Here we show that density-based clustering of the trajectories computed using molecular dynamics simulations helps elucidate the Li diffusion mechanism within the Li7La3Zr2O12 (LLZO) crystal lattice. This unsupervised learning method recognizes lattice sites, is able to give the site type, and can identify Li hopping events. Results show that, while the cubic LLZO has a much higher hopping rate compared to its tetragonal counterpart, most of the Li hops in the cubic LLZO do not contribute to the diffusivity due to the dominance of back-and-forth type jumps. The hopping analysis and local Li configuration statistics give evidence that Li diffusivity in cubic LLZO is limited by the low vacancy concentration. The hopping statistics also shows uncorrelated Poisson-like diffusion for Li in the cubic LLZO, and correlated diffusion for Li in the tetragonal LLZO in the temporal scale. Further analysis of the spatio-temporal correlation using site-to-site mutual information confirms the weak site dependence of Li diffusion in the cubic LLZO as the origin for the uncorrelated diffusion. This work puts forward a perspective on combining machine learning and information theory to interpret results of molecular dynamics simulations. PMID:28094317

  8. Li-Metal-Free Prelithiation of Si-Based Negative Electrodes for Full Li-Ion Batteries.

    PubMed

    Zhou, Haitao; Wang, Xuehang; Chen, De

    2015-08-24

    Most of the high-capacity positive-electrode materials [for example, S, O2 (air), and MOx (M: V, Mn, Fe, etc.)] are Li-deficient and require the use of a Li-metal electrode or prelithiation. Herein, we report a novel electrolytic cell in which the Si electrode can be prelithiated in a well-controlled manner from Li-containing aqueous solution in a Li-metal-free way. MnOx/Si and S/Si Li-ion full cells were assembled by using the prelithiated Si negative electrodes, which resulted in high specific energies of 349 and 732 Wh kg(-1), respectively. The MnOx/Si full cell still retains 138 Wh kg(-1) even at a high specific power of 1710 W kg(-1). This is the first report of a whole process of making a full Li-ion battery with both Li-deficient electrodes without the use of Li metal as the Li source. This novel prelithiation process, with high controllability, no short circuiting, and an abundant Li source, is expected to contribute significantly to the development of safe, green, and powerful Li-ion batteries. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Li interactions with the B40 fullerene and its application in Li-ion batteries: DFT studies

    NASA Astrophysics Data System (ADS)

    Moradi, Morteza; Bagheri, Zargham; Bodaghi, Ali

    2017-05-01

    The interaction of Li and Li+ with a B40 all-boron fullerene was theoretically investigated at the B3LYP, and Minnesota 2006 levels of theory. It was found that, unexpectedly, the interaction Li+ cation with the electron deficient B40 fullerene is stronger than the Li atom. It indicates that the B40 fullerene does not act as a conventional Lewis acid because of its highly correlated structure. Frontier molecular orbitals, partial density of states, and natural bond orbital analyses were used to discuss this unusual behavior. Our calculations indicate that this behavior makes the B40 fullerene more appropriate for application in the Li-ion batteries as anode material. The calculated cell voltage is about 530 mV. Also, it was found that Hartree Fock (HF) exchange percentage of density functionals has a reverse effect on the adsorption energies of Li and Li+. This energy is increased and decreased, respectively, for Li+ and Li adsorptions by increasing %HF exchange. Finally, a potential energy surface for Li and Li+ penetration into B40 fullerene was predicted.

  10. Synthesis and characterization of Carbon Nano Fiber/LiFePO 4 composites for Li-ion batteries

    NASA Astrophysics Data System (ADS)

    Bhuvaneswari, M. S.; Bramnik, N. N.; Ensling, D.; Ehrenberg, H.; Jaegermann, W.

    Carbon Nano Fibers (CNFs) coated with LiFePO 4 particles have been prepared by a non-aqueous sol-gel technique. The functionalization of the CNFs by HNO 3 acid treatment has been confirmed by Raman and XPS analyses. The samples pure LiFePO 4 and LiFePO 4-CNF have been characterized by XRD, SEM, RAMAN, XPS and electrochemical analysis. The LiFePO 4-CNF sample shows better electrochemical performance compared to as-prepared LiFePO 4. LiFePO 4-CNF (10 wt.%) delivers a higher specific capacity (∼140 mAh g -1) than LiFePO 4 with carbon black (25 wt.%) added after synthesis (∼120 mAh g -1) at 0.1C.

  11. Influence of surface modification of LiCoO2 by organic compounds on electrochemical and thermal properties of Li/LiCoO2 rechargeable cells

    NASA Astrophysics Data System (ADS)

    Takeuchi, Takashi; Kyuna, Tomohiro; Morimoto, Hideyuki; Tobishima, Shin-ichi

    2011-03-01

    LiCoO2 is the most famous positive electrode (cathode) for lithium ion cells. When LiCoO2 is charged at high charge voltages far from 4.2 V, cycleability of LiCoO2 becomes worse. Causes for this deterioration are instability of pure LiCoO2 crystalline structure and an oxidation of electrolyte solutions LiCoO2 at higher charge voltages. This electrolyte oxidation accompanies with the partial reduction of LiCoO2. We think more important factor is the oxidation of electrolyte solutions. In this work, influence of 10 organic compounds on electrochemical and thermal properties of LiCoO2 cells was examined as electrolyte additives. As a base electrolyte solution, 1 M (M: mol L-1) LiPF6-ethylene carbonate (EC)/ethylmethyl carbonate (EMC) (mixing volume ratio = 3:7) was used. These compounds are o-terphenyl (o-TP), Ph-X (CH3)n (n = 1 or 2, X = N, O or S) compounds, adamantyl toluene compounds, furans and thiophenes. These additives had the oxidation potentials (Eox) between 3.4 and 4.7 V vs. Li/Li+. These Eox values were lower than that (6.30 V vs. Li/Li+) of the base electrolyte. These additives are oxidized on LiCoO2 during charge of the LiCoO2 cells. Oxidation products suppress the excess oxidation of electrolyte solutions on LiCoO2. As a typical example of these organic compounds, o-TP (Eox: 4.52 V) was used to check the fundamental properties of these organic additives. Charge-discharge cycling tests were carried out for the Li/LiCoO2 cells with and without o-TP. Constant current charge at 4.5 V is mainly used as a charge method. Cells with 0.1 wt.% o-TP exhibited slightly better cycling performance and lower polarization than those without additives. Lower polarization arises from a decrease in a resistance of interface between electrolyte solutions and LiCoO2 by surface film formation resulted from oxidation of o-TP. Oxidation products were found by mass spectroscopy analysis to be mixture of several polycondensation compounds made from two to four terphenly

  12. Comparative study of EC/DMC LiTFSI and LiPF 6 electrolytes for electrochemical storage

    NASA Astrophysics Data System (ADS)

    Dahbi, Mouad; Ghamouss, Fouad; Tran-Van, François; Lemordant, Daniel; Anouti, Mérièm

    Lithium bis(trifluoromethane sulfonyl) imide (LiTFSI) salt are potentially a good alternative to LiPF 6 since it could both improve the chemical and thermal stability as salt for electrolyte. This work presents a systematic comparative study between LiPF 6 and LiTFSI in a mixture of EC/DMC on the basis of some of their physicochemical properties. Transport properties (viscosity and conductivity) are compared at various temperatures from -20 to 80 °C. Using Walden rule, we have demonstrated that LiTFSI 1 M in EC/DMC is more ionic than LiPF 6 1 M in the same binary solvent. Moreover, the electrochemical storage properties of an activated carbon electrode were investigated in EC/DMC mixture containing LiTFSI or LiPF 6. The specific capacitance C s of activated carbon was determined from the Galvanostatic charge-discharge curve between 2 and 3.7 V, at low current densities. The capacitance values were found to be 100 and 90 F g -1 respectively for LiTFSI and LiPF 6 electrolytes at 2 mA g -1. On the basis of the physicochemical and electrochemical measurements, we have correlated the improvement of the specific capacitance with activated carbon to the increase of the ionicity of the LiTFSI salt in EC/DMC binary system. The drawback concerning the corrosion of aluminium collectors was resolved by adding a few percentage of LiPF 6 (1%) in the binary electrolyte. Finally, we have studied the electrochemical behavior of intercalation-deintercalation of lithium in the graphite electrode with EC/DMC + LiTFSI as electrolyte. Results of this study indicate that the realization of asymmetric graphite/activated carbon supercapacitors with LiFTSI based electrolyte is possible.

  13. High current LiSOCl2 batteries

    NASA Astrophysics Data System (ADS)

    Debiccari, Daniel J.

    The paper describes cell construction, performance, and safety aspects of two high-rate active Li/SOCl2 batteries designed to operate at current densities as high as 26 mA/sq cm in pulse modes of 20 millisec to several minutes. Both cell designs employ a flat-plate arrangement of electrodes, a cyanoacrylate-coated anode, a bonded carbon/copper cathode, and a 1.6 M electrolyte. The major differences of the two designs are the size of the cell and the method of anode attachment. The two batteries were shown to provide over 10 times the mission life of the Ni-Cd batteries; thus, they will eliminate the logistic problems associated with the recharge requirements of the latter. In addition, a replacement of the Ni-Cd battery types with lighter Li-thionyl chloride batteries will significantly reduce battery weight and increase its capacity.

  14. Composite Solid Electrolyte Containing Li+- Conducting Fibers

    NASA Technical Reports Server (NTRS)

    Appleby, A. John; Wang, Chunsheng; Zhang, Xiangwu

    2006-01-01

    Improved composite solid polymer electrolytes (CSPEs) are being developed for use in lithium-ion power cells. The matrix components of these composites, like those of some prior CSPEs, are high-molecular-weight dielectric polymers [generally based on polyethylene oxide (PEO)]. The filler components of these composites are continuous, highly-Li(+)-conductive, inorganic fibers. PEO-based polymers alone would be suitable for use as solid electrolytes, were it not for the fact that their room-temperature Li(+)-ion conductivities lie in the range between 10(exp -6) and 10(exp -8) S/cm, too low for practical applications. In a prior approach to formulating a CSPE, one utilizes nonconductive nanoscale inorganic filler particles to increase the interfacial stability of the conductive phase. The filler particles also trap some electrolyte impurities. The achievable increase in conductivity is limited by the nonconductive nature of the filler particles.

  15. Metastable structure of Li13Si4

    NASA Astrophysics Data System (ADS)

    Gruber, Thomas; Bahmann, Silvia; Kortus, Jens

    2016-04-01

    The Li13Si4 phase is one out of several crystalline lithium silicide phases, which is a potential electrode material for lithium ion batteries and contains a high theoretical specific capacity. By means of ab initio methods like density functional theory (DFT) many properties such as heat capacity or heat of formation can be calculated. These properties are based on the calculation of phonon frequencies, which contain information about the thermodynamical stability. The current unit cell of "Li13Si4" given in the ICSD database is unstable with respect to DFT calculations. We propose a modified unit cell that is stable in the calculations. The evolutionary algorithm EVO found a structure very similar to the ICSD one with both of them containing metastable lithium positions. Molecular dynamic simulations show a phase transition between both structures where these metastable lithium atoms move. This phase transition is achieved by a very fast one-dimensional lithium diffusion and stabilizes this phase.

  16. Li + ion diffusion in nanoscale alumina coatings

    NASA Astrophysics Data System (ADS)

    Johannes, Michelle; Bernstein, Noam

    Nanoscale coatings of alumina are used to stabilize surfaces for a variety of technologies. Diffusion of ions through these coatings is of primary importance: in some cases, diffusion is unwanted (e.g. corrosion) and in others (e.g. electrode materials), it is necessary. In this work DFT and AIMD calculations are used to investigate Li+ ion diffusion through a nano-layer of alumina, examining the phase (alpha, gamma, and amorphous), ion concentration, and electron count dependence. We look at the role of the surface itself in promoting diffusion. One of our main findings is that as the number of ions or charge increases, the diffusivity rises. We show how our data can explain electrochemical data from coated LiCoO2 cathodes and may point toward better and more efficient coatings for stabilizing electrodes.

  17. LiHo(PO3)4

    PubMed Central

    Ben Zarkouna, Emna; Driss, Ahmed; Férid, Mokhtar

    2009-01-01

    Lithium holmium(III) polyphosphate(V), LiHo(PO3)4, belongs to the type I of polyphosphates with general formula ALn(PO3)4, where A is a monovalent cation and Ln is a trivalent rare earth cation. In the crystal structure, the polyphosphate chains spread along the b-axis direction, with a repeat period of four tetra­hedra and 21 inter­nal symmetry. The Li and Ho atoms are both located on twofold rotation axes and are surrounded by four and eight O atoms, leading to a distorted tetra­hedral and dodeca­hedral coordination, respectively. The HoO8 polyhedra are isolated from each other, the closest Ho⋯Ho distance being 5.570 (1) Å. PMID:21581738

  18. Li, B and N in ancient materials

    NASA Astrophysics Data System (ADS)

    Fink, D.

    1983-12-01

    The content of B and Li is examined in several ancient and, for comparison, in modern objects for techological and household use (glasses, coins, nails, needles, bells, shells, bones, pitch, minerals). For most samples the B content is proportional to the Li content, the proportionality factor ranging from 1 to 6. The data scatteringroups of examined species are given. It is known that the N content of bones decreases with age due to decomposition of organic materials. This is confirmed, and simultaneously an enrichment of B was observed for ancient bones, probably due to salt transport from the surrounding soil into the bones. Coins frequently show a nitrogen enriched layer on their surfaces due to corrosion. B surface contaminations are sometimes observed for glasses and mother-of-pearl.

  19. Li7La3Zr2O12 Interface Modification for Li Dendrite Prevention.

    PubMed

    Tsai, Chih-Long; Roddatis, Vladimir; Chandran, C Vinod; Ma, Qianli; Uhlenbruck, Sven; Bram, Martin; Heitjans, Paul; Guillon, Olivier

    2016-04-27

    Al-contaminated Ta-substituted Li7La3Zr2O12 (LLZ:Ta), synthesized via solid-state reaction, and Al-free Ta-substituted Li7La3Zr2O12, fabricated by hot-press sintering (HP-LLZ:Ta), have relative densities of 92.7% and 99.0%, respectively. Impedance spectra show the total conductivity of LLZ:Ta to be 0.71 mS cm(-1) at 30 °C and that of HP-LLZ:Ta to be 1.18 mS cm(-1). The lower total conductivity for LLZ:Ta than HP-LLZ:Ta was attributed to the higher grain boundary resistance and lower relative density of LLZ:Ta, as confirmed by their microstructures. Constant direct current measurements of HP-LLZ:Ta with a current density of 0.5 mA cm(-2) suggest that the short circuit formation was neither due to the low relative density of the samples nor the reduction of Li-Al glassy phase at grain boundaries. TEM, EELS, and MAS NMR were used to prove that the short circuit was from Li dendrite formation inside HP-LLZ:Ta, which took place along the grain boundaries. The Li dendrite formation was found to be mostly due to the inhomogeneous contact between LLZ solid electrolyte and Li electrodes. By flatting the surface of the LLZ:Ta pellets and using thin layers of Au buffer to improve the contact between LLZ:Ta and Li electrodes, the interface resistance could be dramatically reduced, which results in short-circuit-free cells when running a current density of 0.5 mA cm(-2) through the pellets. Temperature-dependent stepped current density galvanostatic cyclings were also carried out to determine the critical current densities for the short circuit formation. The short circuit that still occurred at higher current density is due to the inhomogeneous dissolution and deposition of metallic Li at the interfaces of Li electrodes and LLZ solid electrolyte when cycling the cell at large current densities.

  20. Core excitation of Li by electron impact

    SciTech Connect

    Tiwary, S.N.

    1985-07-01

    Cross sections for the excitation of a core electron, which leads to autoionization, in lithium (Li) atomic system by electron impact have been calculated with use of the single-configuration Hartree-Fock wave function within the asymptotic Green's-function approximation (AGFA) in the low-bombarding-energy region. Comparison is made with available results. Our investigation demonstrates that the AGFA supports the R-matrix as well as the distorted-wave Born-approximation behavior.

  1. A new active Li-Mn-O compound for high energy density Li-ion batteries

    NASA Astrophysics Data System (ADS)

    Freire, M.; Kosova, N. V.; Jordy, C.; Chateigner, D.; Lebedev, O. I.; Maignan, A.; Pralong, V.

    2016-02-01

    The search for new materials that could improve the energy density of Li-ion batteries is one of today’s most challenging issues. Many families of transition metal oxides as well as transition metal polyanionic frameworks have been proposed during the past twenty years. Among them, manganese oxides, such as the LiMn2O4 spinel or the overlithiated oxide Li[Li1/3Mn2/3]O2, have been intensively studied owing to the low toxicity of manganese-based materials and the high redox potential of the Mn3+/Mn4+ couple. In this work, we report on a new electrochemically active compound with the `Li4Mn2O5’ composition, prepared by direct mechanochemical synthesis at room temperature. This rock-salt-type nanostructured material shows a discharge capacity of 355 mAh g-1, which is the highest yet reported among the known lithium manganese oxide electrode materials. According to the magnetic measurements, this exceptional capacity results from the electrochemical activity of the Mn3+/Mn4+ and O2-/O- redox couples, and, importantly, of the Mn4+/Mn5+ couple also.

  2. Probing the capacity loss of Li3VO4 anode upon Li insertion and extraction

    NASA Astrophysics Data System (ADS)

    Liao, Chaoyi; Wen, Yanwei; Shan, Bin; Zhai, Tianyou; Li, Huiqiao

    2017-04-01

    Fast progresses have been made for Li3VO4 since it is firstly reported as an anode material in 2013. However, most of current works focus on its performance improvement in capacity, rate and cycle capability, little study has been done to address its charge/discharge mechanism. Herein, we try to give a comprehensive understanding of its charge/discharge behaviours and capacity loss mechanism. By controlling the depth of discharge, it is found that the first irreversible capacity loss is related to the formation of SEI film as well as the structure distortion initiated by first lithiation. And the cycle performance of Li3VO4 can also be influenced by the discharge depth. First principle calculation is also performed to predict the structure changes of Li3VO4 upon different Li insertion amounts, and the results prove that the volume expansion and crystal distortion becomes more irreversibly at deep discharge. Along with cycle number, the accumulated structure deterioration results in the decline of material crystallization and structure orders, leading to capacity loss upon cycles. Based on the systematically analysis, future optimization of Li3VO4 are also proposed, for instance, the interface modification by surface coating or optimization of electrolyte components, and structure stabilization by ion doping.

  3. A new active Li-Mn-O compound for high energy density Li-ion batteries.

    PubMed

    Freire, M; Kosova, N V; Jordy, C; Chateigner, D; Lebedev, O I; Maignan, A; Pralong, V

    2016-02-01

    The search for new materials that could improve the energy density of Li-ion batteries is one of today's most challenging issues. Many families of transition metal oxides as well as transition metal polyanionic frameworks have been proposed during the past twenty years. Among them, manganese oxides, such as the LiMn2O4 spinel or the overlithiated oxide Li[Li1/3Mn2/3]O2, have been intensively studied owing to the low toxicity of manganese-based materials and the high redox potential of the Mn(3+)/Mn(4+) couple. In this work, we report on a new electrochemically active compound with the 'Li4Mn2O5' composition, prepared by direct mechanochemical synthesis at room temperature. This rock-salt-type nanostructured material shows a discharge capacity of 355 mAh g(-1), which is the highest yet reported among the known lithium manganese oxide electrode materials. According to the magnetic measurements, this exceptional capacity results from the electrochemical activity of the Mn(3+)/Mn(4+) and O(2-)/O(-) redox couples, and, importantly, of the Mn(4+)/Mn(5+) couple also.

  4. Thermal and Cycle-Life Behavior of Commercial Li-ion and Li-Polymer Cells

    NASA Technical Reports Server (NTRS)

    Zimmerman, Albert H.; Quinzio, M. V.

    2001-01-01

    Accelerated and real-time LEO cycle-life test data will be presented for a range of commercial Li-ion and Li-polymer (gel type) cells indicating the ranges of performance that can be obtained, and the performance screening tests that must be done to assure long life. The data show large performance variability between cells, as well as a highly variable degradation signature during non-cycling periods within the life tests. High-resolution Dynamic Calorimetry data will be presented showing the complex series of reactions occurring within these Li cells as they are cycled. Data will also be presented for cells being tested using an Adaptive Charge Control Algorithm (ACCA) that continuously adapts itself to changes in cell performance, operation, or environment to both find and maintain the optimum recharge over life. The ACCA has been used to prevent all unneeded overcharge for Li cells, NiCd cells and NiH2 cells. While this is important for all these cell types, it is most critical for Li-ion cells, which are not designed with electrochemical tolerance for overcharge.

  5. Interfacial Li-ion localization in hierarchical carbon anodes

    SciTech Connect

    McNutt, Nicholas W.; Rios, Orlando; Maroulas, Vasileios; Keffer, David J.

