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Study of HTS Insert Coils for High Field Solenoids
Fermilab is currently working on the development of high field magnet systems for ionization cooling of muon beams. The use of high temperature superconducting materials (HTS) is being considered for these solenoids using Helium refrigeration. Several studies have been performed on insert coils made of BSCCO-2223 tapes and second generation (2G) YBCO coated conductors, which are tested at various temperatures and at external fields of up to 14 T. Critical current (I{sub c}) measurements of YBCO short samples are presented as a function of bending stress, magnetic field and field orientation with respect to the sample surface. An analytical fit of critical current data as a function of field and field orientation is also presented. Results from several single-layer and double-layer pancake coils are also discussed
Verification Testing of MQXFA Nb3Sn Wires Procured Under LARP
The High-Luminosity LHC Accelerator Upgrade Project (AUP) in the U.S. will
construct quadrupole magnets to be delivered to CERN. An initial 3 tons, over
600 km total length of conductor was procured under the LHC Accelerator R&D
Program (LARP) for this project. Programs for quality control(QC) at the
supplier and quality verification (QV) at the laboratories were solidified into
components of the overall quality plan for strand procurement under AUP.
Measurements of the critical current (Ic) and residual resistance ratio (RRR),
and related probes and techniques, are central to the quality plan. Described
below is the verification testing that has taken place at the National High
Magnetic Field Laboratory (NHMFL). Testing challenges are presented by the high
sensitivity of these wires. In addition, new RRR test software was developed to
accommodate challenges presented by meeting international standards with
existing configurations of test strands.Comment: 4 pages, 7 figure
Development and demonstration of next generation technology for Nb_3Sn accelerator magnets with lower cost, improved performance uniformity, and higher operating point in the 12-14 T range
The scope of the proposal outlined in this white paper is the development and
demonstration of the technology needed for next generation of Nb_3Sn
accelerator magnets in the 12-14 T range. The main goal is to cut magnet
cold-mass cost by a factor 2 or higher with respect to the Nb_3Sn magnets
produced by the US Accelerator Upgrade Project (AUP) for the High-Luminosity
Large Hadron Collider (HL-LHC). This goal will be achieved by significant
reduction of labor hours, higher operating point, and improved performance
uniformity. A key factor will be automation that will be achieved through
industry involvement and benefitting from the experience gained in US national
laboratories through the production of the AUP magnets. This partnership will
enable the development of a technology that will be easily transferable to
industry for mid- and large-scale production of Nb_3Sn accelerator magnets in
the 12-14 T range. This step is essential to enable next generation of
colliders such as the FNAL-proposed Muon Collider, FCC and other HEP hadron
colliders.
This is a Directed R&D where direction is given by the field range and
industry involvement for high-automation and industry-ready technology. The
plan includes ten milestones, to be achieved in 6-8 years at the cost of 5-7
$M/year.Comment: White Paper for Snowmass 2022, 8 pages, 2 tables, 1 figur
The “Lazio advice” telemedicine platform. First results of general practitioners’ usage, facilitators and barriers in the local health authority Roma 1
Background: Telemedical approaches represent a valuable tool for the management of coronavirus disease 2019 patients,
allowing daily clinical assessment, monitoring of vital parameters, remote visits, and prescription of treatment or hospital ization in case of clinical worsening. This cross-sectional study aims to evaluate the use, barriers and facilitators of the “Lazio
ADVICE” telemedical platform, a regional system for remote assistance for coronavirus disease 2019 patients at home,
according to General Practitioners and Family Pediatricians of the Local Health Authority Roma 1, during the coronavirus
disease 2019 pandemic.
Methods: An interview-based survey was performed between December 2020 and January 2021. The survey investigated the
demographic information of General Practitioner and Family Pediatricians, the knowledge of the platform, frequency of util ization, usefulness, strengths and weaknesses, and hypothesis of future implementation proposed.
