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R-2-(4-hydroxyphenoxy)propionic acid (R-HPPA) is a key intermediate for the synthesis of classic herbicides with high selectivity against grassy weed. The main route for R-HPPA biosynthesis is to hydroxylate the substrate R-2-phenoxypropionic acid (R-PPA) at C-4 position with microbes. In order to provide sufficient R-PPA for the industrial production of R-HPPA, an effective R-PPA synthesis method was established and optimized in this work. The synthesis process mainly consisted of two steps: (1) synthesis of S-2-chloropropionic acid from L-alanine viadiazotization and chlorination reactions; and (2) synthesis of R-PPA from S-2-chloropropionic acid and phenol viaetherification reaction. The optimal reaction conditions were as follows: HCl: NaNO2: KI: L-Ala = 2.0: 1.2: 0.7: 1.0 (in molar), 125 °C reflux for 1.5 h, with KI as catalyst, and KI: S-2-chloropropionic acid: phenol = 0.075: 1.2: 1.0 (in molar). Under these conditions, an improved molar conversion rate (74.9%, calculated in phenol) was achieved. After extraction using anionic exchange resin Amberlite IRA-400 (CI), R-PPA product with a purity of 95.08% was obtained. The purified R-PPA was identified and evaluated in the application of the biotransformative production of R-HPPA. The results indicated that the synthesized R-PPA supported the R-HPPA biosynthesis with a comparable yield as that of the standard R-PPA. The R-PPA synthesis method provided herein exhibited the advantages of low price and easy availability of raw materials, less toxicity of reagents, simple manipulations, and low equipment/instrument requirements.

Abstract: Defining relevant markets is the foundation of establishing main antimonopoly regimes and the key issue in enforcing antimonopoly law, which often reflects the leniency or strictness of enforcement. In the process of defining relevant product market, the main factors to be considered include physical function and use purpose of product, product price, consumers’ preference and substitutable possibility of product supply. In defining relevant geographic market, the main consideration involves transportation cost and product characteristics, product price, consumers’ preference and barriers to market access. On the occasion of forthcoming enforcement of the Antimonopoly Law of China, the enforcement authorities should draw up a specific rule of the definition of relevant markets.

North china has been implementing large-scale coal-to-electricity action, for air pollution reduction and rural household indoor environment improvement. This cause electricity fluctuations and load increase. This paper characterizes patterns of three dominated electric heating equipment in Beijing-Tianjin-Tangshan region (BTT), which are thermal storage electric heating radiators (TSEHRs), air-to-water heat pumps (AWHPs), and low temperature air-to-air heat pumps (AAHPs), and estimate their impact on the power grid system of BTT. Due to physical properties, TSEHRs keep operating as a direct-acting electric heating radiator during the daytime, consequently, caused a high electricity consumption up to 144.3 (kWh/m2); AWHPs had to uninterrupted operate to keep heating each currently in-use room, and electricity consumption was 65.6 (kWh/m2); electricity consumption of AAHPs fell to 29.7 (kWh/m2), benefited from separate installation and intermittent operation. Based on those patterns, the impact on power grid system of large scale adoption in BTT were estimated: daily peak-valley ratios of the typical daily load curve, which respectively turned into 42.5%, 22.4%,21.8% from original 26.5%, and the load increase rates of the original monthly maximum load throughout the year, respectively were 101.5%, 9.0%, 2%.