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Historically, it was taken for granted that public services would be delivered by a staff of career civil service employees, working within the structure of centralised public agencies budgeted with appropriated funds. Today, none of these are true‐public programmes are more than likely performed by alternative organisations or mechanisms rather than by public agencies (International City Management Association, 1989); and when public agencies are used, they are more likely to be staffed by contingent workers hired through flexible employment mechanisms rather than permanent employees protected by civil service regulations and collective bargaining agreements (Kilbom, 1995).

The aim of this work is to synthesize neopentyl glycol oligoesters based on adipic acid and rapeseed oil (NOAR) which may be used as the renewable and environmentally acceptable base fluids to replace mineral oils in the future.

Oligomeric intermediates were synthesized in the first esterification of neopentyl glycol with adipic acid and characterized by Gas Chromatography-Mass Spectrometer (GC-MS) to calculate the average oligomerisation degree. NOAR were synthesized in the second esterification of oligomeric intermediates with rapeseed oil fatty acid. The effects of average oligomerisation degree on the viscosity, viscosity index, pour point, oxidative stability and biodegradability of NOAR were investigated; the tribological properties and thermal stability of NOAR were evaluated by four-ball tribometer and TGA, respectively.

Results show that with the increase of average oligomerisation degree from 2.10 to 4.34, the viscosity of NOAR increased from 101.1 to 182.0 (mm2/s) at 40°C and 18.3 to 30.1 (mm2/s) at 100°, respectively, and their oxidation stability can be improved as well. The yields of NOAR were 83.3-89.4 per cent, and the evaluated properties were as follows: viscosity index of over 200, pour point of below −43°C, biodegradation rate of more than 96 per cent, maximum non-seizure load (PB value) of 784 N, wear scar diameters of 0.40 mm and thermal decomposition temperature of higher than 300°C.

This work provides a method to synthesize rapeseed oil-based oligoesters which can serve as the renewable and environmentally acceptable base fluids with tunable viscosity by controlling the oligomerisation degree of esterification.

City wall is an important symbol of ancient Chinese cities with unique geographical and cultural characteristics. Thus, the preservation of this historic landmark is considered significantly important. However, numerous residential construction activities and changes in ecological environment have destructed a great portion of the city walls in recent years. This study looks into the preservation of the ancient city walls from the systematic perspective and in line with the actual characteristics of Longdong Region to provide guideline measures for the protection and restoration of such landmark. Cognition and preservation are adopted extensively to investigate the specific situation of and the factors that influence the ancient city walls in this region. Preservation strategies for the city walls, including the “Axis-Point” system, planning control, and authenticity readability, are presented. The ancient city walls in Longdong Region can be preserved by protecting the entire region, the city, and the main wall body. The systematic method and preservation strategies at the “macro perspective,” “medium perspective” and “micro perspective” levels can solve the preservation problems of the ancient city walls in Longdong Region effectively.