Results: We interviewed 214 physicians and 89 (41.6%) were classified as users and 125 (58.4%) as non-users. Older age
and working in District 1, 14 and 15 (vs. District 13) significantly reduced the probability of using the platform physician.
Among the 89 users, 19 (21.3%) used the platform every day or even several times a day, 40 (44.9%) several times a
week but less than one access per day, 30 (33.7%) used the platform several times a month up to one entry per week.
Most of them (92.3%) consider the platform useful. Barriers were poor integration with software and work routine
(76.4%), and usability issues (53.9%). Among the 125 non-users, 14 (11.2%) didn’t know the existence of the platform,
60 (48.0%) never tried it and 51 (40.8%) tried to use it. Reported reasons for the interruption of use were not very user friendly (45.1%), perceived useless (37.3%), non-optimal functioning (23.5%), and lack of time (19.6%).
Conclusion: The pandemic accelerated the implementation of telemedicine services around Lazio Region, starting a positive
and continuous exchange of experiences, activities and best practices among physicians
A clinical trial of oral hyposensitization in systemic allergy to nickel.
Nickel allergy is the most common contact allergy. Some nickel-sensitive patients present systemic (cutaneous and/or digestive) symptoms related to the ingestion of high nickel-content foods, which significantly improve after a specific low nickel-content diet. The etiopathogenetic role of nickel in the genesis of systemic disorders is, furthermore, demonstrated by the relapse of previous contact lesions, appearance of widespread eczema and generalized urticaria-like lesions after oral nickel challenge test. The aim of this study is to investigate the safety and efficacy of a specific oral hyposensitization to nickel in patients with both local contact disorders and systemic symptoms after the ingestion of nickel-containing foods. Inclusion criteria for the recruitment of these patients were (other than a positive patch test) a benefit higher than 80% from a low nickel-content diet and a positive oral challenge with nickel. Based on the previous experiences, our group adopted a therapeutic protocol by using increasing oral doses of nickel sulfate associated to an elimination diet. Results have been excellent: this treatment has been effective in inducing clinical tolerance to nickel-containing foods, with a low incidence of side effects (gastric pyrosis, itching erythema)
Produzione, qualitĂ e analisi della filiera produttiva del lino da fibra in Italia
Fibre flax (Linum usitatissimum L.) is disappeared from the ltalian crop systems, while the textile industry has reached a leading position. The reintroduction of the crop is than potentially promising but the crop techniques and the production processes have to be set up.
In 12 environments: crop development and growth, cultivar response, straw, fibre and seed yields, and fibre quality were analysed in the 1992-98 period.
The data pointed out crop cycles of 176 and 110 d for the autumn and the spring sowing time respectively, corresponding to 1125 and 990°C d cumulated growing degree. Straw yield at pulling was on average of 6.3 t ha-1, with relevant differences among years and environrnents. Early maturity cultivar yielded more in the less favourable sites. N fertilization was occasionally relevant, and a generally distributions of 60 kg N ha-1 was the more effective. In the Mediterranean environments, with the autumn, sowing flax was more productive and the yield steady. The long fibre ratio was often low (10-13%) and the quality uneven because of the insufficient cleanliness due to retting difficulties. Occasionally, the value of the fibre was affected by the insufficient stem length. In the less dense crop, the seed yield was on average 0.9 t ha-1. Such productions were similar to those assessed for the more dense crop.
In conclusion: because of the complexity of the interactions among the crop growth, the yield, the retting process and the fibre quality flax reintroduction is doubtful. In the production processes retting seems to be the crucial phase.
Il lino da fibra (Linum usitatissimum L.) è da tempo assente negli ordinamenti colturali italiani, mentre è assai importante l'industria di filatura. La reintroduzione della coltura appare quindi potenzialmente promettente, ma richiede la messa a punto dell'agrotecnica e della filiera produttiva.
