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Differences in synchrotron radiation beamline shielding design between the facilities of 3 GeV class and 8 GeV class are discussed with regard to SLAC SSRL and SPring-8 beamlines. Requirements of beamline shielding as well as the accelerator shielding depend on the stored electron energy, and here some factors in beamline shielding depending on the stored energy in particular, are clarified, namely the effect of build up, the effect of double scattering of photons at branch beamlines, and the spread of gas bremsstrahlung.

Energy Consumption, Efficiency, Conservation, and Greenhouse Gas Mitigation in Japan's Building Sector Authors: Shuzo Murakami (Keio University) Mark D. Levine (Lawrence Berkeley National Laboratory) Hiroshi Yoshino (Tohoku University) Takashi Inoue (Tokyo University of Science) Toshiharu Ikaga (Keio University) Yoshiyuki Shimoda (Osaka University) Shuichi Miura (Tohoku University of A r t & Design) Tomoki Sera (Ministry of Land, Infrastructure and Transport) Masahiro Nishio (Ministry of Economy,Trade and Industry) Yasuhiro Sakamoto (Tokyo Electric Power Company) Wataru Fujisaki (Tokyo Gas) June, 2006 (revised December, 2006) Lawrence Berkeley National Laboratory in collaboration with Japanese institutions identified above

In conventional superconductors, the electron pairing that allows superconductivity is caused by exchange of virtual phonons, which are quanta of lattice vibration. For high-transition-temperature (high-Tc) superconductors, it is far from clear that phonons are involved in the pairing at all. For example, the negligible change in Tc of optimally doped Bi2Sr2CaCu2O8 (Bi2212) upon oxygen isotope substitution (16O to 18O leads to Tc decreasing from 92 to 91 K) has often been taken to mean that phonons play an insignificant role in this material. Here we provide a detailed comparison of the electron dynamics of Bi2212 samples containing different oxygen isotopes, using angle-resolved photoemission spectroscopy. Our data show definite and strong isotope effects. Surprisingly, the effects mainly appear in broad high-energy humps, commonly referred to as "incoherent peaks". As a function of temperature and electron momentum, the magnitude of the isotope effect closely correlates with the superconducting gap - that is, the pair binding energy. We suggest that these results can be explained in a dynamic spin-Peierls picture, where the singlet pairing of electrons and the electron-lattice coupling mutually enhance each other.

Intense pulse electron cyclotron heating (ECH) experiments have been carried out on the MTX tokamak. Rf pulses at 140 GHz with peak power of 1–2 GW and 25 ns pulse length were generated by the ETA‐II/IM FEL and transported quasi‐optically to MTX for O‐mode launch. Because of the intense rf electric fields (∼250 kV/cm), reduction of plasma absorption by nonlinear effects was predicted and several rf beam geometries (kII gradient) were investigated to study their effect on the absorption. Measurements of beam transmission showed increases, compared to low power (2 kW), which agreed with theory to within the data scatter. For these experiments x‐ray, ECE, and Thomson diagnostics showed evidence for localized absorption at the cyclotron resonance and hot electron production. A comparison of these results with calculations from the orbit following code ORPAT will be presented.

Abstract A detailed chemical kinetic model for the mixtures of primary reference fuel (PRF: n -heptane and iso-octane) and toluene has been proposed. This model is divided into three parts; a PRF mechanism [T. Ogura, Y. Sakai, A. Miyoshi, M. Koshi, P. Dagaut, Energy Fuels 21 (2007) 3233–3239], toluene sub-mechanism and cross reactions between PRF and toluene. Toluene sub-mechanism includes the low temperature kinetics relevant to engine conditions. A chemical kinetic mechanism proposed by Pitz et al. [W.J. Pitz, R. Seiser, J.W. Bozzelli, et al., in: Chemical Kinetic Characterization of the Combustion of Toluene, Proceedings of the Second Joint Meeting of the U.S. Sections of the Combustion Institute , 2001] was used as a starting model and modified by updating rate coefficients. Theoretical estimations of rate coefficients were performed for toluene and benzyl radical reactions important at low temperatures. Cross reactions between alkane, alkene, and aromatics were also included in order to account for the acceleration by the addition of toluene into iso-octane recently found in the shock tube study of the ignition delay [Y. Sakai, H. Ozawa, T. Ogura, A. Miyoshi, M. Koshi, W.J. Pitz, Effects of Toluene Addition to Primary Reference Fuel at High Temperature , SAE 2007-01-4104, 2007]. Validations of the model were performed with existing shock tube and flow tube data. The model well predicts the ignition characteristics of PRF/toluene mixtures under the wide range of temperatures (500–1700 K) and pressures (2–50 atm). It is found that reactions of benzyl radical with oxygen molecule determine the reactivity of toluene at low temperature. Although the effect of toluene addition to iso-octane is not fully resolved, the reactions of alkene with benzyl radical have the possibility to account for the kinetic interactions between PRF and toluene.

