Acetone is generated upon mesityl oxide (MO) adsorption on TiO2 at 35°C. Water plays an important role in promoting MO decomposition to form acetone. It is suggested that diacetone alcohol plays a role in the transformation of MO to acetone. The thermal reaction of pinacol on TiO2 mainly produces pinacolone at a temperature higher than 100°C. However, acetone is mainly formed in the photocatalytic decomposition of pinacol on TiO2 in O2. Pinacolone is thermally transformed into 2,3‐dimethyl‐1,3‐butadiene in the absence of O2 and into pivalate in the presence of O2. Both the reactions of pinacolone occur above 200°C.

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X-ray photoelectron spectroscopy, reflection–absorption infrared spectroscopy, temperature-programmed reaction/desorption, and density functional theory calculations have been performed to investigate the reaction mechanisms and bonding structures of 3- and 2-bromopropanoic acids on Cu(100) and oxygen-precovered Cu(100). On Cu(100), the bond dissociation of C–Br and O–H in BrCH2CH2COOH is accelerated, occurring at 110 K, as compared to the monofunctional molecules. CH2CH2COOH, CH2CH2COO, and CH3CH2COO from the BrCH2CH2COOH reaction coexist on Cu(100) at 180 K. The CH2CH2COOH is not detected at 250 K, and CH3CH2COO predominates at 320 K. The CH2CH2COO is strongly bonded to the surface via the COO and terminal CH2 groups. In the presence of oxygen atoms on Cu(100), the C–Br scission is suppressed and BrCH2CH2COO is found to be predominant at 150 K. CH2CH2COO begins to form at 200 K and further reacts to produce CH3CH2COO and CH2CHCOO at 320 K through disproportionation or sequential H loss at 2CH2 and hydrogenation at 3CH2. The reaction of CH3CHBrCOOH on Cu(100) also generates CH3CH2COO at 300 K via CH3CHCOOH and CH3CHCOO. The latter species could attach to the surface via the CHCOO or COO group. On O/Cu(100), dissociation of CH3CHBrCOOH forms CH3CHCOO between 200 and 400 K. CH3CHCOO on O/Cu(100) dehydrogenates, at 450 K, into CH2CHCOO. A halogen (Cl and Br) effect is observed in the adsorption structure and reaction path of CH3CHCOO on O/Cu(100).

The methods of QC have significant effects on SMEs’ product quality and may influence the development of the majority of SMEs. In recent years, the principal problems concerning QC for SMEs are that the methods are inefficient and in low degree of application, the workers are not rigorous enough toward self-checking or cross-checking etc. These cause many problems such as the enhanced randomness of product quality problem and the increased working load of quality inspectors, and finally lead to the decrease of enterprise’s quality assurance ability. After analyzing the main problems in SMEs’ QC and their causal factors, the standard method of QC is discussed. Measures such as providing technology support, clarifying responsibilities, establishing the rapid feedback system and improving the visual management of QC are proposed to improve the low application efficiency of QC methods adopted in SMEs and increase the QC effect on the whole process of production.