Performance of Hamamatsu 64-anode photomultipliers for use with wavelength--shifting optical fibres

Hamamatsu R5900-00-M64 and R7600-00-M64 photomultiplier tubes will be used with wavelength--shifting optical fibres to read out scintillator strips in the MINOS near detector. We report on measurements of the gain, efficiency, linearity, crosstalk, and dark noise of 232 of these PMTs, of which 219 met MINOS requirements.Comment: 15 pages, 12 figures. Accepted by Nucl. Inst. Meth.

Evolution of proto-neutron stars with the hadron-quark phase transition

The Poyakov-Nambu-Jona-Lasinio (PNJL) model was developed recently, which includes both the chiral dynamics and (de)confinement effect and gives a good description of lattice QCD data. In this study we use the PNJL model to describe the quark phase, and first use it to study the evolution of proto-neutron star (PNS) with a hadron-quark phase transition. Along the line of a PNS evolution, we take several snapshots of PNS profiles, presenting the fractions of different species, the equations of state (EOS), and the mass-radius relations at different stages. The calculation shows the mixed phase may exist during the whole evolving process, and the onset density of quark phase decreases with the radiation of neutrinos in the heating stage. In the cooling stage, the EOS of the mixed phase softens and the center density increases. In this process a part of nuclear matter transforms to quark matter, which may lead to a PNS collapsing into a black hole.Comment: Accepted/to be published in Physics Lette

Compact on-Chip Temperature Sensors Based on Dielectric-Loaded Plasmonic Waveguide-Ring Resonators

The application of a waveguide-ring resonator based on dielectric-loaded surface plasmon-polariton waveguides as a temperature sensor is demonstrated in this paper and the influence of temperature change to the transmission through the waveguide-ring resonator system is comprehensively analyzed. The results show that the roundtrip phase change in the ring resonator due to the temperature change is the major reason for the transmission variation. The performance of the temperature sensor is also discussed and it is shown that for a waveguide-ring resonator with the resonator radius around 5 μm and waveguide-ring gap of 500 nm which gives a footprint around 140 μm2, the temperature sensitivity at the order of 10−2 K can be achieved with the input power of 100 μW within the measurement sensitivity limit of a practical optical detector

Effects of gaseous NH3 and SO2 on the concentration profiles of PCDD/F in flyash under post-combustion zone conditions

The influence of gaseous ammonia and sulphur dioxide on the formation of 2378-substituted PCDD/F on a reference flyash from a municipal waste incinerator has been investigated using a laboratory scale fixed-bed reactor. The reference flyash samples (BCR-490) was reacted under a simulated flue gas stream at temperatures of 225 and 375 °C for 96 h. The experiments were carried out in two series: first with simulated flue gas alone, and then with injection of NH3 or SO2 gas into the flue gas just before the reactor inlet. It was found that the injection of gaseous ammonia into the flue gas could decrease the concentration of both PCDD and PCDF by 34–75% from the solid phase and by 21–40% from the gas phase. Converting the results to I-TEQ values, it could reduce the total I-TEQ values of PCDD and PCDF in the sum of the flyash and exhaust flue gas by 42–75% and 24–57% respectively. The application of SO2 led to 99% and 93% reductions in the PCDD and PCDF average congener concentrations, respectively in the solid phase. In the gas phase, the total reductions were 89% and 76% for PCDD and PCDF, respectively. Moreover, addition of SO2 reduced the total I-TEQ value of PCDD and PCDF in the flyash and exhaust flue gas together by 60–86% and 72–82% respectively. Sulphur dioxide was more effective than ammonia in suppressing PCDD/F formation in flyash under the conditions investigated

Performance Assessment and Outlook of China’s Emission-Trading Scheme

China overtook the US as the world’s top emitter in 2007, and produced 1.5 times the emissions of the US by 2013 [1]. At present, China’s emissions make up over a quarter of the global total. China is expected to produce three times the emissions of the US by 2030 [2]. Indeed, China’s role and efforts in CO2 reductions matter greatly for the peaking of global emissions, even without further emission leakages to less-developed regions or countries. China recently announced the launch of a nation-wide emission-trading scheme (ETS) starting in 2017 [3] in order to help deliver its emission peak by 2030. A number of climate policies in China are ongoing, and require a full performance review, effective coordination, and appropriate implementation of planning and monitoring measures along with any newly added mechanisms. This paper utilizes the latest energy and emission data to explore the impact of emission trading as a policy driver toward absolute emission and emission intensity changes in China and in its seven provinces or municipalities

Imaging COX-2 expression in cancer using PET/SPECT radioligands: current status and future directions

The role of cyclooxygenase (COX)-2 as a driving force in early tumourigenesis and the current interest in the combination of COX-2 inhibitors with standard therapy in clinical trials creates an urgent need to establish clinically relevant diagnostic tests for COX-2 expression. Molecular imaging using small-molecule probes radiolabelled for both positron emission tomography (PET) and single photon emission computed tomography (SPECT) offers the potential to meet this need, providing a minimally invasive readout for the whole disease burden. This review summarises current approaches to the radiolabelling of small-molecule COX-2 inhibitors and their analogues for PET and SPECT imaging, and gives an overview of their biological evaluation and likely success of clinical application. © 2013 John Wiley & Sons, Ltd

Temporal change in India’s imbalance of carbon emissions embodied in international trade

In India, rapid industrialization and reorganization of the global supply chain are driving economic growth, accompanied by increasing exports and carbon emissions. India is poised to succeed China as the next world manufactory, which will lead to huge emissions in the country. To formulate appropriate emission mitigation measures, it is necessary to further understand the temporal change in India’s emissions at the sectoral level from both the production and consumption perspectives. However, existing studies that have estimated emissions in India have paid less attention to the link among original emitters, final producers and final consumers and to its temporal change. Based on an emission inventory compiled in this study, we trace emission flows from original emitters to final producers and then to final consumers through the international supply chain by using an environmentally extended multi-regional input-output model. This study finds that both production-based and consumption-based emissions in India increased constantly from 2000 to 2014, and production-based emissions had higher growth rates due to the increased coal share. The major receivers of India’s exported emissions were developed countries (e.g., the European Union and the United States), while the main sources of India’s imported emissions were developing countries (e.g., China and Russia). From 2011 to 2014, India’s net exported emissions increased by 29.2% because of the decrease of imported emissions. Moreover, intermediate products (63% and 73.7%) were the major contributors to exported and imported emissions, most of which were embodied in manufacturing products (48.8% and 65.7%, respectively). Therefore, international cooperation to optimize the energy and trade structure and to improve energy efficiency can be effective in mitigating carbon emissions in India