AbstractA molecular dyad and triad, comprised of a known photosensitizer, BF2‐chelated dipyrromethane (BDP), covalently linked to its structural analog and near‐IR emitting sensitizer, BF2‐chelated tetraarylazadipyrromethane (ADP), have been newly synthesized and the photoinduced energy and electron transfer were examined by femtosecond and nanosecond laser flash photolysis. The structural integrity of the newly synthesized compounds has been established by spectroscopic, electrochemical, and computational methods. The DFT calculations revealed a molecular‐clip‐type structure for the triad, in which the BDP and ADP entities are separated by about 14 Å with a dihedral angle between the fluorophores of around 70°. Differential pulse voltammetry studies have revealed the redox states, allowing estimation of the energies of the charge‐separated states. Such calculations revealed a charge separation from the singlet excited BDP (1BDP*) to ADP (BDP.+‐ADP.−) to be energetically favorable in nonpolar toluene and in polar benzonitrile. In addition, the excitation transfer from the singlet BDP to ADP is also envisioned due to good spectral overlap of the BDP emission and ADP absorption spectra. Femtosecond laser flash photolysis studies provided concrete evidence for the occurrence of energy transfer from 1BDP* to ADP (in benzonitrile and toluene) and electron transfer from BDP to 1ADP* (in benzonitrile, but not in toluene). The kinetic study of energy transfer was measured by monitoring the rise of the ADP emission and revealed fast energy transfer (ca. 1011 s−1) in these molecular systems. The kinetics of electron transfer via 1ADP*, measured by monitoring the decay of the singlet ADP at λ=820 nm, revealed a relatively fast charge‐separation process from BDP to 1ADP*. These findings suggest the potential of the examined ADP–BDP molecules to be efficient photosynthetic antenna and reaction center models.

This dissertation documents the development of a broadband electron spectrometer (ESM) for GeV class Laser Wakefield Accelerators (LWFA), the production of high quality GeV electron beams (e-beams) for the first time in a LWFA by using a capillary discharge guide (CDG), and a statistical analysis of CDG-LWFAs. An ESM specialized for CDG-LWFAs with an unprecedented wide momentum acceptance, from 0.01 to 1.1 GeV in a single shot, has been developed. Simultaneous measurement of e-beam spectra and output laser properties as well as a large angular acceptance (> {+-} 10 mrad) were realized by employing a slitless scheme. A scintillating screen (LANEX Fast back, LANEX-FB)--camera system allowed faster than 1 Hz operation and evaluation of the spatial properties of e-beams. The design provided sufficient resolution for the whole range of the ESM (below 5% for beams with 2 mrad divergence). The calibration between light yield from LANEX-FB and total charge, and a study on the electron energy dependence (0.071 to 1.23 GeV) of LANEX-FB were performed at the Advanced light source (ALS), Lawrence Berkeley National Laboratory (LBNL). Using this calibration data, the developed ESM provided a charge measurement as well. The production of high quality electron beams up to 1 GeV more » from a centimeter-scale accelerator was demonstrated. The experiment used a 310 {micro}m diameter gas-filled capillary discharge waveguide that channeled relativistically-intense laser pulses (42 TW, 4.5 x 10{sup 18} W/cm{sup 2}) over 3.3 centimeters of sufficiently low density ({approx_equal} 4.3 x 10{sup 18}/cm{sup 3}) plasma. Also demonstrated was stable self-injection and acceleration at a beam energy of {approx_equal} 0.5 GeV by using a 225 {micro}m diameter capillary. Relativistically-intense laser pulses (12 TW, 1.3 x 10{sup 18}W/cm{sup 2}) were guided over 3.3 centimeters of low density ({approx_equal} 3.5 x 10{sup 18}/cm{sup 3}) plasma in this experiment. A statistical analysis of the CDG-LWFAs performance was carried out. By taking advantage of the high repetition rate experimental system, several thousands of shots were taken in a broad range of the laser and plasma parameters. An analysis program was developed to sort and select the data by specified parameters, and then to evaluate performance statistically. The analysis suggested that the generation of GeV-level beams comes from a highly unstable and regime. By having the plasma density slightly above the threshold density for self injection, (1) the longest dephasing length possible was provided, which led to the generation of high energy e-beams, and (2) the number of electrons injected into the wakefield was kept small, which led to the generation of high quality (low energy spread) e-beams by minimizing the beam loading effect on the wake. The analysis of the stable half-GeV beam regime showed the requirements for stable self injection and acceleration. A small change of discharge delay t{sub dsc}, and input energy E{sub in}, significantly affected performance. The statistical analysis provided information for future optimization, and suggested possible schemes for improvement of the stability and higher quality beam generation. A CDG-LWFA is envisioned as a construction block for the next generation accelerator, enabling significant cost and size reductions. « less