    2016-10-24

    An understanding of the nanoscale structure and energetics of carbon composites is critical for their applications in electric energy storage. Here, we study the properties of carbon anodes synthesized from low-cost renewable lignin biopolymers for use in energy storage applications such as Li-ion batteries. The anodes possess both nanoscale and mesoscale order, consisting of carbon nanocrystallites distributed within an amorphous carbon matrix. Molecular dynamics simulations of an experimentally validated model of the anode is used to elucidate the nature of Li-ion storage. We report the discovery of a novel mechanism of Li-ion storage, one in which Li+ is not intercalated between layers of carbon (as is the case in graphitic anodes), but rather is localized at the interface of crystalline carbon domains. In particular, the effects of Li-ion binding energy on the Li-Li, Li-H, and Li-C pair distribution functions are revealed, along with the effect on charge distribution. As a result, the atomic environments surrounding the Li-ions are grouped on the basis of ion energy and then convolved into archetypal structural motifs that reveal deep insight into the geometry of ion localization in disordered systems.

  6. Interfacial Li-ion localization in hierarchical carbon anodes

    DOE PAGES

    McNutt, Nicholas W.; Rios, Orlando; Maroulas, Vasileios; ...

    2016-10-24

    An understanding of the nanoscale structure and energetics of carbon composites is critical for their applications in electric energy storage. Here, we study the properties of carbon anodes synthesized from low-cost renewable lignin biopolymers for use in energy storage applications such as Li-ion batteries. The anodes possess both nanoscale and mesoscale order, consisting of carbon nanocrystallites distributed within an amorphous carbon matrix. Molecular dynamics simulations of an experimentally validated model of the anode is used to elucidate the nature of Li-ion storage. We report the discovery of a novel mechanism of Li-ion storage, one in which Li+ is not intercalatedmore » between layers of carbon (as is the case in graphitic anodes), but rather is localized at the interface of crystalline carbon domains. In particular, the effects of Li-ion binding energy on the Li-Li, Li-H, and Li-C pair distribution functions are revealed, along with the effect on charge distribution. As a result, the atomic environments surrounding the Li-ions are grouped on the basis of ion energy and then convolved into archetypal structural motifs that reveal deep insight into the geometry of ion localization in disordered systems.« less

  7. Electrochemical performance of LiNi0.4Co0.2Mn0.4O2 prepared by different molten salt flux: LiNO3-LiCl and LiNO3-KNO3

    NASA Astrophysics Data System (ADS)

    Satyanarayana, M.; James, Joseph; U. V., Varadaraju

    2017-10-01

    LiNi0.4Co0.2Mn0.4O2 material synthesized at different temperatures by using LiNO3-LiCl and LiNO3-KNO3 molten salt as a reaction medium. The phase purity of the samples obtained by powder X-ray diffraction measurement which suggests layered α-NaFeO2 type is obtained at 800-900 °C using LiNO3-LiCl flux and at 750-850 °C using LiNO3-KNO3 flux. The surface morphology change with flux media at different temperature are obtained by scanning electron microscopy analysis. The galvanostatic cycling results show that the high stable reversible discharge capacity of 155 (±3) mAh g-1 obtained for treated compound at 900 °C for 1 h (using LiNO3-LiCl) with coloumbic efficiency of 99%. The reversible discharge capacity of 140 and 130 (±3) mAh g-1 obtained for treated compound at 750 and 850 °C, respectively (using LiNO3-KNO3).

  8. High performance MCFC using Li/Na electrolyte

    SciTech Connect

    Donado, R.A.; Ong, E.T.; Sishtla, C.I.

    1995-08-01

    The substitution of a lithium/ sodium carbonate (Li/Na) mixture for the lithium/potassium carbonate (Li/K) electrolyte used in MCFCs holds the promise of higher ionic conductivity, higher exchange current density at both electrodes, lower vapor pressure, and lower cathode dissolution rates. However, when the substitution is made in cells optimized for use with the Li/K electrolyte, the promised increase in performance is not realized. As a consequence the literature contains conflicting data with regard to the performance, compositional stability, and chemical reactivity of the Li/Na electrolyte. Experiments conducted at the Institute of Gas Technology (IGT) concluded that the source of the problem is the different wetting characteristics of the two electrolytes. Electrode pore structures optimized for use with Li/K do not work well with Li/Na. Using proprietary methods and materials, IGT was able to optimize a set of electrodes for the Li/Na electrolyte. Experiments conducted in bench-scale cells have confirmed the superior performance of the Li/Na electrolyte compared to the Li/K electrolyte. The Li/Na cells exhibited a 5 to 8 percent improvement in overall performance, a substantial decrease in the rate of cathode dissolution, and a decreased decay rate. The longest running cell has logged over 13,000 hours of operation with a decay rate of less than 2 mV/1000 hours.

  9. Li2OHCl crystalline electrolyte for stable metallic lithium anodes

    DOE PAGES

    Hood, Zachary D.; Wang, Hui; Samuthira Pandian, Amaresh; ...

    2016-01-22

    In a classic example of stability from instability, we show that Li2OHCl solid electrolyte forms a stable solid electrolyte interface (SEI) with metallic lithium anode. The Li2OHCl solid electrolyte can be readily achieved through simple mixing of air-stable LiOH and LiCl precursors with a mild processing temperature under 400 °C. Additionally, we show that continuous, dense Li2OHCl membranes can be fabricated at temperatures less than 400 °C, standing in great contrast to current processing temperatures of over 1600 °C for most oxide-based solid electrolytes. The ionic conductivity and Arrhenius activation energy were explored for the LiOH-LiCl system of crystalline solidmore » electrolytes where Li2OHCl with increased crystal defects was found to have the highest ionic conductivity and reasonable Arrhenius activation energy. The Li2OHCl solid electrolyte displays stability against metallic lithium, even in extreme conditions past the melting point of lithium metal. Furthermore, to understand this excellent stability, we show that SEI formation is critical in stabilizing the interface between metallic lithium and the Li2OHCl solid electrolyte.« less

  10. Insight into sulfur reactions in Li-S batteries.

    PubMed

    Xu, Rui; Belharouak, Ilias; Zhang, Xiaofeng; Chamoun, Rita; Yu, Cun; Ren, Yang; Nie, Anmin; Shahbazian-Yassar, Reza; Lu, Jun; Li, James C M; Amine, Khalil

    2014-12-24

    Understanding and controlling the sulfur reduction species (Li2Sx, 1 ≤ x ≤ 8) under realistic battery conditions are essential for the development of advanced practical Li-S cells that can reach their full theoretical capacity. However, it has been a great challenge to probe the sulfur reduction intermediates and products because of the lack of methods. This work employed various ex situ and in situ methods to study the mechanism of the Li-S redox reactions and the properties of Li2Sx and Li2S. Synchrotron high-energy X-ray diffraction analysis used to characterize dry powder deposits from lithium polysulfide solution suggests that the new crystallite phase may be lithium polysulfides. The formation of Li2S crystallites with a polyhedral structure was observed in cells with both the conventional (LiTFSI) electrolyte and polysulfide-based electrolyte. In addition, an in situ transmission electron microscopy experiment observed that the lithium diffusion to sulfur during discharge preferentially occurred at the sulfur surface and formed a solid Li2S crust. This may be the reason for the capacity fade in Li-S cells (as also suggested by EIS experiment in Supporting Information ). The results can be a guide for future studies and control of the sulfur species and meanwhile a baseline for approaching the theoretical capacity of the Li-S battery.

  11. Computational Studies of Solubilities of LiO{sub 2} and Li{sub 2}O{sub 2} in Aprotic Solvents.

    SciTech Connect

    Cheng, Lei; Redfern, Paul C.; Lau, Kah Chun; Assary, Rajeev S.; Narayanan, Badri; Curtiss, Larry A.

    2017-01-01

    Knowledge of the solubilities of Li2O2 and LiO2 in aprotic solvents is important for insight into the discharge and charge processes of Li-O2 batteries, but these quantities are not well known. In this contribution, the solvation free energies of molecular LiO2 and Li2O2 in various organic solvents were calculated using various explicit and implicit solvent models, as well as ab initio molecular dynamics (AIMD) methods. Best estimates for the solvation energies from these calculations along with calculated lattice energies of Li2O2 and LiO2 were used to determine the solubility of bulk LiO2 and Li2O2. The computed solubility of LiO2 (1.8 × 10-2 M) is about 15 orders higher than that of Li2O2 (2.0 × 10-17 M) due to a much less negative lattice energy of bulk LiO2 compared to that of Li2O2. The difference in solubilities between LiO2 and Li2O2 likely will affect the nucleation and growth mechanisms and resulting morphologies of the products formed during battery discharge, influencing the performance of the battery cell. The calculated LiO2 and Li2O2 solubilities provide important information for fundamental studies of discharge and charge chemistries in Li-O2 batteries.

  12. Computational Studies of Solubilities of LiO{sub 2} and Li{sub 2}O{sub 2} in Aprotic Solvents.

    DOE PAGES

    Cheng, Lei; Redfern, Paul C.; Lau, Kah Chun; ...

    2017-01-01

    Knowledge of the solubilities of Li2O2 and LiO2 in aprotic solvents is important for insight into the discharge and charge processes of Li-O2 batteries, but these quantities are not well known. In this contribution, the solvation free energies of molecular LiO2 and Li2O2 in various organic solvents were calculated using various explicit and implicit solvent models, as well as ab initio molecular dynamics (AIMD) methods. Best estimates for the solvation energies from these calculations along with calculated lattice energies of Li2O2 and LiO2 were used to determine the solubility of bulk LiO2 and Li2O2. The computed solubility of LiO2 (1.8more » × 10-2 M) is about 15 orders higher than that of Li2O2 (2.0 × 10-17 M) due to a much less negative lattice energy of bulk LiO2 compared to that of Li2O2. The difference in solubilities between LiO2 and Li2O2 likely will affect the nucleation and growth mechanisms and resulting morphologies of the products formed during battery discharge, influencing the performance of the battery cell. The calculated LiO2 and Li2O2 solubilities provide important information for fundamental studies of discharge and charge chemistries in Li-O2 batteries.« less

  13. Spectroscopy of Li9Λ by electroproduction

    NASA Astrophysics Data System (ADS)

    Urciuoli, G. M.; Cusanno, F.; Marrone, S.; Acha, A.; Ambrozewicz, P.; Aniol, K. A.; Baturin, P.; Bertin, P. Y.; Benaoum, H.; Blomqvist, K. I.; Boeglin, W. U.; Breuer, H.; Brindza, P.; Bydžovský, P.; Camsonne, A.; Chang, C. C.; Chen, J.-P.; Choi, Seonho; Chudakov, E. A.; Cisbani, E.; Colilli, S.; Coman, L.; Craver, B. J.; De Cataldo, G.; de Jager, C. W.; De Leo, R.; Deur, A. P.; Ferdi, C.; Feuerbach, R. J.; Folts, E.; Fratoni, R.; Frullani, S.; Garibaldi, F.; Gayou, O.; Giuliani, F.; Gomez, J.; Gricia, M.; Hansen, J. O.; Hayes, D.; Higinbotham, D. W.; Holmstrom, T. K.; Hyde, C. E.; Ibrahim, H. F.; Iodice, M.; Jiang, X.; Kaufman, L. J.; Kino, K.; Kross, B.; Lagamba, L.; LeRose, J. J.; Lindgren, R. A.; Lucentini, M.; Margaziotis, D. J.; Markowitz, P.; Meziani, Z. E.; McCormick, K.; Michaels, R. W.; Millener, D. J.; Miyoshi, T.; Moffit, B.; Monaghan, P. A.; Moteabbed, M.; Camacho, C. Muñoz; Nanda, S.; Nappi, E.; Nelyubin, V. V.; Norum, B. E.; Okasyasu, Y.; Paschke, K. D.; Perdrisat, C. F.; Piasetzky, E.; Punjabi, V. A.; Qiang, Y.; Reimer, P. E.; Reinhold, J.; Reitz, B.; Roche, R. E.; Rodriguez, V. M.; Saha, A.; Santavenere, F.; Sarty, A. J.; Segal, J.; Shahinyan, A.; Singh, J.; Širca, S.; Snyder, R.; Solvignon, P. H.; Sotona, M.; Subedi, R.; Sulkosky, V. A.; Suzuki, T.; Ueno, H.; Ulmer, P. E.; Veneroni, P.; Voutier, E.; Wojtsekhowski, B. B.; Zheng, X.; Zorn, C.; Jefferson Lab Hall A Collaboration

    2015-03-01

    Background: In the absence of accurate data on the free two-body hyperon-nucleon interaction, the spectra of hypernuclei provides information on the details of the effective hyperon-nucleon interaction. Purpose: To obtain a high-resolution binding-energy spectrum for the 9Be (e ,e'K+) Li9Λ reaction. Method: Electroproduction of the hypernucleus Li9Λ has been studied for the first time with sub-MeV energy resolution in Hall A at Jefferson Lab on a 9Be target. In order to increase the counting rate and to provide unambiguous kaon identification, two superconducting septum magnets and a ring imaging Cherenkov detector were added to the Hall A standard equipment. Results: The cross section to low-lying states of Li9Λ is concentrated within 3 MeV of the ground state and can be fit with four peaks. The positions of the doublets agree with theory while a disagreement could exist with respect to the relative strengths of the peaks in the doublets. The Λ separation energy, BΛ, of 8.36 ±0.08 (stat.) ±0.08 (syst.) MeV was measured, in agreement with an earlier experiment.

  14. Endurance testing with Li/Na electrolyte

    SciTech Connect

    Ong, E.T.; Remick, R.J.; Sishtla, C.I.

    1996-12-31

    The Institute of Gas Technology (IGT), under subcontract to M-C Power Corporation under DOE funding, has been operating bench-scale fuel cells to investigate the performance and endurance issues of the Li/Na electrolyte because it offers higher ionic conductivity, higher exchange current densities, lower vapor pressures, and lower cathode dissolution rates than the Li/K electrolyte. These cells have continued to show higher performance and lower decay rates than the Li/K cells since the publication of our two previous papers in 1994. In this paper, test results of two long-term 100-cm{sup 2} bench scale cells are discussed. One cell operated continuously at 160 mA/cm{sup 2} for 17,000 hours with reference gases (60H{sub 2}/20CO{sub 2}/20H{sub 2}O fuel at 75% utilization and 30CO{sub 2}/70 air oxidant humidified at room temperature at 50% utilization). The other cell operated at 160 mA/cm{sup 2} for 6900 hours at 3 atm with system gases (64H{sub 2}/16CO{sub 2}/20H{sub 2}O at 75% utilization and an M-C Power system-defined oxidant at 40% utilization). Both cells have shown the highest performance and longest endurance among IGT cells operated to date.

  15. Composite Solid Electrolyte for Li Battery Applications

    NASA Technical Reports Server (NTRS)

    Nagasubramanian, G.; Attia, A. I.; Halpert, G.; Peled, E.

    1993-01-01

    The electrochemical, bulk and interfacial properties of the polyethylene oxide (PEO) based composite solid electrolyte (CSE) comprising LiI, PEO, and Al2O3 have been evaluated for Li battery applications. The bulk interfacial and transport properties of the CSEs seem to strongly depend on the alumina particle size. For the CSE films with 0.05 micron alumina while the bulk conductivity is around 10(exp -4) (mho/cm) at 103 C, the Li ion transport number seems to be close to unity at the same temperature. Compared to the PEO electrolyte this polymer composite electrolyte seems to exhibit robust mechanical and interfacial properties. We have studied three different films with three different alumina sizes in the range 0.01-0.3 micron. Effects of Al2O3 particle size on the electrochemical performance of polymer composite electrolyte is discussed. With TiS2 as cathode a 10 mAh small capacity cell was charged and discharged at C/40 and C/20 rates respectively.

  16. Composite Solid Electrolyte for Li Battery Applications

    NASA Technical Reports Server (NTRS)

    Nagasubramanian, G.; Attia, A. I.; Halpert, G.; Peled, E.

    1993-01-01

    The electrochemical, bulk and interfacial properties of the polyethylene oxide (PEO) based composite solid electrolyte (CSE) comprising LiI, PEO, and Al2O3 have been evaluated for Li battery applications. The bulk interfacial and transport properties of the CSEs seem to strongly depend on the alumina particle size. For the CSE films with 0.05 micron alumina while the bulk conductivity is around 10(exp -4) (mho/cm) at 103 C, the Li ion transport number seems to be close to unity at the same temperature. Compared to the PEO electrolyte this polymer composite electrolyte seems to exhibit robust mechanical and interfacial properties. We have studied three different films with three different alumina sizes in the range 0.01-0.3 micron. Effects of Al2O3 particle size on the electrochemical performance of polymer composite electrolyte is discussed. With TiS2 as cathode a 10 mAh small capacity cell was charged and discharged at C/40 and C/20 rates respectively.

  17. Prussian Blue Mg—Li Hybrid Batteries

    PubMed Central

    Sun, Xiaoqi; Duffort, Victor

    2016-01-01

    The major advantage of Mg batteries relies on their promise of employing an Mg metal negative electrode, which offers much higher energy density compared to graphitic carbon. However, the strong coulombic interaction of Mg2+ ions with anions leads to their sluggish diffusion in the solid state, which along with a high desolvation energy, hinders the development of positive electrode materials. To circumvent this limitation, Mg metal negative electrodes can be used in hybrid systems by coupling an Li+ insertion cathode through a dual salt electrolyte. Two “high voltage” Prussian blue analogues (average 2.3 V vs Mg/Mg2+; 3.0 V vs Li/Li+) are investigated as cathode materials and the influence of structural water is shown. Their electrochemical profiles, presenting two voltage plateaus, are explained based on the two unique Fe bonding environments. Structural water has a beneficial impact on the cell voltage. Capacities of 125 mAh g−1 are obtained at a current density of 10 mA g−1 (≈C/10), while stable performance up to 300 cycles is demonstrated at 200 mA g−1 (≈2C). The hybrid cell design is a step toward building a safe and high density energy storage system. PMID:27818909

  18. Prussian Blue Mg-Li Hybrid Batteries.

    PubMed

    Sun, Xiaoqi; Duffort, Victor; Nazar, Linda F

    2016-08-01

    The major advantage of Mg batteries relies on their promise of employing an Mg metal negative electrode, which offers much higher energy density compared to graphitic carbon. However, the strong coulombic interaction of Mg(2+) ions with anions leads to their sluggish diffusion in the solid state, which along with a high desolvation energy, hinders the development of positive electrode materials. To circumvent this limitation, Mg metal negative electrodes can be used in hybrid systems by coupling an Li(+) insertion cathode through a dual salt electrolyte. Two "high voltage" Prussian blue analogues (average 2.3 V vs Mg/Mg(2+); 3.0 V vs Li/Li(+)) are investigated as cathode materials and the influence of structural water is shown. Their electrochemical profiles, presenting two voltage plateaus, are explained based on the two unique Fe bonding environments. Structural water has a beneficial impact on the cell voltage. Capacities of 125 mAh g(-1) are obtained at a current density of 10 mA g(-1) (≈C/10), while stable performance up to 300 cycles is demonstrated at 200 mA g(-1) (≈2C). The hybrid cell design is a step toward building a safe and high density energy storage system.

  19. CuLi2Sn and Cu2LiSn: Characterization by single crystal XRD and structural discussion towards new anode materials for Li-ion batteries.

    PubMed

    Fürtauer, Siegfried; Effenberger, Herta S; Flandorfer, Hans

    2014-12-01

    The stannides CuLi2Sn (CSD-427095) and Cu2LiSn (CSD-427096) were synthesized by induction melting of the pure elements and annealing at 400 °C. The phases were reinvestigated by X-ray powder and single-crystal X-ray diffractometry. Within both crystal structures the ordered CuSn and Cu2Sn lattices form channels which host Cu and Li atoms at partly mixed occupied positions exhibiting extensive vacancies. For CuLi2Sn, the space group F-43m. was verified (structure type CuHg2Ti; a=6.295(2) Å; wR2(F²)=0.0355 for 78 unique reflections). The 4(c) and 4(d) positions are occupied by Cu atoms and Cu+Li atoms, respectively. For Cu2LiSn, the space group P63/mmc was confirmed (structure type InPt2Gd; a=4.3022(15) Å, c=7.618(3) Å; wR2(F²)=0.060 for 199 unique reflections). The Cu and Li atoms exhibit extensive disorder; they are distributed over the partly occupied positions 2(a), 2(b) and 4(e). Both phases seem to be interesting in terms of application of Cu-Sn alloys as anode materials for Li-ion batteries.

  20. CuLi2Sn and Cu2LiSn: Characterization by single crystal XRD and structural discussion towards new anode materials for Li-ion batteries

    NASA Astrophysics Data System (ADS)

    Fürtauer, Siegfried; Effenberger, Herta S.; Flandorfer, Hans

    2014-12-01

    The stannides CuLi2Sn (CSD-427095) and Cu2LiSn (CSD-427096) were synthesized by induction melting of the pure elements and annealing at 400 °C. The phases were reinvestigated by X-ray powder and single-crystal X-ray diffractometry. Within both crystal structures the ordered CuSn and Cu2Sn lattices form channels which host Cu and Li atoms at partly mixed occupied positions exhibiting extensive vacancies. For CuLi2Sn, the space group F-43m. was verified (structure type CuHg2Ti; a=6.295(2) Å; wR2(F²)=0.0355 for 78 unique reflections). The 4(c) and 4(d) positions are occupied by Cu atoms and Cu+Li atoms, respectively. For Cu2LiSn, the space group P63/mmc was confirmed (structure type InPt2Gd; a=4.3022(15) Å, c=7.618(3) Å; wR2(F²)=0.060 for 199 unique reflections). The Cu and Li atoms exhibit extensive disorder; they are distributed over the partly occupied positions 2(a), 2(b) and 4(e). Both phases seem to be interesting in terms of application of Cu-Sn alloys as anode materials for Li-ion batteries.

