Manuale d’uso / di manutenzione del prodotto None del fabbricante Boca Research
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Muon Liquid Handling System User Guide C. Johnson, S.P. Cottrell et al Version 0.2 - 1 -.
Contents 1 Getting Started 3 1.1 Layout of the liquid handling system 3 1.2 Layout of the in situ sample stick 4 1.3 Layout of the pump 4 2 General procedures 6 2.1 Sample loading 6 2.1.1 Loading Vessel 1 6 2.1.2 Loading Vessel 2 6 2.2 Evacuation of the system 6 2.
1 Getting S t arted This manual describes the liquid handling system and the in situ sample cell as use d on the DEVA instrument with the “RF” spect rometer, for either norm al muon spins relaxation or RF resonance experiments.
1.2 Layout of the in situ sample stick The liquid sample stick is designed to fit into the DEVA f low cryostat, details of which can be found in the DEVA manual. It consists of a shapol target cell 30 mm x 30 mm with a mylar window upon which may be mounted an RF coil.
Roughing/ Turbo switch Off/Run switch Pressure reading Turbo control panel Turbo Pump Rotary Pump Figure 2 The lay out of the fr ont panel o n the vacuum pump use d with the muon liqui d handlin g system.
2 General procedures 2.1 Sample loading At this point, the system will be open to the atm osphere, ensure that valve V2 is closed to prevent air cond ensation in the cold trap. 2.1.1 Loading Vessel 1 • Open the tap on the right-hand side of Vessel 1.
2.2.1 Removing air from Vessel 1 Once the system has been pressuris ed, tap A on Vessel 1 can be opened. It is possible to bubbled helium gas through the sample liqui d against the non-retu rn valve, V13. If this is required, first ensure th at valves V 5, V7 and V8 are closed.
2.3 Freeze-Pump-Thaw cycle Using this system it is possible to o perat e freeze-pump-thaw cycles on sam ple liquids held in any of the three vessels. Procedur es appropriate to ea ch vessel are outlined below. 2.3.1 Sample in Vessel 1 • All taps and valves should be closed.
2.3.3 Sample in Vessel 3 • All taps and valves should be closed. • Open valves V2 and V3 along with tap C on Vessel 3 and freeze the sample liquid by slowly raising a dewa r of liquid nitrogen around it. • When it has been determined that the liquid ha s completely frozen switch the pump to roughing mode and open valve V1.
2.4.2 Vessel 3 to sample cell The transfer of liquid from Vessel 3 to the sample cell is brought about by the difference in pressure between that in the Vessel and a vacuum in the cell. However, in order to control the transfer of liquid th e pressure difference shou ld be as small as possible but not so low that the liquid starts to boil.
2.4.4 Recovery of liquid in sample cell to Vessel 1 The liquid in the sample cell cannot be recovered to Vessel 1 using the liquid handling rig as presently configured. 2.4.5 Recovery of liquid in sample cell to Vessel 2 The liquid in the sample cell can be r ecovered to Vessel 2 using the following procedure.
• All the liquid may not return in a single pass and repea ting the evacuation procedure may be required. However, some liquid m ay be present in the system and care should be taken during evacuation that th e trap does not become blocked. The liquid may also be encouraged to leave the sample cell by using a small amount of gas.
3 Example Experiment The paramagnetic signal in liquid n-hexane is difficult to observe because the muonium polarisation is found to decay on a microsecond time scale, which is further reduced by the presence of dissolved oxygen.
0.0 0.5 1.0 1.5 2.0 2.5 3.0 11.0 11.5 12.0 12.5 13.0 13.5 Initial asymmetry (%) Time ( µ s) 0.0 0.5 1.0 1.5 2.0 2.5 3.0 11.0 11.5 12.0 12.5 13.0 Initial asymmetry (%) Time ( µ s) 1.
Un punto importante, dopo l’acquisto del dispositivo (o anche prima di acquisto) è quello di leggere il manuale. Dobbiamo farlo per diversi motivi semplici:
Se non hai ancora comprato il Boca Research None è un buon momento per familiarizzare con i dati di base del prodotto. Prime consultare le pagine iniziali del manuale d’uso, che si trova al di sopra. Dovresti trovare lì i dati tecnici più importanti del Boca Research None - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso Boca Research None imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul Boca Research None ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il Boca Research None, ma non hai ancora letto il manuale d’uso, dovresti farlo per le ragioni sopra descritte. Saprai quindi se hai correttamente usato le funzioni disponibili, e se hai commesso errori che possono ridurre la durata di vita del Boca Research None.
Tuttavia, uno dei ruoli più importanti per l’utente svolti dal manuale d’uso è quello di aiutare a risolvere i problemi con il Boca Research None. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo Boca Research None insieme con le istruzioni su come risolverli. Anche se non si riesci a risolvere il problema, il manuale d’uso ti mostrerà il percorso di ulteriori procedimenti – il contatto con il centro servizio clienti o il servizio più vicino.