The Lancet Countdown : le suivi des progrès en matière de santé et de changement climatique est une collaboration de recherche internationale et multidisciplinaire entre des établissements universitaires et des praticiens du monde entier. Il fait suite aux travaux de la Commission Lancet de 2015, qui a conclu que la réponse au changement climatique pourrait être « la plus grande opportunité de santé mondiale du XXIe siècle ». Le compte à rebours du Lancet vise à suivre les impacts sur la santé des risques climatiques ; la résilience et l'adaptation en matière de santé ; les co-bénéfices pour la santé de l'atténuation du changement climatique ; l'économie et la finance ; et l'engagement politique et plus large. Ces domaines d'intervention forment les cinq groupes de travail thématiques du Lancet Countdown et représentent différents aspects de l'association complexe entre la santé et le changement climatique. Ces groupes thématiques fourniront des indicateurs pour une vue d'ensemble mondiale de la santé et du changement climatique ; des études de cas nationales mettant en évidence les pays qui ouvrent la voie ou vont à l'encontre de la tendance ; et un engagement avec un éventail de parties prenantes. Le compte à rebours du Lancet vise finalement à rendre compte chaque année d'une série d'indicateurs dans ces cinq groupes de travail. Ce document décrit les indicateurs potentiels et les domaines d'indicateurs à suivre par la collaboration, avec des suggestions sur les méthodologies et les ensembles de données disponibles pour atteindre cet objectif. Les domaines d'indicateurs proposés doivent être affinés et marquent le début d'un processus de consultation en cours - de novembre 2016 au début de 2017 - pour développer ces domaines, identifier les domaines clés non couverts actuellement et modifier les indicateurs si nécessaire. Cette collaboration cherchera activement à s'engager dans les processus de suivi existants, tels que les objectifs de développement durable des Nations Unies et les profils de pays de l'OMS en matière de climat et de santé. Les indicateurs évolueront également au fil du temps grâce à une collaboration continue avec des experts et un éventail de parties prenantes, et dépendront de l'émergence de nouvelles preuves et connaissances. Au cours de ses travaux, le Lancet Countdown adoptera un processus collaboratif et itératif, qui vise à compléter les initiatives existantes, à accueillir l'engagement avec de nouveaux partenaires et à être ouvert au développement de nouveaux projets de recherche sur la santé et le changement climatique. The Lancet Countdown: tracking progress on health and climate change es una colaboración de investigación internacional y multidisciplinaria entre instituciones académicas y profesionales de todo el mundo. Sigue el trabajo de la Comisión Lancet de 2015, que concluyó que la respuesta al cambio climático podría ser "la mayor oportunidad de salud global del siglo XXI". The Lancet Countdown tiene como objetivo realizar un seguimiento de los impactos en la salud de los peligros climáticos; la resiliencia y la adaptación a la salud; los beneficios colaterales para la salud de la mitigación del cambio climático; la economía y las finanzas; y el compromiso político y más amplio. Estas áreas de enfoque forman los cinco grupos de trabajo temáticos de The Lancet Countdown y representan diferentes aspectos de la compleja asociación entre la salud y el cambio climático. Estos grupos temáticos proporcionarán indicadores para una visión global de la salud y el cambio climático; estudios de casos nacionales que destacan a los países que lideran el camino o van en contra de la tendencia; y el compromiso con una variedad de partes interesadas. En última instancia, The Lancet Countdown tiene como objetivo informar anualmente sobre una serie de indicadores en estos cinco grupos de trabajo. Este documento describe los posibles indicadores y dominios de indicadores a ser rastreados por la colaboración, con sugerencias sobre las metodologías y conjuntos de datos disponibles para lograr este fin. Los dominios de indicadores propuestos requieren un mayor refinamiento y marcan el comienzo de un proceso de consulta continuo, desde noviembre de 2016 hasta principios de 2017, para desarrollar estos dominios, identificar áreas clave que actualmente no están cubiertas y cambiar los indicadores cuando sea necesario. Esta colaboración buscará activamente involucrarse con los procesos de monitoreo existentes, como los Objetivos de Desarrollo Sostenible de la ONU y LOS perfiles climáticos