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This paper is a tentative endeavor to analyze the functions of interpersonal grammatical metaphor used in Biden’s 2022 State of the Union Address based on the theoretical framework which is composed of interpersonal grammatical metaphor theory and the theory of meta-functions within systematic functional grammar. The interpersonal grammatical metaphor used in this speech is examined from two aspects as metaphors of mood and modality. Quantitative analysis and qualitative analysis are both employed to reveal the linguistic characteristics as well as the interpersonal meaning hidden in the speech, aiming at explore the meta-functions of interpersonal grammatical metaphor so that the understanding of the speech content is deepened. The research has found out that metaphor of modality is the preferred type of interpersonal grammatical metaphor in the chosen linguistic text, which mostly serves to express the speaker’s evaluation of a proposition. The metaphor of mood accounts for a lower proportion, which is mainly used to express the address function. The functions of these two types of interpersonal grammatical metaphor are mainly within the scope of interpersonal meta-function, which relates to interact with others in order to establish and maintain the social relationship. This linguistic research proves the necessity and significance of the existence of grammatical metaphor theory and to some extent enriches the research of interpersonal grammatical metaphor in spoken discourse.

A simple, non-chromatographic and green method based on flow injection UV photochemical or ultrasonic vapor generation atomic fluorescence spectrometry (AFS) was developed for the determination and speciation analysis of mercury. Mercury cold vapor (Hg0) was generated by using only formic acid and UV or ultrasonic irradiation, and was subsequently detected by AFS. Both mercury (Hg2 +) and methyl mercury (MeHg) can be converted to Hg0 for the determination of total mercury with UV irradiation, while only Hg2 + can be reduced to Hg0 with ultrasonic irradiation, thus determining only Hg2 +. Then, the concentration of MeHg can be calculated by subtracting the Hg2 + concentration from the total mercury concentration. The optimal conditions for the best cold vapor generation efficiencies are discussed in detail, together with interference from transition metals. This new speciation analysis not only provides high sensitivity for the determination of mercury species but further eliminates the use of toxic reducing reagents and avoids potential destruction of analyte species that occur in chromatographic separation. Moreover, a simpler and less toxic Hg2 + standard series can be used for the calibration of both Hg2 + and MeHg. The limit of detection is 0.005 or 0.01 μg L− 1 for total mercury with the UV or inorganic mercury with the ultrasonic irradiation, respectively. This method was successfully applied to ultrasensitive mercury speciation analysis of water and biological samples.

A compact and robust OES technique was developed for the sensitive determination of Hg, Fe, Ni, and Co by utilizing photochemical vapor generation and point discharge as the sampling technique and the excitation source, respectively. Mercury cold vapor and the volatile species of Fe, Ni, and Co were generated when standard or sample solutions containing formic acid were exposed to a UV photochemical reactor and subsequently separated from the liquid phase for transport to the microplasma and detection of their atomic emission. Limits of detection (LODs) of 0.10, 10, 0.20, and 4.5 μg L(-1) were obtained for Hg, Fe, Ni and Co, respectively. Compared to conventional microplasma OES, this method not only broadens the scope of elements amenable to determination, but also provides 2- and 7-fold improvement in the LODs for Hg and Ni, respectively. Method validation was demonstrated by analysis of three Certified Reference Materials (GBW08607, DORM-3, and DORM-4) with satisfactory results, and by good spike recoveries (93-111%) from three real water samples.

An in-atomizer atom trapping method based on coating gold nanoparticles onto the inner wall of a quartz tube atomizer was firstly developed and combined with flow injection cold vapor generation for the accurate determination of mercury at low μg L−1 levels by atomic absorption spectrometry. Mercury vapor generated by reducing Hg2+ with hydrochloric acid–tetrahydroborate was efficiently trapped on the surface of gold nanoparticles that were coated on the interior wall of the quartz tube atomizer prior to the determination. In situ desorption and determination of mercury was achieved by increasing the voltage (thus the temperature) to 30 V. The influence of instrumental parameters and experimental conditions on the generation, trapping and desorption of mercury vapor, as well as interference from concomitant elemental ions was investigated. A detection limit of 0.01 μg L−1 was obtained based on a 5.0 mL sampling volume. The precision was better than 4.0% at 0.5 μg L−1. Three spiked water samples and two Certified Reference Materials (dogfish muscle, DORM-4 and human hair powder GBW07601a) were analyzed to validate the accuracy of the proposed method.

An improved hollow fiber supported liquid–liquid–liquid membrane microextraction (HF-LLLMME) method is described for the simultaneous extraction of inorganic and organic mercury species with high efficiency prior to speciation analysis by capillary electrophoresis. The HF-LLLMME was developed by filling cyclohexane and L-cysteine aqueous solution in the pores of the hollow fiber wall and its lumen as organic liquid membrane and acceptor phase, respectively. Inorganic mercury (Hg2+), methylmercury (MeHg), ethylmercury (EtHg) and phenylmercury (PhHg) firstly formed hydrophobic complexes with 1-(2-pyridylazo)-2-naphthol in donor solutions, wherein the hollow fiber was immersed. The complexes were then extracted into the organic liquid membrane and further transferred into the lumen of the hollow fiber to form hydrophilic complexes with L-cysteine. The factors affecting the extraction efficiency were carefully investigated. With the consumption of 50 mL of sample solution, the enrichment factor was 103, 265, 511 and 683 for Hg2+, MeHg, EtHg and PhHg, respectively. The limits of detection were in the range of 0.07–1.0 ng mL−1 (as Hg) with precisions (RSDs, n = 6) ranging from 1.7 to 4.4%. The proposed method was validated by analyzing a certified reference material (DORM-2, dogfish-muscle) and an environmental water sample with satisfactory results.