Bruker Corp., a maker of analytical instruments, is demonstrating that not all corporate capital spending is tight, Dow Jones reported. The Billerica-based company logged strong third-quarter results. Chief executive Frank Laukien noted Monday that demand is still softening in some areas but applauded Bruker’s ability to report double-digit organic revenue growth — due partly to “our still very significant backlog.” Third-quarter revenue was $447.8 million, up 7 percent from a year earlier. Net ­income was $39.7 million, compared to $19.8 million a year earlier.