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The first examples of highly effective Henry reactions between nitroalkanes and aldehydes or trifluoromethyl ketones that proceed under catalyst-free and additive-free conditions, in a recyclable tap-water medium, and at room temperature are reported herein. This process tolerates a broad range of aldehydes and trifluoromethyl ketones to give a series of β-nitroalcohol products in excellent yields. Such products are widely used in the syntheses of pharmaceutical intermediates and natural products. This protocol can be successfully scaled up to a 50 mmol scale without reduction in yield. Tap water from different locations in China exhibited pH values ranging from 7.5 to 8.1, but the varying pH had no effect on the yield and the processes were successfully reproduced. Finally, the tap water was effectively recovered and reused without any post-processing, even when the reaction substrates were different.

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The principles and methods are introduced to quantitatively detect the subsurface defect depth and size by pulse-heating infrared thermography. The subsurface defects in different metal and insulating materials were quantitatively measured by using our home-made pulse-heating infrared thermography non-destructive testing system. From our experimental results, it is shown that accurate information can be obtained during a shortly time after the surface of a target is heated by a thermal pulse. Especially for metals a fast recording of the images is required.As for mild steel, our measurements of defect depth and size were taken within one second after the pulse heating. When the defect diameter is larger than 6mm, the depth and size measurements are in good agreement with the practical values. The depth measuring errors are less than 9. 1% for the range of 1 .1 to 1 .3mm. The sizes can be determined with an accuracy of 10% with 1. 1mm defect depth.Because heat penetration in insulating material is much slower than in metal, the lateral thermal diffusion will affect the experimental results seriously, especially for a small, deep defect. For nylon with defects of 15mm and 8mm at a depth of 1.3mm, the depth measuring errors are 9.1 % and 38.5% respectively. The sizes of defects with diameters of 8mm and 4mm at the depth of 1 .1mm can be measured with 8% and 25% accuracies respectively.

A threshold is added to recognize an input pattern that has too few similarities to be one of the memory patterns. A real-time pattern recognition system based on the improved model is given. The unipolar optical pattern recognition system has all the characteristics of a fully bipolar winner-take-all model and has illumination invariance. A liquid-crystal spatial light modulator is used as a real-time input device, and a mask and a lens array perform the threshold and weighted sums of the input pattern. Some experimental results are also shown.