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Ho capito qual’è il problema. Sono quelle maledette figure che mi danno sempre problemi. Infatti le ho rimosse tutte ed ora ho la mia presentazione.
Molte volte mi da errore perchè mi dice che non trova l’immagine (quando invece l’immagine è nella stessa directory). Può essere che questo è dovuto alla dimensione dell’imagine?
Per esempio se scrivo`
\logo{\includegraphics{logo_LUT.jpg}}
`
Nel file .log leggo:!pdfTeX error: C:\Program Files (x86)\MikTex 2.9\miktex\bin\pdflatex.exe (file
D:/UNIVERSITY/ERASMUS DOCUMENTS/CASE SEMINAR TIME SERIES/Time series Material/l
ogo_LUT.jpg): reading JPEG image failed (no JPEG header found)
==> Fatal error occurred, no output PDF file produced!Come risolvo il problema?
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E guarda questo invece:`
\chapter{The critical magnetic field}Critical current density $f_c=$ limit for resistanceless current in superconductor.
Meissner effect: Resistenceless surface current cancel flux from inside material ($\Phi=Li$). This current we call shielding current $f_L$.
If strength of the external magnetic field increases, the shielding current $f_L$ increases.
Eventually shielding current $f_L$ reaches value equal to critical current density, $f_L$ becomes $=f_C$. Then material loses its superconductivity and flux is no longer cancelled.
Exist a limit $B_C$, critical flux density when supersonductivity is lost. This is all way written in a form of critical magnetic field strength, $H_C=B_C/\mu_0$. People talk about critical magnetic field, and use symbol $H_C$.
In addition to shielding current $f_L$, in superconductor can exist current from external current source. We call this \lq\lq{transport current}\rq\rq $f_T$.
Total current $\overline{f_S}=\overline{f_T}+\overline{f_L}$ must remain below critical current $f_C$ to have material in superconducting state.
`E ora come la mettiamo?
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Insisto sul discorso del rientro a capoverso. Guarda quanto appare brutto questo pezzo di codice se lascio lavorare il latex xome dici tu:`
\section{Temperature dependence of $\lambda$}
At low temperatures $\lambda\approx$costant. Near $T_c$ penetration depth $\lambda$ go to infinite.
\begin{equation}\label{eq_2.3}
\lambda(T)=\frac{\lambda_0}{(1-t^4)^{1/2}}.
\end{equation}Where $\lambda_0=$ penetration depth at $T=0K$
\indent\quad\quad\;\;\;\;\; $t=\frac{T}{T_c}=$ relative temperature.
When $T\into T_c$, then magnetic flux penetrate throughout the sample.
Temperature dependence is very sharp: to obtain $\lambda=1nm$, sample should be only $10^{-7}\%$ below $T_c$.
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E’ orribile e non lo puoi negare!
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Mi sai dire qual’è l’errore qui?`
\begin{equation*}
\begin{aligned}
&\left.\begin{aligned}
&\text{Current in superconductor flow only on the surface.}\\
&\text{Inside the material is no current.}
\end{aligned}
\right\}&
\begin{aligned}\left(
\begin{array}{cc}
&\text{prove in calculation}\\
&\text{using } \nabla\times\overline{B}=\mu_0\overline{f} \text{(2.1)}
\end{array}\right )
\end{aligned}
\end{equation*}
`
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