y de salud de los países de la OMS. Los indicadores también evolucionarán con el tiempo a través de la colaboración continua con expertos y una variedad de partes interesadas, y dependerán de la aparición de nuevas pruebas y conocimientos. Durante el transcurso de su trabajo, The Lancet Countdown adoptará un proceso colaborativo e iterativo, que tiene como objetivo complementar las iniciativas existentes, dar la bienvenida al compromiso con nuevos socios y estar abierto al desarrollo de nuevos proyectos de investigación sobre salud y cambio climático. The Lancet Countdown: tracking progress on health and climate change is an international, multidisciplinary research collaboration between academic institutions and practitioners across the world. It follows on from the work of the 2015 Lancet Commission, which concluded that the response to climate change could be "the greatest global health opportunity of the 21st century". The Lancet Countdown aims to track the health impacts of climate hazards; health resilience and adaptation; health co-benefits of climate change mitigation; economics and finance; and political and broader engagement. These focus areas form the five thematic working groups of the Lancet Countdown and represent different aspects of the complex association between health and climate change. These thematic groups will provide indicators for a global overview of health and climate change; national case studies highlighting countries leading the way or going against the trend; and engagement with a range of stakeholders. The Lancet Countdown ultimately aims to report annually on a series of indicators across these five working groups. This paper outlines the potential indicators and indicator domains to be tracked by the collaboration, with suggestions on the methodologies and datasets available to achieve this end. The proposed indicator domains require further refinement, and mark the beginning of an ongoing consultation process-from November, 2016 to early 2017-to develop these domains, identify key areas not currently covered, and change indicators where necessary. This collaboration will actively seek to engage with existing monitoring processes, such as the UN Sustainable Development Goals and WHO's climate and health country profiles. The indicators will also evolve over time through ongoing collaboration with experts and a range of stakeholders, and be dependent on the emergence of new evidence and knowledge. During the course of its work, the Lancet Countdown will adopt a collaborative and iterative process, which aims to complement existing initiatives, welcome engagement with new partners, and be open to developing new research projects on health and climate change. العد التنازلي لمجلة لانسيت: تتبع التقدم المحرز في مجال الصحة وتغير المناخ هو تعاون بحثي دولي متعدد التخصصات بين المؤسسات الأكاديمية والممارسين في جميع أنحاء العالم. ويتبع ذلك عمل لجنة لانسيت لعام 2015، التي خلصت إلى أن الاستجابة لتغير المناخ يمكن أن تكون "أعظم فرصة صحية عالمية في القرن الحادي والعشرين". يهدف العد التنازلي لمجلة لانسيت إلى تتبع الآثار الصحية للمخاطر المناخية ؛ والمرونة الصحية والتكيف ؛ والفوائد الصحية المشتركة للتخفيف من آثار تغير المناخ ؛ والاقتصاد والتمويل ؛ والمشاركة السياسية والأوسع نطاقًا. تشكل مجالات التركيز هذه مجموعات العمل المواضيعية الخمسة للعد التنازلي لمجلة لانسيت وتمثل جوانب مختلفة من الارتباط المعقد بين الصحة وتغير المناخ. وستوفر هذه المجموعات المواضيعية مؤشرات لإلقاء نظرة عامة عالمية على الصحة وتغير المناخ ؛ ودراسات حالة وطنية تسلط الضوء على البلدان التي تقود الطريق أو تسير عكس الاتجاه ؛ والمشاركة مع مجموعة من أصحاب المصلحة. يهدف العد التنازلي لمجلة لانسيت في نهاية المطاف إلى تقديم تقرير سنوي عن سلسلة من المؤشرات عبر مجموعات العمل الخمس هذه. تحدد هذه الورقة المؤشرات المحتملة ومجالات المؤشرات التي سيتم تتبعها من خلال التعاون، مع اقتراحات حول المنهجيات ومجموعات البيانات المتاحة لتحقيق هذه الغاية. تتطلب مجالات المؤشرات المقترحة مزيدًا من التنقيح، وتمثل بداية عملية تشاور مستمرة - من نوفمبر 2016 إلى أوائل 2017 - لتطوير هذه المجالات، وتحديد المجالات الرئيسية غير المشمولة حاليًا، وتغيير المؤشرات عند الضرورة. سيسعى هذا التعاون بنشاط إلى المشاركة في عمليات الرصد القائمة، مثل أهداف الأمم المتحدة للتنمية المستدامة والملامح القطرية للمناخ والصحة لمنظمة الصحة العالمية. ستتطور المؤشرات أيضًا بمرور الوقت من خلال التعاون المستمر مع الخبراء ومجموعة من أصحاب المصلحة، وستعتمد على ظهور أدلة ومعارف جديدة. خلال عملها، سيعتمد العد التنازلي لمجلة لانسيت عملية تعاونية وتكرارية، تهدف إلى استكمال المبادرات الحالية، والترحيب بالمشاركة مع شركاء جدد، والانفتاح على تطوير مشاريع بحثية جديدة حول الصحة وتغير المناخ.