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Neutron induced reactions on 26Al, 36Cl and 41Ca and their astrophysical implications In this work (n,p) and (n,alpha) reactions on 26Al, 36Cl and 41Ca are studied as a function of the neutron energy. The measurements were performed at the high resolution GELINA time-of-flight facility of the IRMM in Geel, Belgium. Besides the nuclear physics information obtained from the resonance analysis of the reaction cross sections, these reactions are of importance in the understanding of the observed 36S and 26Al solar abundances. In the case of 26Al, the 26Al(n,alpha)23Na cross section up to 45 keV has been determined. Six resonances are observed. For three of them, the total level width and the spin could be calculated. For most of the resonances the obtained resonance parameters are in agreement with previous data. The calculated Maxwellian Averaged Cross Section values (MACS) used in stellar model calculations confirm that 26Al is indeed severely depleted by neutron captures in AGB stars. In the (n,p) and (n,alpha) measurements on 36Cl, eighteen resonances are observed in the energy region up to 250 keV, whereas eight were identified before. Only the lowest energy resonance shows a significant (n,alpha)-contribution of (76+-7)%, which is in perfect agreement with the value reported before. Furthermore, for four resonances, the resonance strength, spin, total and partial width Gamma_p could be determined. They are in good agreement with previous data, but the achieved accuracy is better. The calculated MACS values are used in stellar model calculations to trace the origin of 36S and reveal that the weak component of the s-process occurring in massive stars accounts for almost the entire production of solar 36S. The 41Ca(n,alpha)38Ar measurement is the first ever reported in the resonance region and affects the 36S abundance through 41Ca(n,alpha)38Ar(n,gamma)39Ar(n,alpha)36S. Twelve resonances are observed in the energy region up to 45 keV. For most of them the area, the total width, the spin and a value for Gamma_n/Gamma_p could be determined. After extension of the energy range, with a complementary measurement at the GELINA facility, the calculated MACS values will be used in stellar models.