  1. CuLi2Sn and Cu2LiSn: Characterization by single crystal XRD and structural discussion towards new anode materials for Li-ion batteries

    PubMed Central

    Fürtauer, Siegfried; Effenberger, Herta S.; Flandorfer, Hans

    2014-01-01

    The stannides CuLi2Sn (CSD-427095) and Cu2LiSn (CSD-427096) were synthesized by induction melting of the pure elements and annealing at 400 °C. The phases were reinvestigated by X-ray powder and single-crystal X-ray diffractometry. Within both crystal structures the ordered CuSn and Cu2Sn lattices form channels which host Cu and Li atoms at partly mixed occupied positions exhibiting extensive vacancies. For CuLi2Sn, the space group F-43m. was verified (structure type CuHg2Ti; a=6.295(2) Å; wR2(F²)=0.0355 for 78 unique reflections). The 4(c) and 4(d) positions are occupied by Cu atoms and Cu+Li atoms, respectively. For Cu2LiSn, the space group P63/mmc was confirmed (structure type InPt2Gd; a=4.3022(15) Å, c=7.618(3) Å; wR2(F²)=0.060 for 199 unique reflections). The Cu and Li atoms exhibit extensive disorder; they are distributed over the partly occupied positions 2(a), 2(b) and 4(e). Both phases seem to be interesting in terms of application of Cu–Sn alloys as anode materials for Li-ion batteries. PMID:25473128

  2. Nanoparticle shapes of LiMnPO4, Li+ diffusion orientation and diffusion coefficients for high volumetric energy Li+ ion cathodes

    NASA Astrophysics Data System (ADS)

    Kwon, Nam Hee; Yin, Hui; Vavrova, Tatiana; Lim, Jonathan H.-W.; Steiner, Ullrich; Grobéty, Bernard; Fromm, Katharina M.

    2017-02-01

    Nanoparticles of LiMnPO4 were fabricated in rod, elongated as well as cubic shapes. The 1D Li+ preferred diffusion direction for each shape was determined via electron diffraction spot patterns. The shape of nano-LiMnPO4 varied the diffusion coefficient of Li+ because the Li+ diffusion direction and the path length were different. The particles with the shortest dimension along the b-axis provided the highest diffusion coefficient, resulting in the highest gravimetric capacity of 135, 100 and 60 mAh g-1 at 0.05C, 1C and 10C, respectively. Using ball-milling, a higher loading of nano-LiMnPO4 in the electrode was achieved, increasing the volumetric capacity to 263 mAh cm-3, which is ca. 3.5 times higher than the one obtained by hand-mixing of electrode materials. Thus, the electrochemical performance is governed by both the diffusion coefficient of Li+, which is dependent on the shape of LiMnPO4 nanoparticles and the secondary composite structure.

  3. Characterizing Lava Flows With LiDAR

    NASA Astrophysics Data System (ADS)

    Deligne, N. I.; Cashman, K. V.; Deardorff, N.; Dietterich, H. R.; House, P. K.; Soule, S.

    2009-12-01

    Digital elevation models (DEMs) have been used in volcanology in predictive modeling of lava flow paths, both for assessment of potential hazards and specific predictions of lava flow paths. Topographic analysis of a lava flow is potentially useful for mapping and quantifying flow surface morphologies, which in turn can be used to determine flow emplacement conditions, such as effusion rate, steadiness of flow, and interactions with pre-existing topography and surface water. However, this has been limited in application because of the coarse resolution of most DEMs. In recent years, use of Light Detection and Ranging (LiDAR) airborne laser altimetry, capable of producing high resolution (≤ 1 meter) DEMs, has become increasingly common in the geomorphic and mapping community. However, volcanologists have made little use of airborne LiDAR. Here we compare information obtained using field observations and standard (10 meter) DEMs against LiDAR high resolution DEMs to assess the usefulness, capabilities, and limitations of LiDAR as applicable to lava flows. We compare morphologic characteristics of five lava flows of different compositions, tectonic settings, flow extents, slopes, and eruption duration: (1) 1984 Mauna Loa lava flow, Hawaii; (2) December 1974 Kilauea lava flow, Hawaii; (3) c. 1600 ybp Collier Cone lava flow, central Oregon Cascades; (4) Holocene lava flows from the Sand Mountain volcanic chain, central Oregon Cascades; and (5) Pleistocene lava flows along the Owyhee River, eastern Oregon basin and range. These lava flows range in composition from basalt to andesite, and have eruption durations ranging from 6 hours (observed) to years (inferred). We measure channel width, levee and flow front heights, compression ridge amplitude, wavelength and tumuli dimensions, and surface roughness. For all but the smallest scale features, LiDAR is easily used to quantify these features, which often is impossible or technically challenging to do in the field, while

  4. Complete theoretical treatment of Dissociative Recombination of LiH^+ and LiH2^+

    NASA Astrophysics Data System (ADS)

    Haxton, Daniel; Curik, Roman; Greene, Chris

    2007-06-01

    Studies of LiH^+ and LiH2^+ ions are motivated by their role in the chemistry of the early universe. They are diatomic and triatomic prototypes of of the indirect dissociative recombination (DR) process, in which a colliding electron destroys the molecule through Rydberg capture pathways. We apply ab-initio multi-channel quantum defect theory in combination with ro-vibrational frame transformation techniques to calculate DR for these fundamental ions. Alternate versions of the vibrational frame transformation employing either Siegert states or Exterior Complex Scaling are employed. In both cases every rovibrational degree of freedom is included in the calculations, without approximation to the nuclear kinetic energy operator. In case of the LiH^+ ion we identify the underlying mechanism behind the suprisingly high DR rate recently measured in storige-ring experiments. Calculated DR rate coefficients are in a good agreement with the experimental data. This work is supported in part by the NSF.

  5. Quantum dynamics of H + LiF and Li + HF collisions at ultracold temperatures

    NASA Astrophysics Data System (ADS)

    Weck, Philippe

    2005-05-01

    The rapid progress in experimental methods such as photoassociation and Feshbach resonance methods led recently to the creation of Bose-Einstein condensates of molecules. This technical breakthrough opens new perspectives in the study of intermolecular interactions and offers new opportunites for the study of rovibrational relaxation and chemical reactivity in ultracold gases. In this work, we present quantum scattering calculations of H + LiF and Li + HF collisions at cold and ultracold temperatures for which the reactions proceed by quantum tunneling of the relatively heavy F atom through a barrier along the reaction path. Particular effort is made here to assign resonances due to the decay of metastable states of the LiFH and HLiF van der Waals complexes. The unusually deep van der Waals wells give rise to long-lived collision complexes and narrow scattering resonances in the energy dependence of reaction cross sections. The effect of vibrational excitation on the reactivity is also explored.

  6. Spectroscopic information of 6Li from elastic scattering of deuterons, 3He and 4He by 6Li

    NASA Astrophysics Data System (ADS)

    Amar, A.

    2014-07-01

    The elastic scattering of deuterons, 3He and 4He on 6Li at different incident energies have been analyzed in the framework of the optical model (OM) using ECIS88 as well as SPI GENOA codes. The optical potential parameters were extracted in the phenomenological treatment. A good agreement between theoretical and experimental differential cross-sections was obtained in whole angular range. Parameters for real part of potential have been also calculated microscopically with double-folding model for the d, 3He and 4He scattering, respectively, using DFPOT code. The elastic transfer mechanism has been studied by coupled reaction channel (CRC) method using FRESCO code. Spectroscopic amplitudes of 6Li ≡ t + 3He and 6Li ≡ α + d configurations have been extracted from d, 3He and 4He scattering on 6Li at wide energy range. A comparison between spectroscopic amplitudes obtained from deuteron and α elastically scattering from 6Li has been made. The extracted spectroscopic amplitudes of 6Li ≡ 4He + d(SF = SA2) from 6Li(d, 6Li)d and 6Li(α, 6Li)α are not the same as expected theoretically.

  7. A Stable, Magnetic, and Metallic Li3O4 Compound as a Discharge Product in a Li-Air Battery.

    PubMed

    Yang, Guochun; Wang, Yanchao; Ma, Yanming

    2014-08-07

    The Li-air battery with the specific energy exceeding that of a Li ion battery has been aimed as the next-generation battery. The improvement of the performance of the Li-air battery needs a full resolution of the actual discharge products. Li2O2 has been long recognized as the main discharge product, with which, however, there are obvious failures on the understanding of various experimental observations (e.g., magnetism, oxygen K-edge spectrum, etc.) on discharge products. There is a possibility of the existence of other Li-O compounds unknown thus far. Here, a hitherto unknown Li3O4 compound as a discharge product of the Li-air battery was predicted through first-principles swarm structure searching calculations. The new compound has a unique structure featuring the mixture of superoxide O2(-) and peroxide O2(2-), the first such example in the Li-O system. The existence of superoxide O2(-) creates magnetism and hole-doped metallicity. Findings of Li3O4 gave rise to direct explanations of the unresolved experimental magnetism, triple peaks of oxygen K-edge spectra, and the Raman peak at 1125 cm(-1) of the discharge products. Our work enables an opportunity for the performance of capacity, charge overpotential, and round-trip efficiency of the Li-air battery.

  8. Li + ion diffusion in Li 4Ti 5O 12 thin film electrode prepared by PVP sol-gel method

    NASA Astrophysics Data System (ADS)

    Rho, Young Ho; Kanamura, Kiyoshi

    2004-06-01

    Li 4Ti 5O 12 thin films for rechargeable lithium batteries were prepared by a sol-gel method with poly(vinylpyrrolidone). Interfacial properties of lithium insertion into Li 4Ti 5O 12 thin film were examined by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and potentiostatic intermittent titration technique (PITT). Redox peaks in CV were very sharp even at a fast scan rate of 50 mV s -1, indicating that Li 4Ti 5O 12 thin film had a fast electrochemical response, and that an apparent chemical diffusion coefficient of Li + ion was estimated to be 6.8×10 -11 cm 2 s -1 from a dependence of peak current on sweep rates. From EIS, it can be seen that Li + ions become more mobile at 1.55 V vs. Li/Li +, corresponding to a two-phase region, and the chemical diffusion coefficients of Li + ion ranged from 10 -10 to 10 -12 cm 2 s -1 at various potentials. The chemical diffusion coefficients of Li + ion in Li 4Ti 5O 12 were also estimated from PITT. They were in a range of 10 -11-10 -12 cm 2 s -1.

  9. Solid electrolyte interphases at Li-ion battery graphitic anodes in propylene carbonate (PC)-based electrolytes containing FEC, LiBOB, and LiDFOB as additives

    NASA Astrophysics Data System (ADS)

    Bhatt, Mahesh Datt; O'Dwyer, Colm

    2015-01-01

    Density functional theory is used to investigate the reactivity, reduction and effect of electrolyte additives such as fluoroethylene carbonate (FEC), lithium bis(oxalate) borate (LiBOB) and lithium difluoro(oxalato) borate (LiDFOB) in propylene carbonate (PC)-based Li-ion battery electrolytes. The structural, thermodynamical and calculated infra-red vibrational analyses indicate that FEC additives reduce prior to PC, providing stable SEI film formation near the graphite anode. The reduction and reaction mechanisms of LiBOB and LiDFOB influence the SEI film composition at the graphite surface. These additives contribute to stable SEI film formation without degradation of the anode structure by PC co-intercalation.

  10. Reoxidation of uranium metal immersed in a Li2O-LiCl molten salt after electrolytic reduction of uranium oxide

    NASA Astrophysics Data System (ADS)

    Choi, Eun-Young; Jeon, Min Ku; Lee, Jeong; Kim, Sung-Wook; Lee, Sang Kwon; Lee, Sung-Jai; Heo, Dong Hyun; Kang, Hyun Woo; Jeon, Sang-Chae; Hur, Jin-Mok

    2017-03-01

    We present our findings that uranium (U) metal prepared by using the electrolytic reduction process for U oxide (UO2) in a Li2O-LiCl salt can be reoxidized into UO2 through the reaction between the U metal and Li2O in LiCl. Two salt types were used for immersion of the U metal: one was the salt used for electrolytic reduction, and the other was applied to the unused LiCl salts with various concentrations of Li2O and Li metal. Our results revealed that the degree of reoxidation increases with the increasing Li2O concentration in LiCl and that the presence of the Li metal in LiCl suppresses the reoxidation of the U metal.

  11. Growth and crystal structure of LiCuO 2

    NASA Astrophysics Data System (ADS)

    Imai, Katsuhiro; Koike, Masayoshi; Sawa, Hiroshi; Takei, Humihiko

    1993-03-01

    A new crystal LiCuO2 is synthesized from Li2CuO2 using a topotactic reaction by Li extraction. X-ray measurements reveal that the crystal system of the LiCuO2 is orthorhombic, the space group is Cmmm, and the lattice parameters are a = 5.7078(6) Å, b = 9.639(2) Å, and c = 2.7172(3) Å. The crystal structure determined by Rietveld analysis is closely related to that of Li2CuO2 and of NaCuO2. Magnetic measurement of LiCuO2 shows temperature-independent paramagnetism similar to that of NaCuO2.

  12. Diffusion of 6Li in Ta and W

    NASA Astrophysics Data System (ADS)

    Vacik, J.; Hnatowicz, V.; Köster, U.; Cervena, J.; Havranek, V.; Pasold, G.

    2006-08-01

    The objective of this work was the study of 6Li diffusion in the Ta and W refractory metals. The samples were prepared by ion implantation of 380 keV 6Li+ ions into W and Ta thin foils (up to the fluence of 1016 ions/cm2) and annealed up to the temperature 1940 °C. The depth profiles of 6Li were determined using the Thermal Neutron Depth Profiling (TNDP) technique. The results showed that diffusion of 6Li in both W and Ta foils is very complex and cannot be described by simple Fick's laws. Trapping centers (in the subsurface layers of both W and Ta metals) were supposed in a trial to explain the 6Li diffusion behaviour. However, the 6Li depth profiles were only partly explained. Other aspects are necessary to take into account for more proper quantification; such as spatially dependent diffusion coefficients, etc.

  13. Phase Diagrams for the PEO-LiX Electrolyte System.

    DTIC Science & Technology

    1987-01-01

    rather flat, in sharp contrast to previous results. 3.2c PEO- LiBF4 System Pure PEO forms complexes with LiBF , and the subsequent phase diagram for...study; 0 ----NMR(15); 0 -DSC or DTA(7, 10,12); A ---a.c.conductivity(6,10,12); 4- optical microscopy(6). is 350 - (PEO) n- LiBF4 300 (PEO) n-LiCF 3SO 3...the PEO- LiBF4 system IS" , " ATOM RATIO O/Li 50 25 8 4 2 1 250 200 150 1 00 -50I 0 0 0.1 0.2 0.3 0.4 0.5 XLiPF6 -’+’ Figure 6. Phase diagram of the

  14. Li-Ion Cell Development for Low Temperature Applications

    NASA Technical Reports Server (NTRS)

    Huang, C.-K.; Sakamoto, J. S.; Surampudi, S.; Wolfenstine, J.

    2000-01-01

    JPL is involved in the development of rechargeable Li-ion cells for future Mars Exploration Missions. The specific objectives are to improve the Li-ion cell cycle life performance and rate capability at low temperature (<<-20 C) in order to enhance survivability of the Mars lander and rover batteries. Poor Li-ion rate capability at low temperature has been attributed to: (1) the electrolytes becoming viscous or freezing and/or (2) reduced electrode capacity that results from decreased Li diffusivity. Our efforts focus on increasing the rate capability at low temperature for Li-ion cells. In order to improve the rate capability we evaluated the following: (1) cathode performance at low temperatures, (2) electrode active material particle size on low temperature performance and (3) Li diffusivity at room temperature and low temperatures. In this paper, we will discuss the results of our study.

  15. Fabrication development of Li 2O pebbles by wet process

    NASA Astrophysics Data System (ADS)

    Tsuchiya, Kunihiko; Fuchinoue, Katsuhiro; Saito, Shigeru; Watarumi, Kazutoshi; Furuya, Takemi; Kawamura, Hiroshi

    1998-03-01

    Lithium oxide (Li 2O) is one of the best tritium breeding materials. A small sphere of Li 2O is proposed in some designs of fusion blankets. Recently, reprocessing technology on irradiated ceramic tritium breeders was developed from the viewpoint of effective use of resources and reduction of radioactive wastes. The wet process is advantageous for fabricating small Li 2O pebbles from the reprocessed lithium-bearing solutions. Preliminary fabrication tests of Li 2O pebbles by the wet process were carried out. However, the density of the pebbles obtained was only 55%. Therefore, process improvement tests were performed in order to increase the density of Li 2O pebbles fabricated by this method. The improved process yielded Li 2O pebbles in the target range of 80-85% T.D.

  16. Gamow shell model description of radiative capture reactions 6Li(p, γ)7Be and 6Li(n, γ)7Li

    NASA Astrophysics Data System (ADS)

    Dong, G. X.; Michel, N.; Fossez, K.; Płoszajczak, M.; Jaganathen, Y.; Betan, R. M. Id

    2017-04-01

    Background. According to standard stellar evolution, lithium abundance is believed to be a useful indicator of the stellar age. However, many evolved stars like red giants show huge fluctuations around expected theoretical abundances that are not yet fully understood. The better knowledge of nuclear reactions that contribute to the creation and destruction of lithium can help to solve this puzzle. Purpose. In this work we apply the Gamow shell model formulated in the coupled-channel representation to investigate the mirror radiative capture reactions 6Li(p, γ)7Be and 6Li(n, γ)7Li. Method. The cross-sections are calculated using a translationally invariant Hamiltonian with the finite-range interaction which is adjusted to reproduce spectra, binding energies and one-nucleon separation energies in 6–7Li, 7Be. The reaction channels are built by coupling the wave functions of ground state {1}1+ and excited states {3}1+, {0}1+, {2}1+ of 6Li with the projectile wave function in different partial waves. Results. We include all relevant E1, M1, and E2 transitions from the initial continuum states to the final bound states J=3/{2}1- and J=1/{2}- of 7Li and 7Be. Our microscopic astrophysical factor for the 6Li(p, γ)7Be reaction follows the average trend of the experimental value as a function of the center of mass energy. For {}6{Li}(n,γ ){}7{Li}, the calculated cross section agrees well with the data from the direct measurement of this reaction at stellar energies. Conclusion. We demonstrate that the s-wave radiative capture of proton (neutron) to the first excited state {J}π =1/{2}1+ of 7Be (7Li) is crucial and increases the total astrophysical S-factor by about 40%.

  17. Increasing Discharge Capacities of Li-(CF)(sub n) Cells

    NASA Technical Reports Server (NTRS)

    Whitacre, Jay; West, William

    2008-01-01

    An electrolyte additive has shown promise as a means of increasing the sustainable rates of discharge and, hence, the discharge capacities, of lithiumpoly(carbon monofluoride) electrochemical power cells. Lithium-poly(carbon monofluoride) [Li-(CF)n] cells and batteries offer very high specific energies practical values of about 600 W.h/g and a theoretical maximum value of 2,180 W.h/kg. However, because Li-(CF)n cells and batteries cannot withstand discharge at high rates, they have been relegated to niche applications that involve very low discharge currents over times of the order of hundreds to thousands of hours. Increasing the discharge capacities of Li- (CF)n batteries while maintaining high practical levels of specific energy would open new applications for these batteries. During the discharge of a Li-(CF)n cell, one of the electrochemical reactions causes LiF to precipitate at the cathode. LiF is almost completely insoluble in most non-aqueous solvents, including those used in the electrolyte solutions of Li-(CF)n cells. LiF is electrochemically inactive and can block the desired transport of ions at the cathode, and, hence, the precipitation of LiF can form an ever-thickening film on the cathode that limits the rate of discharge.

  18. Investigations of the Safety of Li/SOCl2 Batteries.

    DTIC Science & Technology

    1980-02-01

    INVESTIGATIONS OF THE SAFETY OF LI/SOCL2 BATTERIES . CU) _ SS FEB 80 K M ABRAHAM, R M MANK, 6 L HOLLECK DAABO?-78-C-0564 UNCLASSIFIED C-536 DELETTR-78...Research and Development Technical Report DELET-TR-78-054-F 0 INVESTIGATIONS OF THE SAFETY OF Li/SOC12 BATTERIES 0 Kuzhikalail M. Abraham Richard M...formed from the reaction of Li2S, produced in the cell under these operational modes, with LiAlCl4. It has been found that the lithium thioalminum

  19. Stationary Flowing Liquid Lithium (SFLiLi) systems for tokamaks

    NASA Astrophysics Data System (ADS)

    Zakharov, Leonid; Gentile, Charles; Roquemore, Lane

    2013-10-01

    The present approach to magnetic fusion which relies on high recycling plasma-wall interaction has exhausted itself at the level of TFTR, JET, JT-60 devices with no realistic path to the burning plasma. Instead, magnetic fusion needs a return to its original idea of insulation of the plasma from the wall, which was the dominant approach in the 1970s and upon implementations has a clear path to the DEMO device with PDT ~= 100 MW and Qelectric > 1 . The SFLiLi systems of this talk is the technology tool for implementation of the guiding idea of magnetic fusion. It utilizes the unique properties of flowing LiLi to pump plasma particles and, thus, insulate plasma from the walls. The necessary flow rate, ~= 1 g3/s, is very small, thus, making the use of lithium practical and consistent with safety requirements. The talk describes how chemical activity of LiLi, which is the major technology challenge of using LiLi in tokamaks, is addressed by SFLiLi systems at the level of already performed (HT-7) experiment, and in ongoing implementations for a prototype of SFLiLi for tokamak divertors and the mid-plane limiter for EAST tokamak (to be tested in the next experimental campaign). This work is supported by US DoE contract No. DE-AC02-09-CH11466.