Nel periodo 1992-1998 in 12 ambienti sono stati esaminati: lo sviluppo e la crescita della coltura, l'adattamento di cultivar, la produzione di paglia, fibra e seme, la resa alla stigliatura, la qualitĂ della fibra.
I dati raccolti evidenziano cicli colturali in media di 176 e 110 d rispettivamente per le semine autunnali (ambienti del centro-sud) e vemino-primaverili; corrispondenti a somme termiche di 1125 e 990°C d. La produzione di paglia alla estirpatura è stata in media di 6.3 t ha-1 con valori assai variabili tra annate e ambienti. Le varietà a ciclo corto sono apparse migliori nelle condizioni difficili. L'effetto della concimazione azotata è apparsa talvolta rilevante e comunque con dosi ottimali prossime a 60 kg ha-1 di N. Negli ambienti del centro-sud le semine autunnali si sono
dimostrate spesso le più interessanti e sicure. La resa in fibra lunga è stata bassa (10-13%) e la qualità variabile per la scarsa pulizia dovuta alle difficoltà di macerazione. La modesta lunghezza tecnica dello stelo sovente riduce il valore del prodotto. In coltura rada, la produzione di seme è variata da 0.5 a 1.5 t ha-1; tali valori non si sono discostati in modo apprezzabile da quelli ottenuti in coltura fitta.
In conclusione, la diffusione del lino appare problematica per le complesse interazioni tra la produzione, il processo di macerazione e la qualitĂ della fibra. Soprattutto la macerazione appare il passaggio chiave
Mass testing of the JUNO experiment 20-inch PMTs readout electronics
The Jiangmen Underground Neutrino Observatory (JUNO) is a multi-purpose,
large size, liquid scintillator experiment under construction in China. JUNO
will perform leading measurements detecting neutrinos from different sources
(reactor, terrestrial and astrophysical neutrinos) covering a wide energy range
(from 200 keV to several GeV). This paper focuses on the design and development
of a test protocol for the 20-inch PMT underwater readout electronics,
performed in parallel to the mass production line. In a time period of about
ten months, a total number of 6950 electronic boards were tested with an
acceptance yield of 99.1%
Implementation and performances of the IPbus protocol for the JUNO Large-PMT readout electronics
The Jiangmen Underground Neutrino Observatory (JUNO) is a large neutrino
detector currently under construction in China. Thanks to the tight
requirements on its optical and radio-purity properties, it will be able to
perform leading measurements detecting terrestrial and astrophysical neutrinos
in a wide energy range from tens of keV to hundreds of MeV. A key requirement
for the success of the experiment is an unprecedented 3% energy resolution,
guaranteed by its large active mass (20 kton) and the use of more than 20,000
20-inch photo-multiplier tubes (PMTs) acquired by high-speed, high-resolution
sampling electronics located very close to the PMTs. As the Front-End and
Read-Out electronics is expected to continuously run underwater for 30 years, a
reliable readout acquisition system capable of handling the timestamped data
stream coming from the Large-PMTs and permitting to simultaneously monitor and
operate remotely the inaccessible electronics had to be developed. In this
contribution, the firmware and hardware implementation of the IPbus based
readout protocol will be presented, together with the performances measured on
final modules during the mass production of the electronics
Validation and integration tests of the JUNO 20-inch PMTs readout electronics
The Jiangmen Underground Neutrino Observatory (JUNO) is a large neutrino
detector currently under construction in China. JUNO will be able to study the
neutrino mass ordering and to perform leading measurements detecting
terrestrial and astrophysical neutrinos in a wide energy range, spanning from
200 keV to several GeV. Given the ambitious physics goals of JUNO, the
electronic system has to meet specific tight requirements, and a thorough
characterization is required. The present paper describes the tests performed
on the readout modules to measure their performances.Comment: 20 pages, 13 figure
Potential of Core-Collapse Supernova Neutrino Detection at JUNO
JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve
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