the small-$\rho$ asymptotics of $$I(\rho)=-\int_{1.1}^{\infty}\frac{\sin(k\rho)}{\rho k^{1.9}\ln k}\,dk$$ is governed by the large-$k$ behavior of the integrand, which gives $I(\rho)\propto \rho^{1.9-2}$ up to a logarithmic factor, and a numerical evaluation supports the asymptotic $$I_{\rm asymp}(\rho)=-\rho^{-0.1}(3.5+0.126\ln\rho)$$ <IMG SRC="https://ilorentz.org/beenakker/MO/loglinearplot.png" WIDTH="400" /> Log-linear plot of $-\rho^{0.1}I(\rho)$ (blue line) and $-\rho^{0.1}I_{\rm asymp}(\rho)$ (orange line) --- UPDATE, following Bazin's recent answer: I have some convergence issues with a numerical evaluation at much smaller $\rho$, but if I can trust the Mathematica output the curve does seem to level off towards an asymptote at zero, as derived by Bazin, possibly as $I(\rho)=-\text{constant}\times(\rho^{0.1}\log\rho)^{-1}$. <IMG SRC="https://ilorentz.org/beenakker/MO/asymptote_2.png" />