A spark-resistant bulk-micromegas chamber for high-rate applications Alexopoulos, T.; Burnens, J.; de Oliveira, R. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
06/2011, Letnik:
640, Številka:
1
Journal Article
Recenzirano
Odprti dostop
We report on the design and performance of a spark-resistant bulk-micromegas chamber. The principle of this design lends itself to the construction of large-area muon chambers for the upgrade of the ...detectors at the Large Hadron Collider at CERN for luminosities in excess of 10
34
cm
−2
s
−1 or other high-rate applications.
The steadily increasing luminosity of the LHC requires an upgrade with high-rate and high-resolution detector technology for the inner end cap of the ATLAS muon spectrometer: the New Small Wheels ...(NSW). In order to achieve the goal of precision tracking at a hit rate of about 15 kHz/cm2 at the inner radius of the NSW, large area Micromegas quadruplets with 100µm spatial resolution per plane have been produced. IRFU, from the CEA research center of Saclay, is responsible for the production and validation of LM1 Micromegas modules. The construction, production, qualification and validation of the largest Micromegas detectors ever built are reported here. Performance results under cosmic muon characterization will also be discussed.
In the past years, drift chambers with thin-wall tubes (straws) operating in high vacuum (∼10−5 mb) has become to be used in experimental studies of rare decays. Any drift tube of the operating ...chamber may suffer a mechanical or electrical damage and a subsequent leak. The complete failure of the tube is not excluded either. To protect the chambers against the above damage, we have developed and tested a relatively simple protection system based on uniquely designed energy-independent devices. If air-tightness is broken and gas starts leaking from the tube into the vacuum, they automatically cut off the gas flow on both ends of the damaged tube and disconnect it from the gas supply.
•The work can be used for protection the straw drift chamber in vacuum from vacuum penetration.
By three-dimensional modeling, the local heat transfer in the combustion chamber of a traditional diesel is compared with that in a promising hydrogen diesel, which is based on the direct injection ...of gaseous hydrogen. The local heat transfer in the combustion chamber of a hydrogen diesel is analyzed, because it must be taken into account in the conversion of mass-produced diesel engines.
Abstract
Summary. Nitric oxides are the only components from the harmful ones limited by the legislation found in the exhaust gases of the hydrogen engine. For the purpose of their minimization and ...prevention of the anomaly burning processes as well (detonation combustion, early ignition, back fire), the use of the leaked hydrogen-air mixture is offered. The influence of the exhaust gas recirculation (EGR) on the intra-cylindric processes, namely on formation of nitric oxides in the hydrogen engine is studied for the first time experimentally and with the help of the mathematical model based on the three-dimensional non-stationary equations of type of Navier-Stokes. The results obtained for the wide ranges of variation of the advance angle of ignition, excess air ratio and rate of EGR confirm that at successful combination of these controllable parameters the problem of minimization of nitric oxides exhausted by the hydrogen engine is removed.
Georgia at the crossroads Glonti, Georgi
Demokratizatsiya (Washington, D.C.),
10/2000, Letnik:
8, Številka:
4
Journal Article
Recenzirano
Georgia has entered the new millennium as a politically and economically unstable country that has lost control of one-third of its territory. Many Georgian politicians, analysts and scholars have ...tried to understand the reasons for Georgia's unsuccessful transition to independence and democracy and to find a way out of the difficult political and economic situation.
The steadily increasing luminosity of the LHC requires an upgrade with high-rate and high-resolution detector technology for the inner end cap of the ATLAS muon spectrometer: the New Small Wheels ...(NSW). In order to achieve the goal of precision tracking at a hit rate of about 15 kHz/cm\(^2\) at the inner radius of the NSW, large area Micromegas quadruplets with 100\,\microns spatial resolution per plane have been produced. % IRFU, from the CEA research center of Saclay, is responsible for the production and validation of LM1 Micromegas modules. The construction, production, qualification and validation of the largest Micromegas detectors ever built are reported here. Performance results under cosmic muon characterisation will also be discussed.
The aim of the work was to study the effect of metabolic triad with different mechanisms of acting--high-dose Glucose-Insulin-Potassium--25% polarizing solution (25% glucose, 50 IU soluble insulin ...and 4% 144 ml KCL-GIK), mildronat, preductal MR on the functional condition of heart during the acute myocardial infarction. 20 patients from the main group and 20 from the control one have been under the study. Patients with diabetes and heavy forms of heart failure (killip class>2) were not included in the study. Evaluation of the functional condition of heart was based on ECG and echocardiography data received before and after the treatment. It was determined that the frequency of the rhythm disorder decreases in the conditions of metabolic triad as well as during the thrombolitic reperfusion. Average period of time for normalization of S-T segment elevation made up 5.4+/-1.8 days and 7.3+/-1.2 days in case of the control group. The received data make it relevant to include the complex metabolic triad for preventive purpose during the complications followed after the acute myocardial infarction.
We report on the design and performance of a spark-resistant bulk-micromegas chamber. The principle of this design lends itself to the construction of large-area muon chambers for the upgrade of the ...detectors at the Large Hadron Collider at CERN for luminosities in excess of 10**34/cm2/s or other high-rate applications.
Abstract
Our aim was to describe the research practices of doctoral students facing a dilemma to research integrity and to assess the impact of inappropriate research environments, i.e. exposure to ...(a) a post-doctoral researcher who committed a Detrimental Research Practice (DRP) in a similar situation and (b) a supervisor who did not oppose the DRP. We conducted two 2-arm, parallel-group randomized controlled trials. We created 10 vignettes describing a realistic dilemma with two alternative courses of action (good practice versus DRP). 630 PhD students were randomized through an online system to a vignette (a) with (n = 151) or without (n = 164) exposure to a post-doctoral researcher; (b) with (n = 155) or without (n = 160) exposure to a supervisor. The primary outcome was a score from − 5 to + 5, where positive scores indicated the choice of DRP and negative scores indicated good practice. Overall, 37% of unexposed participants chose to commit DRP with important variation across vignettes (minimum 10%; maximum 66%). The mean difference 95%CI was 0.17 − 0.65 to 0.99;, p = 0.65 when exposed to the post-doctoral researcher, and 0.79 − 0.38; 1.94, p = 0.16, when exposed to the supervisor. In conclusion, we did not find evidence of an impact of postdoctoral researchers and supervisors on student research practices.
Trial registration:
NCT04263805, NCT04263506 (registration date 11 February 2020).
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