-(void)someFunction
{
    SKEmitterNode *left = [SKEmitterNode nodeWithFileNamed:leftParticle];

        if (oldTimer != nil)
{
    [oldTimer invalidate];
}

oldTimer = [NSTimer scheduledTimerWithTimeInterval:sec target:self selector:@selector(doSomething:) userInfo:[NSArray arrayWithObjects: left, middle, right, nil] repeats:NO];
}

-(void)doSomething:(NSTimer*)timer
{
    [node removeFromParent];
}