44 research outputs found
Coal in the 21st Century: a climate of change and uncertainty
Coal presents a particular set of challenges when balancing energy policy goals. Despite presenting viable solutions to the problems of energy security and global energy poverty, coal struggles, given its greenhouse-gas drawbacks, in a world of increasingly harmful climate change. Notwithstanding the harm caused to the environment, coal remains an expanding low-price route to meeting local energy needs. It is forecasted to remain a major global resource for the foreseeable future. In the short term it is predicted to have a 26% share of the global energy mix. Recent years have witnessed severe deviations from previously stable trends in coal markets and policy dynamics. According to the predictions by the International Energy Agency (IEA), a variety of factors ranging from the planned phase-out of coal in countries such as Denmark, France and the UK, to changes in policy in China and import-dependency in India, and demand drop in the US have together resulted in the largest decline in coal production in 2015 since 1971 (IEA, Coal Information, 2016). This paper seeks to outline basic coal facts, recent market trends and directions globally and provides an overview of issues shaping the future of coal in the twenty-first century. This paper seeks to outline basic coal facts, recent market trends and directions globally and provide an overview of issues shaping the future of coal in the 21st century
Observation of Single Top Quark Production and Measurement of |Vtb| with CDF
Submitted to Phys. Rev. DWe report the observation of electroweak single top quark production in 3.2 fb-1 of ppbar collision data collected by the Collider Detector at Fermilab at sqrt{s}=1.96 TeV. Candidate events in the W+jets topology with a leptonically decaying W boson are classified as signal-like by four parallel analyses based on likelihood functions, matrix elements, neural networks, and boosted decision trees. These results are combined using a super discriminant analysis based on genetically evolved neural networks in order to improve the sensitivity. This combined result is further combined with that of a search for a single top quark signal in an orthogonal sample of events with missing transverse energy plus jets and no charged lepton. We observe a signal consistent with the standard model prediction but inconsistent with the background-only model by 5.0 standard deviations, with a median expected sensitivity in excess of 5.9 standard deviations. We measure a production cross section of 2.3+0.6-0.5(stat+sys) pb, extract the CKM matrix element value |Vtb|=0.91+0.11-0.11 (stat+sys)+-0.07(theory), and set a lower limit |Vtb|>0.71 at the 95% confidence level, assuming m_t=175 GeVc^2.We report the observation of electroweak single top quark production in 3.2 fb-1 of pp̅ collision data collected by the Collider Detector at Fermilab at √s=1.96 TeV. Candidate events in the W+jets topology with a leptonically decaying W boson are classified as signal-like by four parallel analyses based on likelihood functions, matrix elements, neural networks, and boosted decision trees. These results are combined using a super discriminant analysis based on genetically evolved neural networks in order to improve the sensitivity. This combined result is further combined with that of a search for a single top quark signal in an orthogonal sample of events with missing transverse energy plus jets and no charged lepton. We observe a signal consistent with the standard model prediction but inconsistent with the background-only model by 5.0 standard deviations, with a median expected sensitivity in excess of 5.9 standard deviations. We measure a production cross section of 2.3-0.5+0.6(stat+sys) pb, extract the value of the Cabibbo-Kobayashi-Maskawa matrix element |Vtb|=0.91-0.11+0.11(stat+sys)±0.07 (theory), and set a lower limit |Vtb|>0.71 at the 95% C.L., assuming mt=175 GeV/c2.Peer reviewe
Ozonation of refractory chemicals in leachate with hydrogen peroxide
Nearly 97% of organic chemicals in Hong Kong leachate could be effectively removed by the UASB(upflow anaerobic sludge blanket) process followed by the fenton coagulation. The COD of leachate was lowered from an average of 12900 mg/L to 1440 mg/L after the UASB treatment, and was further lowered to 394 mg/L after the fenton coagulation. The remaining refractory residues could be further removed by ozonation with the addition of H2O2. The ozonation for the supernatant of the fenton coagulation was most effective at pH 7-8, with the addition of 300 mg/L of H2O2, and 30 min of reaction. The final effluent contained only 85 mg/L of COD and 10 mg/L of BOD5. On the other hand, direct ozonation of UASB effluent lowered the COD to 905 mg/L and BOD5 to 103 mg/L. Ozonation improved the biodegradability of the organic residues, and also converted part of organic-N in the leachate into NH3-N and NO-3-N.link_to_subscribed_fulltex
Strengthening Support to Victims of Domestic Violence: A Coordinated Community and Criminal Justice Response (from UK to HK)
Praktische Umsetzung der Bauartzulassung - Voraussetzungen fuer die Pruefung von Verfahrenstechnik und Eignung von Bodenbehandlungsanlagen Schlussbericht
Duration and scope of immission permitting are viewed by investors and politicians as an obstacle for investments. Acceleration and deregulation of permitting are essential to strengthen the economic power of Germany. Even a short term use of soil treatment facilities is often impossible due to the time consuming process of immission permitting. A preliminary study performed in 1993 proved the suitability of a design approval as a simplifying and accelerating tool. The presented research report shows the necessary prerequisites to put the theory into practice. As a basic tool an inspection program has been developed for soil treatment facilities. This inspection program is the framework for the evaluation of all types of processing facilities. It simplifies and accelerates the control on the basis of legal requirements. Three soil treatment facilities were taken as examples to examine the checking procedure. It could be proved that this kind of design approval is an appropriate tool to unify the permitting procedure in Germany. The pertinent agencies are relieved of the processing part of the inspection and they receive all relevant data necessary for inspection. The facility owner is gaining certainty regarding planning and investment which will positively effect the treatment industry. (orig.)SIGLEAvailable from TIB Hannover: RN 8908(98-031) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekUmweltbundesamt, Berlin (Germany); Bundesministerium fuer Umwelt, Naturschutz und Reaktorsicherheit, Bonn (Germany)DEGerman