  20. Prediction of superconductivity in Li-intercalated bilayer phosphorene

    SciTech Connect

    Huang, G. Q.; Xing, Z. W.; Xing, D. Y.

    2015-03-16

    It is shown that bilayer phosphorene can be transformed from a direct-gap semiconductor to a BCS superconductor by intercalating Li atoms. For the Li-intercalated bilayer phosphorene, we find that the electron occupation of Li-derived band is small and superconductivity is intrinsic. With increasing the intercalation of Li atoms, both increased metallicity and strong electron-phonon coupling are favorable for the enhancement of superconductivity. The obtained electron-phonon coupling λ can be larger than 1 and the superconducting temperature T{sub c} can be increased up to 16.5 K, suggesting that phosphorene may be a good candidate for a nanoscale superconductor.

  1. Properties of (Ga,Mn)As codoped with Li

    SciTech Connect

    Miyakozawa, Shohei; Chen, Lin; Matsukura, Fumihiro; Ohno, Hideo

    2014-06-02

    We grow Li codoped (Ga,Mn)As layers with nominal Mn composition up to 0.15 by molecular beam epitaxy. The layers before and after annealing are characterized by x-ray diffraction, transport, magnetization, and ferromagnetic resonance measurements. The codoping with Li reduces the lattice constant and electrical resistivity of (Ga,Mn)As after annealing. We find that (Ga,Mn)As:Li takes similar Curie temperature to that of (Ga,Mn)As, but with pronounced magnetic moments and in-plane magnetic anisotropy, indicating that the Li codoping has nontrivial effects on the magnetic properties of (Ga,Mn)As.

  2. Rechargeable LiNiO2/carbon cells

    NASA Astrophysics Data System (ADS)

    Dahn, J. R.; von Sacken, U.; Juzkow, M. W.; Al-Janaby, H.

    1991-08-01

    Rechargeable cells can be made using two different intercalation compounds, in which the chemical potential of the intercalant differs by several eV, for the electrodes. The factors that play a role in the selection of appropriate lithium intercalation compounds for such cells are discussed. For the ease of cell assembly, the cathode should be stable in air when it is fully intercalated, like LiNiO2. For the anode, the chemical potential of the intercalated Li should be close to that of Li metal, like it is in Li(x)C6. The intercalation of Li in LiNiO2 is discussed, and then in petroleum coke. Then, it is shown that LiNiO2/coke cells have high energy density, long cycle life, excellent high-temperature performance, low self-discharge rates, can be repeatedly discharged to zero volts without damage, and are easily fabricated. It is considered that this type of cell shows far more promise for widespread applications than traditional secondary Li cells using metallic Li anodes.

  3. Superconductivity in Li-doped {alpha}-rhombohedral boron

    SciTech Connect

    Nagatochi, T.; Sumiyoshi, A.; Kimura, K.; Hyodo, H.; Soga, K.; Sato, Y.; Terauchi, M.; Esaka, F.

    2011-05-01

    Metal transition and superconductivity were observed in Li-doped {alpha}-rhombohedral boron ({alpha}-B{sub 12}). The authors have established a purification method and obtained a large amount of high-purity {alpha}-B{sub 12} powder. Li doping into purified {alpha}-B{sub 12} was attempted by vapor diffusion processing (VDP) in a Mo or Ta tube. Li-doped {alpha}-B{sub 12} contained metallic glittering particles. Meissner effects were observed in such a compound with the nominal composition Li{sub x}B{sub 12} (x = 1.0, 1.4, 1.5, 1.7, or 2.5) (T{sub c} = 3.2-7 K). As for Li{sub 2.5}B{sub 12}, the temperature dependence of its electrical conductivity indicates a metallic character and its electrical resistivity drop is detected near the Meissner temperature. The existence of Li and Fermi edges in Li-doped {alpha}-B{sub 12} crystals was verified by transmission electron microscopy-electron energy loss spectroscopy (TEM-EELS). Lattice expansion, which is a well-known indicator of metal doping into a crystal, was also observed. Thus, Li doping into {alpha}-B{sub 12} was successfully achieved. Our work also suggests that it is possible to dope a larger amount of Li into {alpha}-B{sub 12} and to increase its T{sub c}.

  4. Li partitioning in the benthic foraminifera Amphistegina lessonii

    NASA Astrophysics Data System (ADS)

    Langer, Gerald; Sadekov, Aleksey; Thoms, Silke; Mewes, Antje; Nehrke, Gernot; Greaves, Mervyn; Misra, Sambuddha; Bijma, Jelle; Elderfield, Henry

    2015-12-01

    The shallow water benthic foraminifer Amphistegina lessonii was grown in seawater of variable Li and Ca concentration and shell Li/Ca was determined by means of LA-ICPMS. Shell Li/Ca is positively correlated to seawater Li/Ca only when the Li concentration of seawater is changed. If the seawater Ca concentration is changed, shell Li/Ca remains constant. This indicates that Li does not compete with Ca for incorporation in the shell of A. lessonii. A recently proposed calcification model can be applied to divalent cations (e.g., Mg and Sr), which compete for binding sites of ion transporters and positions in the calcite lattice. By contrast, the transport pathway of monovalent cations such as Li is probably diffusion based (e.g., ion-channels), and monovalent cations do not compete with Ca for a position in the calcite lattice. Here we present a new model for Li partitioning into foraminiferal calcite which predicts our experimental results and should also be applicable to other alkali metals.

  5. The Role of Lithium Passivation in LiSO2

    DTIC Science & Technology

    1986-12-29

    studied by mass spectrometry and scanning kuger spectroscopy. Abraham and Chaudhri (6) used IR and XPS techniques to study lithiu.i films from aged and...Lpeclfic conductivity of about 10-9 (ohm-cm)- 1 for the Li passivation layer. Peled (9) developed a model tc describe the film formation in the Li...the Li corrosion products precipitate to form the primary passivation layer. In analogy with the model put forth by Peled (9) for the Li/SOC1 2 couple

  6. Solvate structures and spectroscopic characterization of LiTFSI electrolytes.

    PubMed

    Seo, Daniel M; Boyle, Paul D; Sommer, Roger D; Daubert, James S; Borodin, Oleg; Henderson, Wesley A

    2014-11-26

    A Raman spectroscopic evaluation of numerous crystalline solvates with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI or LiN(SO2CF3)2) has been conducted over a wide temperature range. Four new crystalline solvate structures-(PHEN)3:LiTFSI, (2,9-DMPHEN)2:LiTFSI, (G3)1:LiTFSI and (2,6-DMPy)1/2:LiTFSI with phenanthroline, 2,9-dimethyl[1,10]phenanthroline, triglyme, and 2,6-dimethylpyridine, respectively-have been determined to aid in this study. The spectroscopic data have been correlated with varying modes of TFSI(-)···Li(+) cation coordination within the solvate structures to create an electrolyte characterization tool to facilitate the Raman band deconvolution assignments for the determination of ionic association interactions within electrolytes containing LiTFSI. It is found, however, that significant difficulties may be encountered when identifying the distributions of specific forms of TFSI(-) anion coordination present in liquid electrolyte mixtures due to the wide range of TFSI(-)···Li(+) cation interactions possible and the overlap of the corresponding spectroscopic data signatures.

  7. Structure of liquid PEO-LiTFSI electrolyte

    PubMed

    Mao; Saboungi; Price; Armand; Howells

    2000-06-12

    The structure of a polymer electrolyte, P(EO)7.5LiN(SO 2CF (3))(2), has been determined by neutron diffraction with isotropic substitution. The Li ions are bonded on average to five ether oxygens belonging to pairs of PEO coils. These are arranged with a considerable degree of extended-range order providing pathways for the Li ion conduction. The lack of ion pairing in this system below 4.8 A is reminiscent of that observed in the remarkable structure of P(EO)6LiAsF (6) and implies that anions and cations are free to migrate independently.

  8. Center problem for trigonometric Liénard systems

    NASA Astrophysics Data System (ADS)

    Gasull, Armengol; Giné, Jaume; Valls, Claudia

    2017-10-01

    We give a complete algebraic characterization of the non-degenerated centers for planar trigonometric Liénard systems. The main tools used in our proof are the classical results of Cherkas on planar analytic Liénard systems and the characterization of some subfields of the quotient field of the ring of trigonometric polynomials. Our results are also applied to some particular subfamilies of planar trigonometric Liénard systems. The results obtained are reminiscent of the ones for planar polynomial Liénard systems but the proofs are different.

  9. Probing anode degradation in automotive Li-ion batteries

    NASA Astrophysics Data System (ADS)

    Kwon, Ou Jung

    The lithium-ion battery is drawing attention as a power source for future clean and fuel-efficient vehicles. Although the Li-ion battery presently shows best performance for energy density and power density compared to other rechargeable batteries, some degradation problems still remain as key challenges for long-term durability in automotive applications. Among those problems, Li deposition is well known for causing permanent capacity loss. Fundamental mechanisms of Li deposition in the carbon anode are, however, not fully understood, especially at subzero temperature and/or under high rate charge. This dissertation introduces comprehensive study of Li deposition using automotive 18650 Li-ion cells. The mechanism and relevant diagnostic methods as well as preventive charging protocol are discussed. In part one, a new diagnostic tool is introduced utilizing 3-electrode cell system, which measures thermodynamic and kinetic parameters of cathode and anode, respectively, as a function of temperature and SOC (state of charge): open circuit potential (OCP); Li diffusion coefficient in active particles; and internal resistance. These data are employed to understand electrochemical reaction and its thermal interaction under charging conditions that result in Li deposition. Part two provides a threshold parameter for the onset of Li deposition, which is not commonly used anode potential but charge capacity, or more specifically the amount of Li+ ions participating in intercalation reaction without Li deposition at given charging circumstances. This is called the critical charge capacity in this thesis, beyond which capacity loss at normal operating condition is observed, which becomes more serious as temperature is lowered and/or charge C-rate increases. Based on these experimental results, the mechanism of Li deposition is proposed as the concept of anode particle surface saturation, meaning that once the anode particle surface is saturated with Li in any charging

  10. Photodisintegration of 7Li with progeny nuclei in excited states

    NASA Astrophysics Data System (ADS)

    Wurtz, W. A.; Pywell, R. E.; Norum, B. E.; Kucuker, S.; Sawatzky, B. D.; Weller, H. R.; Stave, S.; Ahmed, M. W.

    2015-10-01

    We study the reaction channels 7Li+γ →n +6Li (2.19 ) , 7Li+γ →n +6Li(3.56 ) , and 7Li+γ →d +5He(1.27 )→n +d +4He by detecting neutrons produced by photodisintegration events. We find absolute cross sections and angular dependence for 7Li+γ →n +6Li(2.19 ) at photon energies 13 and 15 MeV and for 7Li+γ →n +6Li+γ →d +5He(1.27 )→n +d +4He we obtain an upper bound on its cross section at photon energies 12, 13, and 15 MeV.

  11. Physical chemistry of molten-salt batteries. Final report, October 1, 1981-September 30, 1982. LiCl precipitation from LiCl-KCl anolyte in porous Li-Al electrodes

    SciTech Connect

    Vallet, C.E.; Heatherly, D.E.; Heatherly, L. Jr.; Braunstein, J.

    1983-05-01

    Composition gradients such as those predicted to occur during discharge of porous Li-Al negative electrodes of Li/S batteries with LiCl-KCl eutectic electrolyte were generated and measured in the LiCl-KCl anolyte of an electrolysis cell with Li-Al electrodes. LiCl precipitation during electrolysis was observed by two-dimensional scanning of electrolyte composition in the front part of quenched porous Li-Al anode sections using SEM/EDX. The distribution of sites of increased or decreased LiCl concentration, LiCl saturation and precipitation was mapped. Cathodic regions were observed near the cell walls. Preliminary results of analysis by Auger spectroscopy confirm LiCl precipitation in the porous anode.

  12. Synthesis and crystal structure of LiBa 2N and identification of LiBa 3N

    NASA Astrophysics Data System (ADS)

    Smetana, Volodymyr; Babizhetskyy, Volodymyr; Vajenine, Grigori V.; Simon, Arndt

    2007-06-01

    The metal-rich part of the Li sbnd Ba sbnd N system was investigated using powder and single-crystal X-ray diffraction analysis. The crystal structures of two new ternary subnitrides, LiBa 2N and of LiBa 3N, were determined from single-crystal and powder X-ray diffraction data, respectively. LiBa 2N has a tetragonal structure (space group, P4 2/nmc, Z=8, a=7.980(1), c=14.263(2) Å). The structure contains infinite mutually perpendicular rows of edge-sharing LiBa 5N octahedra. LiBa 3N is isostructural with NaBa 3N ( P6 3/mmc, Z=2, a=8.182(1), c=6.922(4) Å).

  13. Polymorphs of Li 3PO 4 and Li 2MSiO 4 (M = Mn, Co) . The role of pressure

    NASA Astrophysics Data System (ADS)

    Arroyo y de Dompablo, M. E.; Amador, U.; Gallardo-Amores, J. M.; Morán, E.; Ehrenberg, H.; Dupont, L.; Dominko, R.

    The behavior of Li 3PO 4 and Li 2MSiO 4 (M = Mn, Co) compounds under high pressure/high temperature is investigated. Pmn2 1-Li 3PO 4 remains stable up to the higher experimental limit of 80 kbar (900 °C). A sample of Li 2MnSiO 4 consisting of a mixture of Pn2 1 and Pmnb polymorphs converts upon high pressure/high temperature treatment into the Pmn2 1 polymorph; the latter being stable at 80 kbar and 900 °C. A sample of Li 2CoSiO 4- P2 1 /n transforms to the denser Pmn2 1 polymorph at 40 kbar/900 °C, but decomposes at higher pressure (60 kbar/900 °C). No evidence on any novel Li 2MSiO 4 polymorph is detected in any of the high-pressure products.

  14. The Electrical Conductivity of Li2SO4: LiBr: 0.07 K2SO4.

    DTIC Science & Technology

    1978-09-01

    compressed powder cells • Lithi um silicates and alumino silicates provide ussb1a~ con-ductivity at high temperatures (T > 400°C), but at 25°C , a c i0...of LiBr and small quantities of K2SOk . This new phase extends to the melting point of Li2 SOk :LiBr:O.07 K2 SOi , (559°C) and is thus 235° long . At

  15. First principle study of LiXS2 (X = Ga, In) as cathode materials for Li ion batteries

    NASA Astrophysics Data System (ADS)

    Feng-Ya, Rao; Fang-Hua, Ning; Li-Wei, Jiang; Xiang-Ming, Zeng; Mu-Sheng, Wu; Bo, Xu; Chu-Ying, Ouyang

    2016-02-01

    From first principle calculations, we demonstrate that LiXS2 (X = Ga, In) compounds have potential applications as cathode materials for Li ion batteries. It is shown that Li can be extracted from the LiXS2 lattice with relatively small volume change and the XS4 tetrahedron structure framework remains stable upon delithiation. The theoretical capacity and average intercalation potential of the LiGaS2 (LiInS2) cathode are 190.4 (144.2) mAh/g and 3.50 V (3.53 V). The electronic structures of the LiXS2 are insulating with band gaps of 2.88 eV and 1.99 eV for X = Ga and In, respectively. However, Li vacancies, which are formed through delithiation, change the electronic structure substantially from insulating to metallic structure, indicating that the electrical conductivities of the LiXS2 compounds should be good during cycling. Li ion migration energy barriers are also calculated, and the results show that Li ion diffusions in the LiXS2 compounds can be as good as those in the currently widely used electrode materials. Project supported by the National High Technology and Development Key Program, China (Grant No. 2015AA034201), the National Natural Science Foundation of China (Grant Nos. 11234013 and 11264014), the Natural Science Foundation of Jiangxi Province, China (Grant Nos. 20133ACB21010, 20142BAB212002, and 20132BAB212005), and the Foundation of Jiangxi Provincial Education Committee, China (Grant Nos. GJJ14254 and KJLD14024).

  16. Thermodynamic studies and the phase diagram of the Li-Mg system

    SciTech Connect

    Gasior, W.; Moser, Z.; Zakulski, W.; Schwitzgebel, G.

    1996-09-01

    By means of the electromotive force (emf) method of concentration cells of the following scheme: Li (1)/LiCl-LiF (eut) or LiCi-KCl (eut)/Li-Mg (1) or Li (1)/LiCl-LiF (eut)/Li-Mg (s). Li activities for liquid and solid alloys at the (Mg), (Li), and (Mg) + (Li) two-phase region of the Li-Mg system were determined. Liquid alloys were examined at temperatures from 638 to 889 K at various Li concentrations. The (Mg) solid solutions were investigated in two series: at constant temperatures between 773 and 876 K, with varying Li content, and at fixed Li concentrations, equal to 0.125 and 0.160 molar fractions, at different temperatures between 772 and 849 K. At the two-phase region, (Mg) + (Li), emf measurements were performed in the temperature range 773 to 838 K, with fixed Li concentrations equal to 0.20, 0.25, and 0.275 molar fractions. For (Li) solid alloys, experiments were done at temperatures 773 to 849 K for several constant Li concentrations, between 0.30 and 0.45 molar fractions, respectively. Studies on solid alloys enabled the authors also to determine the boundaries (Li)/[(Mg) + (Li)] and (Mg)/[(Mg) + (Li)] at temperatures 773 to 831 K. The resulting thermodynamic and phase boundary data of this study were used with other selected references for a critical assessment of the Li-Mg system. The Lukas BINGSS optimization program and BINFKT for the calculation of the thermodynamic functions and of the phase diagram were used. The calculated equilibrium phase diagram at temperatures below 750 K indicates a slightly lower solid solubility of Mg in (Li) in comparison with results from thermal analysis and the recently published Saunders evaluation.

  17. Thermodynamic studies and the phase diagram of the Li-Mg system

    NASA Astrophysics Data System (ADS)

    Gasior, W.; Moser, Z.; Zakulski, W.; Schwitzgebel, G.

    1996-09-01

    By means of the electromotive force (emf) method of concentration cells of the following scheme: Li (1) / LiCl-LiF (eut) or LiCi-KCl (eut) / Li-Mg (1) or Li (1) / LiCl-LiF (eut) / Li-Mg (s) Li activities for liquid and solid alloys at the (Mg), (Li), and (Mg) + (Li) two-phase region of the Li-Mg system were determined. Liquid alloys were examined at temperatures from 638 to 889 K at various Li concentrations. The (Mg) solid solutions were investigated in two series: at constant temperatures between 773 and 876 K, with varying Li content, and at fixed Li concentrations, equal to 0.125 and 0.160 molar fractions, at different temperatures between 772 and 849 K. At the two-phase region, (Mg) + (Li), emf measurements were performed in the temperature range 773 to 838 K, with fixed Li concentrations equal to 0.20, 0.25, and 0.275 molar fractions. For (Li) solid alloys, experiments were done at temperatures 773 to 849 K for several constant Li concentrations, between 0.30 to 0.45 molar fractions, respectively. Studies on solid alloys enabled us also to determine the boundaries (Li)/[(Mg) + (Li)] and (Mg)/[(Mg) + (Li)] at temperatures 773 to 831 K. The resulting thermodynamic and phase boundary data of this study were used with other selected references for a critical assessment of the Li-Mg system. The Lukas BINGSS optimization program and BINFKT for the calculation of the thermodynamic functions and of the phase diagram were used. The calculated equilibrium phase diagram at temperatures below 750 K indicates a slightly lower solid solubility of Mg in (Li) in comparison with results from thermal analysis and the recently published Saunders evaluation.

  18. Li/SO2 cells and Li/SOCl2 cells: Safe use and testing

    NASA Astrophysics Data System (ADS)

    Wagner, C. G.

    1992-05-01

    Most lithium/sulfur dioxide (Li/SO2) cells and lithium/thionyl chloride (Li/SOCl2)) cells have pressure relief safety devices called vents built into them. These vents are designed to open under conditions of increasing internal cell pressure. The likelihood of cell venting has been reduced to very low levels by optimizing cell designs. If fully developed Li/SO2 cells or Li/SOCl2 cells (or batteries) are discharged within the intended design limits, they are essentially nonhazardous. In addition, the consequences of cell ventings are being minimized by use of appropriate absorbant materials and protective coatings. During battery assembly and test, detection and monitoring equipment is used to sense the presence of vented gases. Tester data analysis techniques have been developed to foresee either an increasing likelihood of a vent or the presence of a vented cell. Standard cleanup procedures have been developed to safely decontaminate the assembly or test area following a cell vent.

  19. Measuring Li+ inventory losses in LiCoO2/graphite cells using Raman microscopy

    DOE PAGES

    Snyder, Chelsea Marie; Apblett, Christopher A.; Grillet, Anne; ...

