Recently, we succeeded in detecting quark- and meson-effects in the nucleus. These effects were found to depend strongly on the nuclear matter density. So, we are studying the structure of thin neutron- and proton-haloes spreading outside of the nucleus, to study the relation more precisely. For this study, we produce various unstable nuclei using our 5-MV van de Graaff accelerator in Osaka Univ., the cyclotron in RIKEN and the synchrotron in National Institute of Radiological Sciences, and measure reaction cross sections and nuclear moments applying the beta-NMR technique. We explore the nucleon density distributions and shell structure through these measurements. Additionally, we study limitations of the symmetries in the laws of nature, which these phenomena are subject to, through nuclear beta decays and using ultra-cold neutrons. Further, we can measure magnetic fields and electric field gradients inside crystals by observing the beta -NMR (nuclear magnetic resonance) of these unstable nuclear probes and muons implanted directly in various kinds of substances. From these internal fields, we elucidate electron density and its band structure in the crystal. We are collaborating with TRIUMF (Canada) and CIAE (P.R. China).