    2016-03-25

    Here, the contribution from loss of Li+ inventory to capacity fade is described for slow rates (C/10) and long-term cycling (up to 80 cycles). It was found through electrochemical testing and ex-situ Raman analysis that at these slow rates, the entirety of capacity loss up to 80 cycles can be explained by loss of Li+ inventory in the cell. The Raman spectrum of LiCoO2 is sensitive to the state of lithiation and can therefore be leveraged to quantify the state of lithiation for individual particles. With these Raman derived estimates, the lithiation state of the cathode in the discharged statemore » is compared to electrochemical data as a function of cycle number. High correlation is found between Raman quantifications of cycleable lithium and the capacity fade. Additionally, the linear relationship between discharge capacity and cell overpotential suggests that the loss of capacity stems from an impedance rise of the electrodes, which based on Li inventory losses, is caused by SEI formation and repair.« less

  20. Radiative 8Li(n, γ)9Li Capture at Low Energies

    NASA Astrophysics Data System (ADS)

    Dubovichenko, S. B.

    2017-01-01

    Within the framework of the modified cluster model with forbidden states and classification of states according to the Young tableaux, the possibility is considered of describing the available experimental data for the total cross sections of n8Li capture at thermal and astrophysical energies.

  1. Magnetization studies and spin Hamiltonian modelling of Li2 (Li1 - xFex) N

    NASA Astrophysics Data System (ADS)

    Atkinson, James H.; Jesche, Anton; Del Barco, Enrique; Canfield, Paul C.

    2015-03-01

    The study of ferromagnetic materials has yielded many examples of compounds which exhibit large energy barriers to a reversal of magnetization and correspondingly wide magnetization versus field hysteresis loops. Some materials, such as members of the class called ``single-molecule magnets'' (SMMs), even display vivid signatures of quantum tunneling effects, manifested as step-like features in hysteresis loop measurements of crystalline ensembles. The compound Li2(Li1-xFex)N has been previously shown to display an extremely high blocking temperature (~ 20 K) and large coercive fields (>11 T), as well as step-like features like those seen in SMMs. Here we report the results of low-temperature Hall sensor magnetization studies on a crystalline sample of Li2(Li1-0.006Fe0.006)N in which we detail evidence of a preferential orientation for the observed features, as well as their dependence upon transverse component fields in their magnitude, behavior which we attempt to model with a giant spin Hamiltonian. This work is supported by the US DOE, Basic Energy Sciences under Contract No. DE-AC02-07CH11358.

  2. Thin-film Li-LiMn{sub 2}O{sub 4} batteries

    SciTech Connect

    Bates, J.B.; Lubben, D.; Dudney, N.J.

    1994-11-01

    Thin-film rechargeable Li-LiMn{sub 2}O{sub 4} batteries have been fabricated and characterized. Following deposition by electron beam evaporation of LiMn{sub 2}O{sub 4}, the amorphous as-deposited cathode films 1 cm{sup 2} in area by 0.3 to 4 {mu}m thick were annealed at 700{degree}C to 800{degree}C in oxygen in order to form the crystalline spinel phase. The capacity of the cells between 4.5 V to 3.8 V depended on the annealing conditions and ranged from 50 {mu}Ah/mg to 120 {mu}Ah/mg. When cycled over this range, the batteries exhibited excellent secondary performance with capacity losses as low as 0.001% per cycle. On charging to 5.3 V, a plateau with a median voltage of 5.1 V was observed. The total charge extracted between 3.8 V to 5.3 V corresponded to about 1Li/Mn{sub 2}O{sub 4}.

  3. Systematic Phase Diagram of LiSi and LiAl compounds from Minima Hopping Method

    NASA Astrophysics Data System (ADS)

    Romero, Aldo; Marques, Miguel; Botti, Silvana; Sarmiento-Pérez, Rafael; Valencia-Jaime, Irais; Amsler, Max; Goedecker, Stefan

    2014-03-01

    We performed an extensive theoretical exploration of the structural phase diagram of LiSi and LiAl alloys through global structural prediction. These compounds have very interesting properties. For example, LiSi alloys have been considered for high energy density anodes for future rechargeable battery technology, while LiAl alloys are expected to have applications in the field of structural components due to its light weight and maleability. The global structural prediction was performed with the minima hopping method. In this method the low energy structures are obtained by solving a set of dynamical equations of motion that allows efficient visits to local minima on the Born Oppenheimer surface. We found very good agreement between our simulations and previously reported stoichiometries. Moreover, we were able to identify several novel thermodynamically stable compositions that have not been previously synthesized. The ground-state structures were further characterized both structurally and electronically. Our calculations show that global structural prediction is a very powerful tool to predict new thermodynamically stable materials, and that it consistently outperforms other methods commonly used. Support from ACS-PRF #54075-ND10 is recognized.

  4. Radiative 8Li( n, γ)9Li Capture at Low Energies

    NASA Astrophysics Data System (ADS)

    Dubovichenko, S. B.

    2017-01-01

    Within the framework of the modified cluster model with forbidden states and classification of states according to the Young tableaux, the possibility is considered of describing the available experimental data for the total cross sections of n8Li capture at thermal and astrophysical energies.

  5. Thermal and tritium transport in Li 2O and Li 2ZrO 3

    NASA Astrophysics Data System (ADS)

    Billone, M. C.

    1996-10-01

    Lithium oxide (Li 2O) and lithium zirconate (Li 2ZrO 3) are promising tritium breeder ceramics for fusion reactors. The thermal and tritium transport databases for these materials are reviewed. Algorithms are presented for predicting the temperature and retained-tritium profiles across sintered-product and pebble-bed regions. The thermal conductivity of sintered-product material has been measured and correlated over a wide range of temperatures and densities. A modified Hall and Martin model gives good agreement with data for the effective conductivity of pebble beds of these ceramics. Laboratory data for tritium behavior in Li 2O have been used to determine model parameters in the TIARA code, which has been validated to 20 post-irradiation inventory data points. As the fundamental database for Li 2ZrO 3 is less complete, a residency-time correlation, based on 31 inventory data points, is proposed. The two ceramics are compared in the context of an ITER breeding-blanket design.

  6. Primordial Li abundance and massive particles

    SciTech Connect

    Latin-Capital-Letter-Eth apo, H.

    2012-10-20

    The problem of the observed lithium abundance coming from the Big Bang Nucleosynthesis is as of yet unsolved. One of the proposed solutions is including relic massive particles into the Big Bang Nucleosynthesis. We investigated the effects of such particles on {sup 4}HeX{sup -}+{sup 2}H{yields}{sup 6}Li+X{sup -}, where the X{sup -} is the negatively charged massive particle. We demonstrate the dominance of long-range part of the potential on the cross-section.

  7. Li-Ion Battery for ISS

    NASA Technical Reports Server (NTRS)

    Dalton, Penni; Cohen, Fred

    2004-01-01

    The ISS currently uses Ni-H2 batteries in the main power system. Although Ni-H2 is a robust and reliable system, recent advances in battery technology have paved the way for future replacement batteries to be constructed using Li-ion technology. This technology will provide lower launch weight as well as increase ISS electric power system (EPS) efficiency. The result of incorporating this technology in future re-support hardware will be greater power availability and reduced program cost. the presentations of incorporating the new technology.

  8. Anionic States of LiFLi

    DTIC Science & Technology

    1994-04-22

    EUIYCASFCTO 9 SECURITT12b CLSIIAIONT0.RIMITTION CODE TRC UNIDCLASIFEDT HCAS SIFIAPRO ED UNCPBICR LEASSEFIEDUNITE SALE IT.OO.0S50 DItTRdarIO Ior UNLIMITED-89 13...core Is atomic orbitals were doubly occupied in every configuration state function (CSF). The neglected core-core and core- valence correlation...has 2s and 2p valence orbitals to use but H has only Is valence orbitals. B. The Anion The ground electronic state of LiFLi- has a linear equilibrium

  9. Li-ion EMU Battery Testing

    NASA Technical Reports Server (NTRS)

    Rehm, Raymond; Bragg, Bobby; Strangways, Brad

    2001-01-01

    A 45Ah Lithium ion (Li-Ion) battery comprised of 5 Yardney prismatic cells was evaluated to replace the silver-zinc cells in the Extra-vehicular Mobility Unit (EMU). Tests determined that the five cell battery can meet the mission objective of 500 duty cycles and maintain a minimum voltage of 16.0 V without an individual cell voltage dropping below 3.0V. Forty real time cycles were conducted to develop BOL trend data. Decision to switch to accelerated cycling for the remaining 460 cycles was made since Real Time cycling requires 1 day/cycle. Conclusions indicate that battery replacement would indeed be prudent.

  10. Ab initio calculation of 7Li photodisintegration

    NASA Astrophysics Data System (ADS)

    Bacca, Sonia; Arenhövel, Hartmuth; Barnea, Nir; Leidemann, Winfried; Orlandini, Giuseppina

    2004-12-01

    The 7Li total photoabsorption cross section is calculated microscopically, using the semi-realistic AV4' nucleon-nucleon potential. The interaction of the final 7-nucleon system is fully taken into account via the Lorentz integral transform (LIT) method. For the calculation of the LIT we use expansions in hyperspherical harmonics (HH) in conjunction with the HH effective interaction (EIHH) approach. The convergence of the LIT expansion is discussed in detail. The calculated cross section agrees quite well with the available experimental data, which cover an energy range from threshold up to 100 MeV.

  11. Reversible superconductor-insulator transition in LiTi2O4 induced by Li-ion electrochemical reaction.

    PubMed

    Yoshimatsu, K; Niwa, M; Mashiko, H; Oshima, T; Ohtomo, A

    2015-11-06

    Transition metal oxides display various electronic and magnetic phases such as high-temperature superconductivity. Controlling such exotic properties by applying an external field is one of the biggest continuous challenges in condensed matter physics. Here, we demonstrate clear superconductor-insulator transition of LiTi2O4 films induced by Li-ion electrochemical reaction. A compact electrochemical cell of pseudo-Li-ion battery structure is formed with a superconducting LiTi2O4 film as an anode. Li content in the film is controlled by applying a constant redox voltage. An insulating state is achieved by Li-ion intercalation to the superconducting film by applying reduction potential. In contrast, the superconducting state is reproduced by applying oxidation potential to the Li-ion intercalated film. Moreover, superconducting transition temperature is also recovered after a number of cycles of Li-ion electrochemical reactions. This complete reversible transition originates in difference in potentials required for deintercalation of initially contained and electrochemically intercalated Li(+) ions.

  12. An atomic beam of 6Li — 7Li for high resolution spectroscopy from matrix isolation sublimation

    NASA Astrophysics Data System (ADS)

    Oliveira, A. N.; Sacramento, R. L.; Silva, B. A.; Uhlmann, F. O.; Wolff, W.; Cesar, C. L.

    2016-07-01

    We propose the Matrix Isolation Sublimation (MlSu) technique for generating cold lithium atoms for the measurement of the 6Li - 7Li isotope shift in D1 and D2 transitions. The technique is capable of generating cold 6Li and 7Li beams at 4 K with forward velocity of 125 m/s. Using this beam we offer a distinguished source of lithium atoms for transitions measurements, adding a new possibility to make high resolution spectroscopy towards improving the experimental checks of the theory.

  13. Impedance behavior of the LiMn2O4/LiPF6-DMC-EC interface during cycling

    SciTech Connect

    Striebel, Kathryn A.; Sakai, Eiji; Cairns, Elton J.

    2000-12-19

    Room temperature impedance measurements of the LiMn2O4/LiPF6-EC-DMC interface have been used to identify a previously unreported step in the formation of the SEI layer on this cathode. The low frequency impedance and potential of pure dense LiMn2O4 films was found to depend logarithmically on time in the end-of-discharge (EOD) state. The rate of the impedance rise decreased with Mn3+ content. The increased impedance was removed by oxidation of the film to 4.5 V vs. Li/Li+. The observations are consistent with a reversible disproportionation of part of the LiMn2O4 into Li2Mn2O4 and l-Mn2O4. Analyses of cyclic voltammograms and impedance spectra at intervals during constant current cycling of the LiMn2O4 films suggest that Li2Mn2O4 on the surface also plays a major role in the capacity fade.

  14. Li-Ion Dynamics in Li5+xLa3ZrxNb2-xO12

    NASA Astrophysics Data System (ADS)

    Nozaki, Hiroshi; Ohta, Shingo; Harada, Masashi; Månsson, Martin; Sheptyakov, Denis; Pomjakushin, Vladimir; Watanabe, Isao; Ikedo, Yutaka; Miyake, Yasuhiro; Sugiyama, Jun

    A diffusive behavior of Li+ ion in a garnet-type oxide, Li5+xLa3ZrxNb2-xO12 with x = 0-2, has been investigated by both a positive muon-spin relaxation (µ+SR) and quasi-elastic neutron scattering (QENS) technique using powder samples. The µ+SR results revealed that Li+ ions start to diffuse above ~150 K for the whole samples measured. The activation energy of Li diffusion (Ea) estimated from the µ+SR data was in good agreement with Ea obtained by the QENS measurements. However, both Eas were about a half of Ea of ionic conductivity of Li+ (σLi), which was evaluated by AC-impedance measurements on sintered pellets. This indicated the serious effect of grain boundary and/or surface on Ea. Furthermore, since the self-diffusion coefficient of Li+ estimated by µ+SR is roughly independent of x, the number of mobile Li+ in the garnet lattice was found to be the predominant parameter to determine σLi.

  15. Predicted Structure, Thermo-Mechanical Properties and Li Ion Transport in LiAlF4 Glass

    SciTech Connect

    Stechert, T. R.; Rushton, M. J. D.; Grimes, R. W.; Dillon, A. C.

    2012-08-15

    Materials with the LiAlF{sub 4} composition are of interest as protective electrode coatings in Li ion battery applications due to their high cationic conductivity. Here classical molecular dynamics calculations are used to produce amorphous model structures by simulating a quench from the molten state. These are analysed in terms of their individual pair correlation functions and atomic coordination environments. This indicates that amorphous LiAlF{sub 4} is formed of a network of corner sharing AlF{sub 6} octahedra. Li ions are distributed within this network, primarily associated with non-bridging fluorine atoms. The nature of the octahedral network is further analysed through intra- and interpolyhedral bond angle distributions and the relative populations of bridging and non-bridging fluorine ions are calculated. Network topology is considered through the use of ring statistics, which indicates that, although topologically well connected, LiAlF{sub 4} contains an appreciable number of corner-linked branch-like AlF{sub 6} chains. Thermal expansion values are determined above and below the predicted glass transition temperature of 1340 K. Finally, movement of Li ions within the network is examined with predictions of the mean squared displacements, diffusion coefficients and Li ion activation energy. Different regimes for lithium ion movement are identified, with both diffusive and sessile Li ions observed. For migrating ions, a typical trajectory is illustrated and discussed in terms of a hopping mechanism for Li transport.

  16. Li2CuVO4: A high capacity positive electrode material for Li-ion batteries

    NASA Astrophysics Data System (ADS)

    Ben Yahia, Hamdi; Shikano, Masahiro; Yamaguchi, Yoichi

    2016-07-01

    The new compound Li2CuVO4 was synthesized by a solid state reaction route, and its crystal structure was determined from single crystal X-ray diffraction data. Li2CuVO4 was characterized by galvanometric cycling, cycle voltammetry, and electrochemical impedance spectroscopy. The structure of Li2CuVO4 is isotypic to Pmn21-Li3VO4. It can be described as a disordered wurtzite structure with rows of Li1/Cu1 atoms alternating with rows of (Li2/Cu2)-V-(Li2/Cu2) atoms along [100]. All cations are tetrahedrally coordinated. The lithium and copper atoms are statistically disordered over two crystallographic sites. The electrochemical cycling between 2.0 and 4.7 V indicates that almost two lithium atoms could be extracted and re-intercalated. This delivers a maximum discharge capacity of 257 mA h g-1 at a C/50 rate (theoretical capacity = 139 mA h g-1 for one lithium). Li2CuVO4 shows also high rate capability with a capacity of 175 mA h g-1 at 1C rate. This demonstrates that Cu-based compounds can be very interesting as electrodes for Li-ion batteries if Cu-dissolution is avoided.

  17. Residual stresses and clamped thermal expansion in LiNbO3 and LiTaO3 thin films

    NASA Astrophysics Data System (ADS)

    Bartasyte, A.; Plausinaitiene, V.; Abrutis, A.; Murauskas, T.; Boulet, P.; Margueron, S.; Gleize, J.; Robert, S.; Kubilius, V.; Saltyte, Z.

    2012-09-01

    Residual stresses in LiNbO3 and LiTaO3 epitaxial thin films were evaluated taking into account Li nonstoichiometry by means of Raman spectroscopy and x-ray diffraction. The epitaxial films were grown on C-cut sapphire substrates by pulsed injection metal organic chemical vapour deposition. Clamping of the epitaxial films by the substrate induced a transfer from the in plane thermal expansion to the out of plane component. The temperature of the phase transition of clamped LiTaO3 films was close to that expected for a bulk sample.

  18. Electrodeposition of Mg-Li-Al-La Alloys on Inert Cathode in Molten LiCl-KCl Eutectic Salt

    NASA Astrophysics Data System (ADS)

    Han, Wei; Chen, Qiong; Sun, Yi; Jiang, Tao; Zhang, Milin

    2011-12-01

    Electrochemical preparation of Mg-Li-Al-La alloys on inert electrodes was investigated in LiCl-KCl melt at 853 K (580 °C). Cyclic voltammograms (CVs) and square wave voltammograms (SWVs) show that the existence of AlCl3 or AlF3 could promote La deposition on an active Al substrate, which is predeposited on inert electrodes. All electrochemical tests show that the reduction of La3+ is a one-step reduction process with three electrons exchanged. The reduction of La(III)→La(0) occurred at -2.04 V, and the underpotential deposition (UPD) of La was detected at -1.55 V ( vs Ag/AgCl). The same phenomena concerning La UPD were observed on two inert cathodes, W and Mo. In addition, Mg-Li-Al-La alloys were obtained by galvanostatic electrolysis on the W cathode from La2O3 in LiCl-KCl-MgCl2-KF melts with aluminum as the anode. X-ray diffraction (XRD) measurements indicated that various phases like the Al2La, Al12Mg17, and βLi phase (LiMg/Li3Mg7) existed in the Mg-Li-Al-La alloys. The distribution of Mg, Al, and La in Mg-Li-Al-La alloys from the analysis of a scan electron micrograph (SEM) and energy dispersive spectrometry (EDS) indicated that the elements Mg, Al, and La distributed homogeneously in the alloys.

  19. Exploration of spinel LiCrTiO4 as the cathode material for rechargeable Mg-Li hybrid batteries.

    PubMed

    Yao, Ye; Zhang, Lu; Bie, Xiaofei; Chen, Hong; Wang, Chunzhong; Du, Fei; Chen, Gang

    2017-06-17

    Mg-Li hybrid batteries have attracted wide interest in recent years because of the potential safety as well as the cost benefit and high volumetric capacity. However, the slow kinetic properties strongly hinder their commercial application. In this study, we prepare spinel LiCrTiO4 by the solid-state reaction and conduct a comprehensive study on the improvement of its performance in Mg-Li hybrid batteries by optimizing the dual-salt electrolytes. It is found that LiCrTiO4 shows the reversible discharge/charge capacity of 178/169 mAh g-1 in the electrolyte of 1 M LiCl and 0.3 M APC (all-phenyl-complex). And when the concentration of APC increases to 0.4 M, LiCrTiO4 shows a high capacity retention of 95% after 30 cycles. In addition, no phase transition could be observed for the LiCrTiO4 electrode in dual-salts system, suggesting a highly electrochemical reversibility. Ex-situ EDX and SEM indicates that only Li+ ions are inserted into the cathode side, while Mg2+ ions reversibly deposit on the surface of Mg metal with no dendrite-like growth, indicative of good safety of Mg-Li hybrid batteries. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Reversible superconductor-insulator transition in LiTi2O4 induced by Li-ion electrochemical reaction

    PubMed Central

    Yoshimatsu, K.; Niwa, M.; Mashiko, H.; Oshima, T.; Ohtomo, A.

    2015-01-01

    Transition metal oxides display various electronic and magnetic phases such as high-temperature superconductivity. Controlling such exotic properties by applying an external field is one of the biggest continuous challenges in condensed matter physics. Here, we demonstrate clear superconductor-insulator transition of LiTi2O4 films induced by Li-ion electrochemical reaction. A compact electrochemical cell of pseudo-Li-ion battery structure is formed with a superconducting LiTi2O4 film as an anode. Li content in the film is controlled by applying a constant redox voltage. An insulating state is achieved by Li-ion intercalation to the superconducting film by applying reduction potential. In contrast, the superconducting state is reproduced by applying oxidation potential to the Li-ion intercalated film. Moreover, superconducting transition temperature is also recovered after a number of cycles of Li-ion electrochemical reactions. This complete reversible transition originates in difference in potentials required for deintercalation of initially contained and electrochemically intercalated Li+ ions. PMID:26541508

  1. Coulomb dissociation and momentum distributions for [sup 11]Li [yields] [sup 9]Li + n + n breakup reactions

    SciTech Connect

    Esbensen, H.

    1993-01-01

    Momentum distributions for the [sup 11]Li [yields] [sup 9]Li+n+n breakup reaction, generated by Coulomb dipole excitations, axe calculated in a 3-body model for [sup 11]Li. The relative momentum distribution of the two neutrons is in good agreement with recent 3-body coincidence measurements but the momentum distribution for the [sup 9]Li recoil and the decay energy spectrum are much narrower than observed. These discrepancies may be due to higher order dynamical effects which have been ignored.

  2. Coulomb dissociation and momentum distributions for {sup 11}Li {yields} {sup 9}Li + n + n breakup reactions

    SciTech Connect

    Esbensen, H.

    1993-03-01

    Momentum distributions for the {sup 11}Li {yields} {sup 9}Li+n+n breakup reaction, generated by Coulomb dipole excitations, axe calculated in a 3-body model for {sup 11}Li. The relative momentum distribution of the two neutrons is in good agreement with recent 3-body coincidence measurements but the momentum distribution for the {sup 9}Li recoil and the decay energy spectrum are much narrower than observed. These discrepancies may be due to higher order dynamical effects which have been ignored.

  3. Li3-O-Li3 molecule: a metal-nonmetal-metal sandwichlike compound with a distending electron cloud.

    PubMed

    Chen, Wei; Li, Zhi-Ru; Wu, Di; Li, Ying; Sun, Chia-Chung

    2005-10-22

    The D3d and D2d isomers of the Li3-O-Li3 molecule are metal-nonmetal-metal sandwichlike structures that contain two Li3 superalkali atoms. Their geometries and the real frequencies are obtained at the CCSD(T)/aug-cc-pVDZ level. They are different from the traditional types of the nonmetal-metal-nonmetal sandwich compounds. The natural bond orbital calculation and the topological property nabla2rho(r) calculation indicate that they are typical ionic compounds. In two isomers, the O2- anion is sandwiched in between two Li3+ cation rings. However, the different orientations of two Li3+ planes give the D3d isomer its own special characteristics. Under the action of the O2- anion in the center, the valence electrons of the D3d isomer are pushed out from two Li3+ triangle rings. This special interaction causes three phenomena. First, the valence electron clouds are distended. Second, the vertical ionization energy of the D3d isomer is considerably low, 4.39 eV, so that it may also be viewed as a superalkali atom. Third, we find that the D3d isomer owns the out-of-plane aromaticity and the largest negative nucleus-independent chemical shift value (-10.8 ppm) exists at 2.5 A above the center of the Li3+ ring, not at the center of the Li3+ ring like the isolated aromatic Li3+ cation.

  4. Electrochemical behavior of nanostructured LiV3O8 in aqueous LiNO3 solution

    NASA Astrophysics Data System (ADS)

    Liu, Li; Tian, Fanghua; Yang, Zhenhua; Wang, Xingyan; Zhou, Meng; Wang, Xianyou

    2011-12-01

    Despite the large number of studies on the electrochemical behavior of LiV3O8 as a cathode material in nonaqueous lithium ion batteries, little information is available about the electrochemical behavior of LiV3O8 as an anode material in aqueous rechargeable lithium batteries. In this work, nanostructured LiV3O8 is successfully prepared using a low-temperature solid-state method. The electrochemical properties of the LiV3O8 electrode in 1 M, 5 M, and saturated LiNO3 aqueous electrolytes have been characterized by cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge/discharge experiments. The results show that LiV3O8 electrode in saturated LiNO3 electrolyte exhibits good electrochemical performance in terms of specific capacity and electrochemical cycling performance. LiV3O8 electrode can be reversibly cycled in saturated LiNO3 aqueous electrolyte for 300 cycles at a rate of 0.5 C (300 mA g-1 is assumed to be 1 C rate) with impressive specific capacities.

  5. Quantitation of Li2O2 stored in Li-O2 batteries based on its reaction with an oxoammonium salt.

    PubMed

    Hase, Yoko; Ito, Emi; Shiga, Tohru; Mizuno, Fuminori; Nishikoori, Hidetaka; Iba, Hideki; Takechi, Kensuke

    2013-09-28

    Precise knowledge of the discharge and charge reactions within Li-O2 batteries is an important aspect of developing highly efficient, rechargeable Li-O2 cells. We describe an analytical method capable of determining the quantity of Li2O2 in the cathode on the basis of the reaction of Li2O2 with an oxoammonium salt.

  6. Crystal structure and magnetic properties of Li,Cr-containing molybdates Li 3Cr(MoO 4) 3, LiCr(MoO 4) 2 and Li 1.8Cr 1.2(MoO 4) 3

    NASA Astrophysics Data System (ADS)

    Sarapulova, A.; Mikhailova, D.; Senyshyn, A.; Ehrenberg, H.

    2009-12-01

    Single crystals of LiCr(MoO 4) 2, Li 3Cr(MoO 4) 3 and Li 1.8Cr 1.2(MoO 4) 3 were grown by a flux method during the phase study of the Li 2MoO 4-Cr 2(MoO 4) 3 system at 1023 K. LiCr(MoO 4) 2 and Li 3Cr(MoO 4) 3 single phases were synthesized by solid-state reactions. Li 3Cr(MoO 4) 3 adopts the same structure type as Li 3In(MoO 4) 3 despite the difference in ionic radii of Cr 3+ and In 3+ for octahedral coordination. Li 3Cr(MoO 4) 3 is paramagnetic down to 7 K and shows a weak ferromagnetic component below this temperature. LiCr(MoO 4) 2 is isostructural with LiAl(MoO 4) 2 and orders antiferromagnetically below 20 K. The magnetic structure of LiCr(MoO 4) 2 was determined from low-temperature neutron diffraction and is based on the propagation vektor k⇒=({1}/{2},{1}/{2},0). The ordered magnetic moments were refined to 2.3(1) μ B per Cr-ion with an easy axis close to the [1 1 1¯] direction. A magnetic moment of 4.37(3) μ B per Cr-ion was calculated from the Curie constant for the paramagnetic region. The crystal structures of the hitherto unknown Li 1.8Cr 1.2(MoO 4) 3 and LiCr(MoO 4) 2 are compared and reveal a high degree of similarity: In both structures MoO 4-tetrahedra are isolated from each other and connected with CrO 6 and LiO 5 via corners. In both modifications there are Cr 2O 10 fragments of edge-sharing CrO 6-octahedra.

  7. Selected test results from the LiFeBatt iron phosphate Li-ion battery.

    SciTech Connect

    Ingersoll, David T.; Hund, Thomas D.

    2008-09-01

    In this paper the performance of the LiFeBatt Li-ion cell was measured using a number of tests including capacity measurements, capacity as a function of temperature, ohmic resistance, spectral impedance, high power partial state of charge (PSOC) pulsed cycling, pulse power measurements, and an over-charge/voltage abuse test. The goal of this work was to evaluate the performance of the iron phosphate Li-ion battery technology for utility applications requiring frequent charges and discharges, such as voltage support, frequency regulation, and wind farm energy smoothing. Test results have indicated that the LiFeBatt battery technology can function up to a 10C{sub 1} discharge rate with minimal energy loss compared to the 1 h discharge rate (1C). The utility PSOC cycle test at up to the 4C{sub 1} pulse rate completed 8,394 PSOC pulsed cycles with a gradual loss in capacity of 10 to 15% depending on how the capacity loss is calculated. The majority of the capacity loss occurred during the initial 2,000 cycles, so it is projected that the LiFeBatt should PSOC cycle well beyond 8,394 cycles with less than 20% capacity loss. The DC ohmic resistance and AC spectral impedance measurements also indicate that there were only very small changes after cycling. Finally, at a 1C charge rate, the over charge/voltage abuse test resulted in the cell venting electrolyte at 110 C after 30 minutes and then open-circuiting at 120 C with no sparks, fire, or voltage across the cell.

  8. Femtosecond Cr:LiSAF and Cr:LiCAF lasers pumped by tapered diode lasers.

    PubMed

    Demirbas, Umit; Schmalz, Michael; Sumpf, Bernd; Erbert, Götz; Petrich, Gale S; Kolodziejski, Leslie A; Fujimoto, James G; Kärtner, Franz X; Leitenstorfer, Alfred

    2011-10-10

    We report compact, low-cost and efficient Cr:Colquiriite lasers that are pumped by high brightness tapered laser diodes. The tapered laser diodes provided 1 to 1.2 W of output power around 675 nm, at an electrical-to-optical conversion efficiency of about 30%. Using a single tapered diode laser as the pump source, we have demonstrated output powers of 500 mW and 410 mW together with slope efficiencies of 47% and 41% from continuous wave (cw) Cr:LiSAF and Cr:LiCAF lasers, respectively. In cw mode-locked operation, sub-100-fs pulse trains with average power between 200 mW and 250 mW were obtained at repetition rates around 100 MHz. Upon pumping the Cr:Colquiriite lasers with two tapered laser diodes (one from each side of the crystal), we have observed scaling of cw powers to 850 mW in Cr:LiSAF and to 650 mW in Cr:LiCAF. From the double side pumped Cr:LiCAF laser, we have also obtained ~220 fs long pulses with 5.4 nJ of pulse energy at 77 MHz repetition rate. These are the highest energy levels reported from Cr:Colquiriite so far at these repetition rates. Our findings indicate that tapered diodes in the red spectral region are likely to become the standard pump source for Cr:Colquiriite lasers in the near future. Moreover, the simplified pumping scheme might facilitate efficient commercialization of Cr:Colquiriite systems, bearing the potential to significantly boost applications of cw and femtosecond lasers in this spectral region (750-1000 nm).

  9. Fast neutron measurements with 7Li and 6Li enriched CLYC scintillators

    NASA Astrophysics Data System (ADS)

    Giaz, A.; Blasi, N.; Boiano, C.; Brambilla, S.; Camera, F.; Cattadori, C.; Ceruti, S.; Gramegna, F.; Marchi, T.; Mattei, I.; Mentana, A.; Million, B.; Pellegri, L.; Rebai, M.; Riboldi, S.; Salamida, F.; Tardocchi, M.

    2016-07-01

    The recently developed Cs2LiYCl6:Ce (CLYC) crystals are interesting scintillation detectors not only for their gamma energy resolution (<5% at 662 keV) but also for their capability to identify and measure the energy of both gamma rays and fast/thermal neutrons. The thermal neutrons were detected by the 6Li(n,α)t reaction while for the fast neutrons the 35Cl(n,p)35S and 35Cl(n,α)32P neutron-capture reactions were exploited. The energy of the outgoing proton or α particle scales linearly with the incident neutron energy. The kinetic energy of the fast neutrons can be measured using both the Time Of Flight (TOF) technique and using the CLYC energy signal. In this work, the response to monochromatic fast neutrons (1.9-3.8 MeV) of two CLYC 1″×1″ crystals was measured using both the TOF and the energy signal. The observables were combined to identify fast neutrons, to subtract the thermal neutron background and to identify different fast neutron-capture reactions on 35Cl, in other words to understand if the detected particle is an α or a proton. We performed a dedicated measurement at the CN accelerator facility of the INFN Legnaro National Laboratories (Italy), where the fast neutrons were produced by impinging a proton beam (4.5, 5.0 and 5.5 MeV) on a 7LiF target. We tested a CLYC detector 6Li-enriched at about 95%, which is ideal for thermal neutron measurements, in parallel with another CLYC detector 7Li-enriched at more than 99%, which is suitable for fast neutron measurements.

  10. Density functional theory study of lithium diffusion at the interface between olivine-type LiFePO4 and LiMnPO4

    NASA Astrophysics Data System (ADS)

    Shi, Jianjian; Wang, Zhiguo; Qing Fu, Yong

    2016-12-01

    Coating LiMnPO4 with a thin layer of LiFePO4 shows a better electrochemical performance than the pure LiFePO4 and LiMnPO4, thus it is critical to understand Li diffusion at their interfaces to improve the performance of electrode materials. Li diffusion at the (1 0 0)\\text{LiFeP{{\\text{O}}4}} //(1 0 0)\\text{LiMnP{{\\text{O}}4}} , (0 1 0)\\text{LiFeP{{\\text{O}}4}} //(0 1 0)\\text{LiMnP{{\\text{O}}4}} , and (0 0 1)\\text{LiFeP{{\\text{O}}4}} //(0 0 1)\\text{LiMnP{{\\text{O}}4}} interfaces between LiFePO4 and LiMnPO4 was investigated using density functional theory. The calculated diffusion energy barriers are 0.55 eV for Li to diffuse along the (0 0 1) interface, 0.44 and 0.49 eV for the Li diffusion inside the LiMnPO4 and along the (1 0 0) interface, respectively. When Li diffuses from the LiFePO4 to LiMnPO4 by passing through the (0 1 0) interfaces, the diffusion barriers are 0.45 and 0.60 eV for the Li diffusions in both sides. The diffusion barriers for Li to diffuse in LiMnPO4 near the interfaces decrease compared with those in the pure LiMnPO4. The calculated diffusion coefficient of Li along the (1 0 0) interface is in the range of 3.65  ×  10-11-5.28  ×  10-12 cm2 s-1, which is larger than that in the pure LiMnPO4 with a value of 7.5  ×  10-14 cm2 s-1. Therefore, the charging/discharging rate performance of the LiMnPO4 can be improved by surface coating with the LiFePO4.

  11. Recognizing Excellence: Pinging--Sound at Work

    ERIC Educational Resources Information Center

    Lindquist, William; Forsberg, Britt

    2014-01-01

    One author shares the unique opportunity to be immersed in the science of "sound at work" through participation in NOAA's (National Oceanic and Atmospheric Administration) Teacher at Sea Program. A third- through fifth-grade learning outcome within the Nature of Science section of the "Next Generation Science Standards"…

  12. An Atmospheric Pressure Ping-Pong "Ballometer"

    ERIC Educational Resources Information Center

    Kazachkov, Alexander; Kryuchkov, Dmitriy; Willis, Courtney; Moore, John C.

    2006-01-01

    Classroom experiments on atmospheric pressure focus largely on demonstrating its existence, often in a most impressive way. A series of amusing physics demonstrations is widely known and practiced by educators teaching the topic. However, measuring the value of atmospheric pressure(P[subscript atm]) is generally done in a rather mundane way,…

  13. An Atmospheric Pressure Ping-Pong "Ballometer"

    ERIC Educational Resources Information Center

    Kazachkov, Alexander; Kryuchkov, Dmitriy; Willis, Courtney; Moore, John C.

    2006-01-01

    Classroom experiments on atmospheric pressure focus largely on demonstrating its existence, often in a most impressive way. A series of amusing physics demonstrations is widely known and practiced by educators teaching the topic. However, measuring the value of atmospheric pressure(P[subscript atm]) is generally done in a rather mundane way,…

  14. Recognizing Excellence: Pinging--Sound at Work

    ERIC Educational Resources Information Center

    Lindquist, William; Forsberg, Britt

    2014-01-01

    One author shares the unique opportunity to be immersed in the science of "sound at work" through participation in NOAA's (National Oceanic and Atmospheric Administration) Teacher at Sea Program. A third- through fifth-grade learning outcome within the Nature of Science section of the "Next Generation Science Standards"…

  15. Stable Li Plating/Stripping Electrochemistry Realized by a Hybrid Li Reservoir in Spherical Carbon Granules with 3D Conducting Skeletons.

    PubMed

    Ye, Huan; Xin, Sen; Yin, Ya-Xia; Li, Jin-Yi; Guo, Yu-Guo; Wan, Li-Jun

    2017-04-14

    Lithium metal is a promising battery anode. However, inhomogeneous mass and charge transfers across the Li/electrolyte interface result in formation of dendritic Li and "dead" Li, and an unstable solid electrolyte interphase, which incur serious problems to impede its service in rechargeable batteries. Here, we show that the above problems can be mitigated by regulating the interfacial mass/charge transfer. The key to our strategy is hybrid Li storage in onion-like, graphitized spherical C granules wired on a three-dimensional conducting skeleton, which enhances the negativity of surface charge of the C host to contribute to a uniform Li plating while also forming stable Li/C intercalation compounds to offset any irreversible Li loss during cycling. As a result, the anode shows a suppressed dendrite formation and a high Li utilization >95%, enabling a practical Li battery to strike a long lifespan of 1000 cycles at a surplus Li of merely 5%.

  16. Li3PO4-added garnet-type Li6.5La3Zr1.5Ta0.5O12 for Li-dendrite suppression

    NASA Astrophysics Data System (ADS)

    Xu, Biyi; Li, Wenlong; Duan, Huanan; Wang, Haojing; Guo, Yiping; Li, Hua; Liu, Hezhou

    2017-06-01

    This paper proposes a strategy to stabilize the garnet/Li interface by introducing Li3PO4 as an additive in garnet-type Li6.5La3Zr1.5Ta0.5O12. The Li3PO4-added Li6.5La3Zr1.5Ta0.5O12 electrolyte exhibits a room-temperature Li-ion conductivity of 1.4 × 10-4 S cm-1, which is less than that of the Li3PO4-free counterparts (4.6 × 10-4 S cm-1). However, the presence of Li3PO4 improves the interfacial compatibility and suppresses Li-dendrite formation during Li-metal plating/stripping. The symmetric Li/garnet/Li cells with Li3PO4-added Li6.5La3Zr1.5Ta0.5O12 have been successfully cycled at a current density of 0.1 mA cm-2 at 60 °C for 60 h; on contrast, the control cells with Li3PO4-free Li6.5La3Zr1.5Ta0.5O12 display noisy potential with large voltage polarization and get short-circuited completely after 33-h cycling under the same operating condition. The outstanding interface stability can be attributed to the in situ reaction of the Li flux with Li3PO4 to form a self-limiting and ion-conducting interphase, Li3P, which is confirmed experimentally.

  17. Electrocatalysis in Li-S batteries

    NASA Astrophysics Data System (ADS)

    Al salem, Hesham I. A.

    Stabilizing polysulfide-shuttle process while ensuring high sulfur loading holds the key to realize high theoretical energy density (2500 Wh/kg) of lithium-sulfur (Li-S) batteries. Though several carbon based porous materials have been used as host structures for sulfur and its intermediate polysulfides, the week adsorption of polysulfides on carbon surface and its poor reaction kinetics limits them from practical application. Here, we preset a novel electcatalysis approach to stabilize polysulfide shuttle process and also enhance its red-ox kinetics. As a proof of concept, we have studied in-detail using conventional electrocatalyst (Pt/graphene composite), further the same extended to cost-effective electrocatalysts such as WS2 nanosheets and Metal carbides for viable practical applications. Nature of electrocatalyst, concentration of polysulfides and temperature of the cell on electrochemical properties will be discussed. We reveal substantial improvement in electrochemical properties such as specific capacity, rate capability, and coulombic efficiency and corroborate our findings with systematic experimental studies. Interaction between electrocatalyst and polysulfides has been evaluated by conducting X-ray photoelectron spectroscopy and electron microscopy studies at various electrochemical conditions. As a conclusion, introducing a catalyst in the Li-S system will open a new avenue for improving electrochemical performance.

  18. Computational modeling of Li-ion batteries

    NASA Astrophysics Data System (ADS)

    Grazioli, D.; Magri, M.; Salvadori, A.

    2016-12-01

    This review focuses on energy storage materials modeling, with particular emphasis on Li-ion batteries. Theoretical and computational analyses not only provide a better understanding of the intimate behavior of actual batteries under operational and extreme conditions, but they may tailor new materials and shape new architectures in a complementary way to experimental approaches. Modeling can therefore play a very valuable role in the design and lifetime prediction of energy storage materials and devices. Batteries are inherently multi-scale, in space and time. The macro-structural characteristic lengths (the thickness of a single cell, for instance) are order of magnitudes larger than the particles that form the microstructure of the porous electrodes, which in turn are scale-separated from interface layers at which atomistic intercalations occur. Multi-physics modeling concepts, methodologies, and simulations at different scales, as well as scale transition strategies proposed in the recent literature are here revised. Finally, computational challenges toward the next generation of Li-ion batteries are discussed.

  19. The influence of temperature and salinity on the Li/Ca and d7Li of inorganic and biogenic carbonates

    NASA Astrophysics Data System (ADS)

    Marriott, C.; Staubwasser, M.; Crompton, R.; Henderson, G.

    2003-04-01

    Lithium is the sixth most abundant metal in the ocean. It is conservative with a residence time of around 1Ma and has two stable isotopes ^7Li and ^6Li that are not actively involved in biological processes. Isotopic fractionation is observed during incorporation into calcium carbonate but no previous work has systematically examined the controls on this fractionation. We have investigated Li incorporation and isotopic fraction in both inorganically precipitated calcite and coralline aragonite (1). In both cases there is an inverse correlation of Li concentration with temperature and no significant variation in isotopic fractionation. A decrease in D Li/Ca from 0.0092 to 0.0030 is seen over a temperature range of 5--30^oC, whilst an offset of approximately -8.5 ppm is seen in the δ^7Li ratio relative to the growth solution. The temperature dependence of Li/Ca has an increased sensitivity at low temperatures and might therefore be useful in examining changes in bottom water temperature. We are now investigating Li/Ca and δ^7Li of foraminifera. Previous work (2) has suggested little variability in Li/Ca with temperature, although this was for samples from warmer water where Li/Ca is not sensitive. In this study, Uvigerina are examined in a series of core top samples from the Arabian Sea with a depth range of 95--1800m and corresponding temperature range of 5--20^oC. A series of inorganic calcite samples have also been precipitated in order to examine the effect of salinity on Li/Ca, δ^7Li and δ44Ca over a salinity range of 10--50 psu. The distribution coefficient of Li shows a positive correlation with salinity over this range. δ^7Li and δ44Ca measurements for these samples are presently being analysed. (1) Marriott et al., 2002, GCA, 66, A485 (2) Delaney et al., 1985, GCA, 49, 1327

  20. First-principles simulations of the porous layered calcogenides Li2 +xSnO3 and Li2 +xSnS3

    NASA Astrophysics Data System (ADS)

    Howard, Jason; Holzwarth, N. A. W.

    2016-08-01

    First-principles simulations of the porous layered calcogenide materials Li2SnO3 and Li2SnS3 are used to study their structures, Li ion mobilities, and their interactions with excess Li. The pristine materials are characterized by a regular pattern of voids within the calcogenide layers which are occupied by intralayer Li ions. The energetically most favorable Li ion migration processes for both materials result in a net motion perpendicular to the layers and involve intralayer Li ions and nearby interstitial sites. The ideal lattice has eight symmetry related stable interstitial sites within the conventional unit cell which, in addition to participating in the Li ion migration processes, are also important for accommodating excess Li during lithiation processes. Consistent with experimental findings, the simulations find that the addition of Li atoms to Li2SnO3 results in a disruption of the calcogen lattice with the breaking of Sn-O bonds. The estimated voltage versus bcc Li for this system is in qualitative agreement with experiment provided that Sn/Li disorder is taken into account. By contrast, the simulations predict that the addition of Li atoms to Li2SnS3 results in a stable metallic material up to a stoichiometry of Li3SnS3 . This prediction has not yet been studied experimentally. Simulations of surfaces of these materials find that it is energetically favorable to add a small amount of excess surface Li. However, interfaces of these materials with Li metal are found to be reactive. Some of the findings may be relevant to other materials having the same crystal structure such as Li2MnO3 and Li2TiO3 .

  1. 8Li({alpha},n)11B at Big Bang Temperatures: Neutron Counting With a Low Intensity 8Li Radioactive Beam

    SciTech Connect

    Cherubini, S.; Rolfs, C.; Strieder, F.; Figuera, P.; Agodi, C.; Alba, R.; Calabretta, L.; Cosentino, L.; Del Zoppo, A.; Di Pietro, A.; Lamia, L.; Pappalardo, L.; Pizzone, R.G.; Musumarra, A.; Pellegriti, M.G.; Rinollo, A.; Romano, S.; Spitaleri, C.; Tudisco, S.; Tumino, A.

    2004-02-27

    The cross section of 8Li({alpha},n)11B is very important for the study of primordial nucleosinthesys models. In this paper we report on the production of a 8Li beam via the 7Li(d,p)8Li reaction at the Laboratori Nazionali del Sud. Also, a novel experimental technique for measuring the reaction 8Li({alpha},n)11B at energies of astrophysical interest has been implemented and tested.

  2. Continuous flame aerosol synthesis of carbon-coated nano-LiFePO4 for Li-ion batteries

    PubMed Central

    Waser, Oliver; Büchel, Robert; Hintennach, Andreas; Novák, Petr; Pratsinis, Sotiris E.

    2013-01-01

    Core-shell, nanosized LiFePO4-carbon particles were made in one step by scalable flame aerosol technology at 7 g/h. Core LiFePO4 particles were made in an enclosed flame spray pyrolysis (FSP) unit and were coated in-situ downstream by auto thermal carbonization (pyrolysis) of swirl-fed C2H2 in an O2-controlled atmosphere. The formation of acetylene carbon black (ACB) shell was investigated as a function of the process fuel-oxidant equivalence ratio (EQR). The core-shell morphology was obtained at slightly fuel-rich conditions (1.0 < EQR < 1.07) whereas segregated ACB and LiFePO4 particles were formed at fuel-lean conditions (0.8 < EQR < 1). Post-annealing of core-shell particles in reducing environment (5 vol% H2 in argon) at 700 °C for up to 4 hours established phase pure, monocrystalline LiFePO4 with a crystal size of 65 nm and 30 wt% ACB content. Uncoated LiFePO4 or segregated LiFePO4-ACB grew to 250 nm at these conditions. Annealing at 800 °C induced carbothermal reduction of LiFePO4 to Fe2P by ACB shell consumption that resulted in cavities between carbon shell and core LiFePO4 and even slight LiFePO4 crystal growth but better electrochemical performance. The present carbon-coated LiFePO4 showed superior cycle stability and higher rate capability than the benchmark, commercially available LiFePO4. PMID:23407817

  3. Continuous flame aerosol synthesis of carbon-coated nano-LiFePO(4) for Li-ion batteries.

    PubMed

    Waser, Oliver; Büchel, Robert; Hintennach, Andreas; Novák, Petr; Pratsinis, Sotiris E

    2011-10-01

    Core-shell, nano-sized LiFePO(4)-carbon particles were made in one step by scalable flame aerosol technology at 7 g/h. Core LiFePO(4) particles were made in an enclosed flame spray pyrolysis (FSP) unit and were coated in-situ downstream by auto thermal carbonization (pyrolysis) of swirl-fed C(2)H(2) in an O(2)-controlled atmosphere. The formation of acetylene carbon black (ACB) shell was investigated as a function of the process fuel-oxidant equivalence ratio (EQR). The core-shell morphology was obtained at slightly fuel-rich conditions (1.0LiFePO(4) particles were formed at fuel-lean conditions (0.8LiFePO(4) with a crystal size of 65 nm and 30 wt% ACB content. Uncoated LiFePO(4) or segregated LiFePO(4)-ACB grew to 250 nm at these conditions. Annealing at 800 °C induced carbothermal reduction of LiFePO(4) to Fe(2)P by ACB shell consumption that resulted in cavities between carbon shell and core LiFePO(4) and even slight LiFePO(4) crystal growth but better electrochemical performance. The present carbon-coated LiFePO(4) showed superior cycle stability and higher rate capability than the benchmark, commercially available LiFePO(4).

  4. Screening Li-ion batteries for internal shorts

    NASA Astrophysics Data System (ADS)

    Darcy, Eric

    A Li-ion polymer pouch cell battery design for a spacesuit developed an internal short during ground storage. A detailed failure investigation found that native contamination was the most probable root cause as the failure mechanism was successfully replicated. Lessons learned are applicable to the implementation of most Li-ion cell designs for critical applications.

  5. Si(Li) X-ray astronomical spectroscopy

    NASA Technical Reports Server (NTRS)

    Holt, S. S.

    1975-01-01

    The general considerations involved in the choice of Si(Li) as a non-dispersive spectrometer for X-ray astronomy are discussed. In particular, its adaptation to HEAO-B is described as an example of the space-borne application of Si(Li) technology.

  6. NASA/GSFC Testing of Li-Ion Cells: Update

    NASA Technical Reports Server (NTRS)

    Vaidyanathan, Hari; Rao, Gopalakrishna M.

    2001-01-01

    This viewgraph paper presents a report on the ongoing testing of Lithium Ion (Li-Ion) cells. Characterizes cells according to capacity, self-discharge, and mid-discharge voltage. Determines the cycling performance of Li-Ion cells as batteries according to number of cycles, charge voltage, and temperature.

  7. An Introduction to the RoLI[TM

    ERIC Educational Resources Information Center

    Meyer, Jan H. F.

    2004-01-01

    The Reflections on Learning Inventory (RoLI) is an instrument designed to capture variation in students' engagement of learning--typically in a given disciplinary context or topic-specific 'episode'. Although the RoLI has been employed as a research instrument in a number of published studies on the modelling of student learning in higher…

  8. Recent development of hyperspectral LiDAR using supercontinuum laser

    NASA Astrophysics Data System (ADS)

    Wang, Zhen; Li, Chuanrong; Zhou, Mei; Zhang, Huijing; He, Wenjing; Li, Wei; Qiu, Yuanyuan

    2016-10-01

    Hyperspectral Light Detection And Ranging (Hyperspectral LiDAR), a recently developed technique, combines the advantages of the LiDAR and hyperspectral imaging and has been attractive for many applications. Supercontinuum laser (SC laser), a rapidly developing technique offers hyperspectral LiDAR a suitable broadband laser source and makes hyperspectral Lidar become an installation from a theory. In this paper, the recent research and progressing of the hyperspectral LiDAR are reviewed. The hyperspectral LiDAR has been researched in theory, prototype system, instrument, and application experiment. However, the pulse energy of the SC laser is low so that the range of the hyperspectral LiDAR is limited. Moreover, considering the characteristics of sensors and A/D converter, in order to obtain the full waveform of the echo, the repetition rate and the pulse width of the SC laser needs to be limited. Recently, improving the detection ability of hyperspectral LiDAR, especially improving the detection range, is a main research area. A higher energy pulse SC laser, a more sensitive sensor, or some algorithms are applied in hyperspectral LiDAR to improve the detection distance from 12 m to 1.5 km. At present, a lot of research has been focused on this novel technology which would be applied in more applications.

  9. Praseodymium-doped Ti:LiNbO3 waveguides

    NASA Astrophysics Data System (ADS)

    Baumann, I.; Cusso, F.; Herreros, B.; Holzbrecher, H.; Paulus, H.; Schäfer, K.; Sohler, W.

    The incorporation of praseodymium into LiNbO3 by diffusion doping is investigated by means of secondary neutral mass spectrometry and secondary ion mass spectrometry. The diffusion of praseodymium in LiNbO3 can be described by Fick's laws of diffusion with a concentration-independent diffusion coefficient and a limited solubility of praseodymium in LiNbO3 increasing exponentially with rising temperature. The diffusion depends on the Li2O content of the LiNbO3 crystal. For LiNbO3 crystals with a nominal slight difference in the congruent composition, the diffusion constants and activation energies for Z-cut LiNbO3 are 3.28×10-5 cm2/s and 2.27 eV, and 1.39×10-5 cm2/s and 2.24 eV, respectively. Titanium-doped waveguides are formed in Pr:LiNbO3 and characterised in relation to waveguide loss and absorption in the visible and near infrared.

  10. Group 31 and Group 34 Li-ion Battery Specification

    DTIC Science & Technology

    2011-02-08

    Unclassified 1 Unclassified United States Army Group 31 and Group 34 Li- ion Battery Specification US Army TARDEC Energy Storage Team...7 1.1.17 Standard Battery Charger ...Requirements The following are requirements for the Li ion rechargeable battery conforming to the Group 31 and Group 34 form factor. These are based on

  11. Understanding oxygen reactions in aprotic Li-O2 batteries

    NASA Astrophysics Data System (ADS)

    Shunchao, Ma; Yelong, Zhang; Qinghua, Cui; Jing, Zhao; Zhangquan, Peng

    2016-01-01

    Although significant progress has been made in many aspects of the emerging aprotic Li-O2 battery system, an in-depth understanding of the oxygen reactions is still underway. The oxygen reactions occurring in the positive electrode distinguish Li-O2 batteries from the conventional Li-ion cells and play a crucial role in the Li-O2 cell’s performance (capacity, rate capability, and cycle life). Recent advances in fundamental studies of oxygen reactions in aprotic Li-O2 batteries are reviewed, including the reaction route, kinetics, morphological evolution of Li2O2, and charge transport within Li2O2. Prospects are also provided for future fundamental investigations of Li-O2 chemistry. Project supported by the Recruitment Program of Global Youth Experts of China, the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA09010401), the Science and Technology Development Program of Jilin Province, China (Grant No. 20150623002TC), and the Natural Science Foundation of Jiangsu Province, China (Grant No. BK20131139).

  12. Nanostructured Materials for Li-Ion Batteries and Beyond.

    PubMed

    Li, Xifei; Sun, Xueliang

    2016-04-07

    This Special Issue "Nanostructured Materials for Li-Ion Batteries and Beyond" of Nanomaterials is focused on advancements in the synthesis, optimization, and characterization of nanostructured materials, with an emphasis on the application of nanomaterials for building high performance Li-ion batteries (LIBs) and future systems.[...].

  13. [MECHANISMS OF THE EFFECT OF Li+ ON MYOCARDIUM OF VERTEBRATES].

    PubMed

    Shemarova, I V; Korotkov, S M; Nesterov, V P

    2015-01-01

    The effect of Li+ on the frog Rana temporaria myocardium and its influence on the ion transport in the rat heart mitochondria (RHM) were studied. Li+ added to the normal Ringer solution (Li(+)-R) was found to attenuate myocardial tension, decrease the maximal rate of tension development and its half-relaxation time. Comparison of the cardiac muscle contraction parameters in the Li(+)-R with the effect of the voltage-gated Ca(2+)-channels (Cav1.2), verapamil and CdCl2, showed that the negative inotropic effect of the Na+ replacement by Li+ in the limited intermembrane ("fuzzy") space is underlain by the blocking of Ca2+ influx into the myoplasm via the reverse Ca2+/Na(+)-exchanger in the plasma membrane (PM). This, in turn, prevents Ca(2+)-induced massive Ca2+ release into the myoplasm via the RYR2-channels in the sarcoplasmic reticulum (SR) leading in aggregate to suppression of Ca(2+)-dependent myocardial contractions. In the experimental studies of the Li+ effect on the RHM it was established that Li+ just slightly increases the passive permeability of the inner mitochondrial membrane (IMM) for K+ and H+ and decreases the intensity of ion pumping out of the energized mitochondrial matrix to the external medium. This may also indicate the lack of relationship between the mitochondrial oxidative processes and the reduction in the myocardial contractile activity under the Na+ replacement by Li+.

  14. An Update on C458 AI-Li for Cryotanks

    NASA Technical Reports Server (NTRS)

    Babel, Henry W.; Rioja, Roberto; Jata, Kumar

    2003-01-01

    This viewgraph representation provides an overview of ongoing research being conducted on C458 Al-Li composite cryotanks. Topics covered include: structural design of C458 Al-Li cryotanks, C458 ingot casting capability, C458 plate properties, summary of attained properties, design database capabilities, fatigue tests and testing, and ongoing research projects.

  15. Oxygen Luminescence Centers in LiF-MeO Crystals

    NASA Astrophysics Data System (ADS)

    Lisitsyna, L. A.; Suleimen, R. N.

    2017-08-01

    Spectral-kinetic parameters of luminescence of LiF crystals doped with various polyvalent metal oxides (Li, Ti, Fe, W, U) were studied in the temperature range of 100-300 K and the absorbed doses range of 0-105 Gy. A model for describing polyvalent activation cation role in the processes of radiation energy dissipation in the crystal volume is suggested.

  16. Superconductivity in Li-doped α-rhombohedral boron

    NASA Astrophysics Data System (ADS)

    Nagatochi, T.; Hyodo, H.; Sumiyoshi, A.; Soga, K.; Sato, Y.; Terauchi, M.; Esaka, F.; Kimura, K.

    2011-05-01

    Metal transition and superconductivity were observed in Li-doped α-rhombohedral boron (α-B12). The authors have established a purification method and obtained a large amount of high-purity α-B12 powder. Li doping into purified α-B12 was attempted by vapor diffusion processing (VDP) in a Mo or Ta tube. Li-doped α-B12 contained metallic glittering particles. Meissner effects were observed in such a compound with the nominal composition LixB12 (x = 1.0, 1.4, 1.5, 1.7, or 2.5) (Tc = 3.2-7 K). As for Li2.5B12, the temperature dependence of its electrical conductivity indicates a metallic character and its electrical resistivity drop is detected near the Meissner temperature. The existence of Li and Fermi edges in Li-doped α-B12 crystals was verified by transmission electron microscopy-electron energy loss spectroscopy (TEM-EELS). Lattice expansion, which is a well-known indicator of metal doping into a crystal, was also observed. Thus, Li doping into α-B12 was successfully achieved. Our work also suggests that it is possible to dope a larger amount of Li into α-B12 and to increase its Tc.

  17. LiDAR - An emerging tool for geological applications

    USGS Publications Warehouse

    Stoker, Jason M.

    2012-01-01

    Over the past five to ten years the use and applicability of light detection and ranging (LiDAR) technology has increased dramatically. As a result, more and more LiDAR data now are being collected across the country for a wide range of applications, and LiDAR currently is the technology of choice for high resolution terrain model creation, 3-D city and infrastructure modeling, forestry, and a wide range of scientific applications. LiDAR is a key technology for geological applications both within and outside the U.S. Geological Survey, and efforts are underway to try to collect high resolution LiDAR data for the entire United States (https://pubs.usgs.gov/fs/2012/3089/pdf/fs2012-3089.pdf).

  18. Polymer electrolytes for a rechargeable li-Ion battery

    SciTech Connect

    Argade, S.D.; Saraswat, A.K.; Rao, B.M.L.; Lee, H.S.; Xiang, C.L.; McBreen, J.

    1996-10-01

    Lithium-ion polymer electrolyte battery technology is attractive for many consumer and military applications. A Li{sub x}C/Li{sub y}Mn{sub 2}O{sub 4} battery system incorporating a polymer electrolyte separator base on novel Li-imide salts is being developed under sponsorship of US Army Research Laboratory (Fort Monmouth NJ). This paper reports on work currently in progress on synthesis of Li-imide salts, polymer electrolyte films incorporating these salts, and development of electrodes and cells. A number of Li salts have been synthesized and characterized. These salts appear to have good voltaic stability. PVDF polymer gel electrolytes based on these salts have exhibited conductivities in the range 10{sup -4} to 10{sub -3} S/cm.

  19. Recombination luminescence from electron-irradiated Li-diffused Si

    NASA Technical Reports Server (NTRS)

    Johnson, E. S.; Compton, W. D.; Noonan, J. R.; Streetman, B. G.

    1973-01-01

    Lithium doping has a dramatic effect on the low-temperature photoluminescence of electron-irradiated Si. In oxigen-lean Si with Li doping, a new irradiation-dependent luminescence band between 0.75 and 1.05 eV is observed, which is dominated by a zero-phonon peak at 1.045 eV. This band is believed to be due to radiative transitions involving a Li-modified divacancy. This band is present also in oxygen-rich, Li-diffused Si and is accompanied by bands previously related to the Si-G15(K) center and the divacancy. The intensities of the Li-modified divacancy and Si-G15(K) center bands are relatively weak in the oxygen-rich material, apparently due to the formation of lithium-oxygen complexes which reduce the concentration of unassociated interstitial Li and O.

  20. Reversible storage of hydrogen in destabilized LiBH4.

    PubMed

    Vajo, John J; Skeith, Sky L; Mertens, Florian

    2005-03-10

    Destabilization of LiBH4 for reversible hydrogen storage has been studied using MgH2 as a destabilizing additive. Mechanically milled mixtures of LiBH4 + (1/2)MgH2 or LiH + (1/2)MgB2 including 2-3 mol % TiCl3 are shown to reversibly store 8-10 wt % hydrogen. Variation of the equilibrium pressure obtained from isotherms measured at 315-400 degrees C indicate that addition of MgH2 lowers the hydrogenation/dehydrogenation enthalpy by 25 kJ/(mol of H2) compared with pure LiBH4. Formation of MgB2 upon dehydrogenation stabilizes the dehydrogenated state and, thereby, destabilizes the LiBH4. Extrapolation of the isotherm data yields a predicted equilibrium pressure of 1 bar at approximately 225 degrees C. However, the kinetics were too slow for direct measurements at these temperatures.

  1. Recombination luminescence from electron-irradiated Li-diffused Si

    NASA Technical Reports Server (NTRS)

    Johnson, E. S.; Compton, W. D.; Noonan, J. R.; Streetman, B. G.

    1973-01-01

    Lithium doping has a dramatic effect on the low-temperature photoluminescence of electron-irradiated Si. In oxigen-lean Si with Li doping, a new irradiation-dependent luminescence band between 0.75 and 1.05 eV is observed, which is dominated by a zero-phonon peak at 1.045 eV. This band is believed to be due to radiative transitions involving a Li-modified divacancy. This band is present also in oxygen-rich, Li-diffused Si and is accompanied by bands previously related to the Si-G15(K) center and the divacancy. The intensities of the Li-modified divacancy and Si-G15(K) center bands are relatively weak in the oxygen-rich material, apparently due to the formation of lithium-oxygen complexes which reduce the concentration of unassociated interstitial Li and O.

  2. At the Cosmonaut Hotel in Baikonur, Kazakhstan, Expedition 48-49 crewmembers Takuya Onishi of the Japan Aerospace Exploration Agency (left) and Anatoly Ivanishin of Roscosmos share a game of ping-pong June 30 during pre-launch activities. They and Kate Rubins of NASA will launch July 7, Baikonur time, on the Soyuz MS-01 spacecraft for a planned four-month mission on the International Space Station...NASA/Alexander Vysotsky.

    NASA Image and Video Library

    2016-06-30

    At the Cosmonaut Hotel in Baikonur, Kazakhstan, Expedition 48-49 crewmembers Takuya Onishi of the Japan Aerospace Exploration Agency (left) and Anatoly Ivanishin of Roscosmos share a game of ping-pong June 30 during pre-launch activities. They and Kate Rubins of NASA will launch July 7, Baikonur time, on the Soyuz MS-01 spacecraft for a planned four-month mission on the International Space Station. NASA/Alexander Vysotsky

  3. On the relative abundance of LiH and LiH+ molecules in the early universe: new results from quantum reactions

    NASA Astrophysics Data System (ADS)

    Bovino, S.; Tacconi, M.; Gianturco, F.

    2011-05-01

    The chemistry of Li in the early universe has been discussed in the past, reaching contrasting conclusions (see e.g., SLD96; BG97; GP98; Vonlanthen et al. 2009). Of critical relevance, is the uncertainty in the knowledge of reliable reaction rates for the destruction of LiH and LiH^+ molecules formed by radiative recombination (Dickinson & Gadéa 2000) via strongly exothermic reactions without entrance barriers: LiH + H → Li + H_2 LiH + H^+ → Li + H_2^+ and LiH^+ + H → Li^+ + H_2. Therefore, it is an accurate knowledge of the reaction rates for the above processes, at low redshift values, that can ultimately tell us what the end-role of the LiH/LiH^+ systems could be as efficient coolants under early universe conditions. The task of the present work is to show that the reaction rates recently determined from fully ab-initio quantum methods (Bovino et al. 2009, 2010a, 2010b), which also employ accurate interaction forces between partners, have a significant impact on the evolution of LiH and LiH^+ during the post-recombination era of the early universe. We shall further show that a more realistic description of the rates for a neutralization process LiH^+ + e^- → Li + H could substantially change the relative abundance of the ionic molecular species.

  4. A High-Performance Li-O2 Battery with a Strongly Solvating Hexamethylphosphoramide Electrolyte and a LiPON-Protected Lithium Anode.

    PubMed

    Zhou, Bin; Guo, Limin; Zhang, Yantao; Wang, Jiawei; Ma, Lipo; Zhang, Wen-Hua; Fu, Zhengwen; Peng, Zhangquan

    2017-08-01

    The aprotic Li-O2 battery has attracted a great deal of interest because theoretically it can store more energy than today's Li-ion batteries. However, current Li-O2 batteries suffer from passivation/clogging of the cathode by discharged Li2 O2 , high charging voltage for its subsequent oxidation, and accumulation of side reaction products (particularly Li2 CO3 and LiOH) upon cycling. Here, an advanced Li-O2 battery with a hexamethylphosphoramide (HMPA) electrolyte is reported that can dissolve Li2 O2 , Li2 CO3 , and LiOH up to 0.35, 0.36, and 1.11 × 10(-3) m, respectively, and a LiPON-protected lithium anode that can be reversibly cycled in the HMPA electrolyte. Compared to the benchmark of ether-based Li-O2 batteries, improved capacity, rate capability, voltaic efficiency, and cycle life are achieved for the HMPA-based Li-O2 cells. More importantly, a combination of advanced research techniques provide compelling evidence that operation of the HMPA-based Li-O2 battery is backed by nearly reversible formation/decomposition of Li2 O2 with negligible side reactions. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Solution-processable glass LiI-Li4SnS4 superionic conductors for all-solid-state Li-ion batteries

    SciTech Connect

    Kern Ho Park; Oh, Dae Yang; Choi, Young Eun; Nam, Young Jin; Han, Lili; Kim, Ju -Young; Xin, Huolin; Lin, Feng; Oh, Seung M.; Jung, Yoon Seok

    2015-12-22

    The new, highly conductive (4.1 × 10–4 S cm–1 at 30 °C), highly deformable, and dry-air-stable glass 0.4LiI-0.6Li4SnS4 is prepared using a homogeneous methanol solution. Furthermore, the solution process enables the wetting of any exposed surface of the active materials with highly conductive solidified electrolytes (0.4LiI-0.6Li4SnS4), resulting in considerable improvements in electrochemical performances of these electrodes over conventional mixture electrodes.

  6. Structural characterization of slightly boron-deficient LiB, LiB0.9 and LiB0.8, under pressure.

    PubMed

    Suarez-Alcubilla, Ainhoa; Gurtubay, Idoia G; Bergara, Aitor

    2014-11-26

    Results of computational investigations of two slightly boron-deficient lithium borides, LiB(0.9) and LiB(0.8), under pressure are reported. Structure predictions based on particle swarm optimization reveal that at low pressure both compositions adopt chain structures, as stoichiometric 1 : 1 LiB. With increasing pressure both undergo phase transitions to layered arrangements. The evolution of the structural parameters of these stoichiometries as a function of pressure and the results obtained from the enthalpies indicate that boron-deficient structures are more favoured than 1 : 1 LiB, even at zero pressure. Moreover, as pressure is increased a larger deficiency in B seems to be favoured.

  7. Comparison between the low temperature thermoluminescence spectra in annealed LiF:Mg,Cu, LiF:Mg,Cu,P and LiF:Mg,Cu,Si

    NASA Astrophysics Data System (ADS)

    Yang, B.; Wang, L.; Townsend, P. D.; Gao, H.

    2008-06-01

    Two strong thermal peaks in the wavelength range 220-420 nm have been detected at 128 and 140 K in LiF:Mg,Cu, at 123 and 135 K in LiF:Mg,Cu,P and at 125 and 133 K in LiF:Mg,Cu,Si, respectively. The origin of these main TL peaks is discussed in terms of defect perturbed H-F and VK-e type recombination, respectively. The relative intensity between the two peaks in each sample and the emission spectra are dependent on the dopants. Annealing at 240-390 °C can modify the low temperature TL features, especially in those samples doped with three impurities. The low temperature data give some clues to select most favourable dopants for future LiF-type dosimeters.

  8. Fast Li ion dynamics in the solid electrolyte Li7 P3 S11 as probed by (6,7) Li NMR spin-lattice relaxation.

    PubMed

    Wohlmuth, Dominik; Epp, Viktor; Wilkening, Martin

    2015-08-24

    The development of safe and long-lasting all-solid-state batteries with high energy density requires a thorough characterization of ion dynamics in solid electrolytes. Commonly, conductivity spectroscopy is used to study ion transport; much less frequently, however, atomic-scale methods such as nuclear magnetic resonance (NMR) are employed. Here, we studied long-range as well as short-range Li ion dynamics in the glass-ceramic Li7 P3 S11 . Li(+) diffusivity was probed by using a combination of different NMR techniques; the results are compared with those obtained from electrical conductivity measurements. Our NMR relaxometry data clearly reveal a very high Li(+) diffusivity, which is reflected in a so-called diffusion-induced (6) Li NMR spin-lattice relaxation peak showing up at temperatures as low as 313 K. At this temperature, the mean residence time between two successful Li jumps is in the order of 3×10(8) s(-1) , which corresponds to a Li(+) ion conductivity in the order of 10(-4) to 10(-3) S cm(-1) . Such a value is in perfect agreement with expectations for the crystalline but metastable glass ceramic Li7 P3 S11 . In contrast to conductivity measurements, NMR analysis reveals a range of activation energies with values ranging from 0.17 to 0.26 eV, characterizing Li diffusivity in the bulk. In our case, through-going Li ion transport, when probed by using macroscopic conductivity spectroscopy, however, seems to be influenced by blocking grain boundaries including, for example, amorphous regions surrounding the Li7 P3 S11 crystallites. As a result of this, long-range ion transport as seen by impedance spectroscopy is governed by an activation energy of approximately 0.38 eV. The findings emphasize how surface and grain boundary effects can drastically affect long-range ionic conduction. If we are to succeed in solid-state battery technology, such effects have to be brought under control by, for example, sophisticated densification or through the preparation

  9. Relaxation-Induced Memory Effect of LiFePO4 Electrodes in Li-Ion Batteries.

    PubMed

    Jia, Jianfeng; Tan, Chuhao; Liu, Mengchuang; Li, De; Chen, Yong

    2017-07-26

    In Li-ion batteries, memory effect has been found in several commercial two-phase materials as a voltage bump and a step in the (dis)charging plateau, which delays the two-phase transition and influences the estimation of the state of charge. Although memory effect has been first discovered in olivine LiFePO4, the origination and dependence are still not clear and are critical for regulating the memory effect of LiFePO4. Herein, LiFePO4 has been synthesized by a home-built spray drying instrument, of which the memory effect has been investigated in Li-ion batteries. For as-synthesized LiFePO4, the memory effect is significantly dependent on the relaxation time after phase transition. Besides, the voltage bump of memory effect is actually a delayed voltage overshooting that is overlaid at the edge of stepped (dis)charging plateau. Furthermore, we studied the kinetics of LiFePO4 electrode with electrochemical impedance spectroscopy (EIS), which shows that the memory effect is related to the electrochemical kinetics. Thereby, the underlying mechanism has been revealed in memory effect, which would guide us to optimize two-phase electrode materials and improve Li-ion battery management systems.

  10. Kinetic measurement and prediction of the hydrogen outgassing from the polycrystalline LiH/LiOH system

    SciTech Connect

    Dinh, L N; Grant, D M; Schildbach, M A; Smith, R A; Leckey, J H; Siekhaus, W J; Balazs, B; McLean II, W

    2005-03-09

    In this report, we present the use of temperature programmed reaction/decomposition (TPR) in the isoconversion mode to measure outgassing kinetics and to make kinetic prediction concerning hydrogen release from the polycrystalline LiH/LiOH system in the absence of any external H{sub 2}O source.

  11. The properties of and analytical methods for detection of LiOH and Li2CO3

    NASA Technical Reports Server (NTRS)

    Selvaduray, Guna

    1991-01-01

    Lithium hydroxide (LiOH) is used as a CO2 absorbent in the Shuttle Extravehicular Mobility Unit (EMU) Portable Life Support System (PLSS). The first objective was to survey parameters that may be used to indicate conversion of LiOH to Li2CO3, and compile a list of all possible properties, including physical, chemical, structural, and electrical, that may serve to indicate the occurrence of reaction. These properties were compiled for the reactant (LiOH), the intermediate monohydrate compound (LiOH.H2O), and the final product (Li2CO3). The second objective was to survey measurement and analytical techniques which may be used in conjunction with each of the properties identified above, to determine the extent of conversion of LiOH to Li2CO3. Both real-time and post-run techniques were of interest. The techniques were also evaluated in terms of complexity, technology readiness, materials/equipment availability, and cost, where possible.

  12. The Use of Redox Mediators for Enhancing Utilization of Li2S Cathodes for Advanced Li-S Battery Systems.

    PubMed

    Meini, Stefano; Elazari, Ran; Rosenman, Ariel; Garsuch, Arnd; Aurbach, Doron

    2014-03-06

    The development of Li2S electrodes is a crucial step toward industrial manufacturing of Li-S batteries, a promising alternative to Li-ion batteries due to their projected two times higher specific capacity. However, the high voltages needed to activate Li2S electrodes, and the consequent electrolyte solution degradation, represent the main challenge. We present a novel concept that could make feasible the widespread application of Li2S electrodes for Li-S cell assembly. In this concept, the addition of redox mediators as additives to the standard electrolyte solution allows us to recover most of Li2S theoretical capacity in the activation cycle at potentials as low as 2.9 VLi, substantially lower than the typical potentials >4 VLi needed with standard electrolyte solution. Those novel additives permit us to preserve the electrolyte solution from being degraded, allowing us to achieve capacity as high as 500 mAhg(-1)Li2S after 150 cycles with no major structural optimization of the electrodes.

  13. Synthesis and characterization of PVA blended LiClO4 as electrolyte material for battery Li-ion

    NASA Astrophysics Data System (ADS)

    Gunawan, I.; Deswita; Sugeng, B.; Sudaryanto

    2017-07-01

    It have been synthesized the materials for Li ion battery electrolytes, namely PVA with the addition of LiClO4 salt were varied 0, 5, 10, 15 and 20% by weight respectively. The objective of this study is to control the ionic conductivity in traditional polymer electrolytes, to improve ionic conductivity with the addition of lithium perchlorat (LiClO4). These electrolyte materials prepared by PVA powder was dissolved into distilled water and added LiClO4 salt were varied. After drying the solution, PVA sheet blended LiClO4 salt as electrolyte material for Li ion battery obtained. PVA blended LiClO4 salt crystallite form was confirmed using X-Ray Difraction (XRD) equipment. Observation of the morphology done by using Scanning Electron Microscope (SEM). While the electrical conductivity of the material is measured using LCR meter. The results of XRD pattern of LiClO4 shows intense peaks at angles 2θ = 23.2, 32.99, and 36.58°, which represent the crystalline nature of the salt. Particles morphology of the sample revealed by scanning electron microscopy are irregular in shape and agglomerated, with mean size 200-300 nm. It can be concluded that polycrystalline particles are composed of large number of crystallites. The study of conductivity by using LCR meter shows that all the graphs represent the DC and AC conductivity phenomena.

  14. Optical waveguides in LiNbO3 and stoichiometric LiNbO3 crystals by proton exchange

    NASA Astrophysics Data System (ADS)

    Li, Shiling

    2008-10-01

    The formation of optical planar waveguides in LiNbO3 and stoichiometric LiNbO3 crystals by proton exchange was reported. The prism-coupling method was used to characterize the dark-line spectroscopy at the wavelength of 633 and 1539 nm, respectively. The mode optical near-field outputs from proton-exchanged LiNbO3 and SLN waveguides at 633 nm were presented. The mode field from stoichiometric LiNbO3 (SLN) waveguide is lighter and more uniform than that from LiNbO3 waveguide, which means the quality of the waveguide in SLN crystal is better than that of the LiNbO3 waveguide. For proton-exchanged LiNbO3 waveguides, the evolution of the refractive index profile with annealing was presented. The disorder profiles of Nb atoms in proton-exchanged LiNbO3 waveguides were obtained by Rutherford backscattering/channeling technique. It is shown that the longer the exchange time, the larger the displacement of Nb atoms.

  15. Dynamic studies of {sup 11}Li and its core {sup 9}Li on {sup 208}Pb near the Coulomb barrier

    SciTech Connect

    Cubero, M.; Borge, M. J. G.; Alcorta, M.; Madurga, M.; Tengblad, O.; Acosta, L.; Martel, I.; Sanchez-Benitez, A. M.; Alvarez, M. A. G.; Gomez-Camacho, J.; Diget, C.; Galaviz, D.; Fernandez-Garcia, J. P.; Lay, J. A.; Moro, A. M.; Mukha, I.; Shotter, A.; Walden, P.

    2010-04-26

    We measured the scattering of the halo nucleus {sup 11}Li and its core {sup 9}Li on the lead target at TRIUMF at energies below and around to the Coulomb barrier. We report here on our preliminary analysis of the inclusive breakup reaction.

  16. Enhanced ionic conductivity with Li7O2Br3 phase in Li3OBr anti-perovskite solid electrolyte

    NASA Astrophysics Data System (ADS)

    Zhu, Jinlong; Li, Shuai; Zhang, Yi; Howard, John W.; Lü, Xujie; Li, Yutao; Wang, Yonggang; Kumar, Ravhi S.; Wang, Liping; Zhao, Yusheng

    2016-09-01

    Cubic anti-perovskites with general formula Li3OX (X = Cl, Br, I) were recently reported as superionic conductors with the potential for use as solid electrolytes in all-solid-state lithium ion batteries. These electrolytes are nonflammable, low-cost, and suitable for thermoplastic processing. However, the primary obstacle of its practical implementation is the relatively low ionic conductivity at room temperature. In this work, we synthesized a composite material consisting of two anti-perovskite phases, namely, cubic Li3OBr and layered Li7O2Br3, by solid state reaction routes. The results indicate that with the phase fraction of Li7O2Br3 increasing to 44 wt. %, the ionic conductivity increased by more than one order of magnitude compared with pure phase Li3OBr. Formation energy calculations revealed the meta-stable nature of Li7O2Br3, which supports the great difficulty in producing phase-pure Li7O2Br3 at ambient pressure. Methods of obtaining phase-pure Li7O2Br3 will continue to be explored, including both high pressure and metathesis techniques.

  17. Enhanced ionic conductivity with Li7O2Br3 phase in Li3OBr anti-perovskite solid electrolyte

    DOE PAGES

    Zhu, Jinlong; Li, Shuai; Zhang, Yi; ...

    2016-09-07

    Cubic anti-perovskites with general formula Li3OX (X = Cl, Br, I) were recently reported as superionic conductors with the potential for use as solid electrolytes in all-solid-state lithium ion batteries. These electrolytes are nonflammable, low-cost, and suitable for thermoplastic processing. However, the primary obstacle of its practical implementation is the relatively low ionic conductivity at room temperature. In this work, we synthesized a composite material consisting of two anti-perovskite phases, namely, cubic Li3OBr and layered Li7O2Br3, by solid state reaction routes. The results indicate that with the phase fraction of Li7O2Br3 increasing to 44 wt. %, the ionic conductivity increasedmore » by more than one order of magnitude compared with pure phase Li3OBr. Formation energy calculations revealed the meta-stable nature of Li7O2Br3, which supports the great difficulty in producing phase-pure Li7O2Br3 at ambient pressure. Here, methods of obtaining phase-pure Li7O2Br3 will continue to be explored, including both high pressure and metathesis techniques.« less

  18. Elucidation and Comparison of the Effect of LiTFSI and LiNO3 Salts on Discharge Chemistry in Nonaqueous Li-O2 Batteries.

    PubMed

    Iliksu, Merve; Khetan, Abhishek; Yang, Shuo; Simon, Ulrich; Pitsch, Heinz; Sauer, Dirk Uwe

    2017-06-07

    The role of lithium salts in determining the discharge capacity of Li-O2 batteries has been highlighted in several recent studies; however, questions pertaining to their effect on the cathode surface and in the solution phase still remain unanswered. We conducted galvanostatic discharge experiments with different compositions of a binary mixture of 1 M of LiNO3 and LiTFSI in tetraglyme (TEGDME) as the electrolyte and analyzed the discharge products using techniques such as FT-IR, Raman spectroscopy, and SEM. It was observed that there is a nonlinear correlation between the electrolyte composition and the first discharge capacity, with the highest discharge capacity achieved with the electrolyte composition as 0.75 M LiNO3 and 0.25 M LiTFSI. The ID/IG values obtained from Raman spectroscopy, which represent the degree of order in the carbon cathode surface, were found to be correlated to the measured capacity. Our results indicate that at concentrations of LiNO3 higher than 0.75 M in the electrolyte, nitrogen doping of the carbon surface reaches a critical limit, beyond which it becomes unfavorable for the discharge process. On the other hand, decomposition of the electrolyte and formation of an amorphous layer on the cathode surface was found to intensify with increasing LiTFSI concentration. Our results show that the maximum discharge capacity of the cells is strongly dependent on the surface structure of the carbon cathode, which in turn is heavily influenced by the electrolyte composition. Classical molecular dynamics simulations of the same system indicated no such nonlinearity in the co-ordination of Li(+) ions with respect to electrolyte composition, indicating that the ionic association strength of the anion may have only a limited effect.

  19. Pressure-induced ferroelectric to paraelectric transition in LiTaO3 and (Li,Mg)TaO3

    DOE PAGES

    Yamanaka, Takamitsu; Nakamoto, Yuki; Takei, Fumihiko; ...

    2016-02-16

    X-ray powder diffraction and Raman scattering of LiTaO3 (LT) and (Li,Mg)TaO3 (LMT) have been measured under pressure up to 46 GPa. Above 30 GPa, the ferroelectric rhombohedral phase (R3c, Z – 6) of LiTaO3 transforms to a paraelectric orthorhombic phase (Pnma with Z – 4) with a large hysteresis. Rietveld profile fitting analysis shows that the Li-O bond is compressed and approaches that of Ta-O with pressure. The cation distribution analysis of the orthorhombic perovskite structure shows that Li and Ta are located in the octahedral 8-fold coordination sites. Difference Fourier |Fobs(hkl)| - |Fcal(hkl)| maps of LiTaO3 and (Li,Mg)TaO3 indicatemore » polarization in the c axis direction and a more distinct electron density distribution around the Ta position for (Li,Mg)TaO3 compared to LiTaO3. The observed effective charges indicate that for (Li,Mg)TaO3 without vacancies Ta5+ becomes less ionized as a function of Mg substitution. Considering both site occupancy and effective charge analysis, Ta5+ is reduced to Ta4.13+. Mg2+ and O2- change to Mg1.643+ and O1.732 -, respectively. The space- and time-averaged structures of the dynamical vibration of atoms can be elucidated from the electron density analysis by difference Fourier and temperature factors T(hkl) in the structure refinement. The refinement of the temperature factor is consistent with the cation distribution assuming full stoichiometry. The residual electron density induced from the excess electron in (Li,Mg)TaO3 indicates more electrons around the Ta site, as confirmed by the effective charge analysis. Raman spectra of LiTaO3 and (Li,Mg)TaO3 show notable changes over the measured pressure range. Raman peaks centered at 250 cm–1 and 350 cm–1 at ambient pressure merge above 8 GPa, which we associate with the diminishing of difference in distances between Li-O and Ta-O bonds with pressure in both materials. Finally, Raman spectra show significant changes at 28 GPa and 33 GPa for LT and LMT

  20. The {sup 9}Be({sup 8}Li,{sup 9}Be){sup 8}Li elastic-transfer reaction

    SciTech Connect

    Camargo, O.; Guimaraes, V.; Lichtenthaeler, R.; Scarduelli, V.; Kolata, J. J.; Bertulani, C. A.; Amro, H.; Becchetti, F. D.; Jiang Hao; Aguilera, E. F.; Lizcano, D.; Martinez-Quiroz, E.; Garcia, H.

    2008-09-15

    Angular distributions for the {sup 9}Be({sup 8}Li,{sup 9}Be){sup 8}Li elastic-transfer reaction have been measured with a 27-MeV {sup 8}Li radioactive nuclear beam. Spectroscopic factors for the <{sup 9}Be|{sup 8}Li+p> bound system were obtained from the comparison between the experimental differential cross sections and finite-range distorted-wave Born approximation calculations made with the code FRESCO. The spectroscopic factors so obtained are compared with shell-model calculations and other experimental values. Using the present value for the spectroscopic factors, cross sections and reaction rates for the {sup 8}Li(p,{gamma}){sup 9}Be direct proton-capture reaction of astrophysical interest were calculated in the framework of the potential model.