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Grammar is "a system of rules governing the conventional arrangement and relationship of words in a sentence" (Brown 1994) which can facilitate the acquisition of a foreign language and is conducive for cultivating comprehensive language competence. Most teachers regard grammar as a frame of English learning. The grammar teaching beliefs held by teachers can affect their practical teaching behaviors in class, thus can have different teaching results in the end. Therefore, through quantitative and qualitative research, this paper aims to investigate the present status of grammar beliefs of high school students as well as teachers' beliefs and their grammar teaching behaviors, analyze and compare the similarities and differences between them. The result shows that teachers' grammar teaching has the tendency of communicative teaching while students' grammar beliefs have the characteristic of integration of communicative and traditional grammar teaching. Teachers' grammar teaching behaviors can basically be consistent with their grammar teaching beliefs.

Anisotropy has played a critical role in many material systems, but its controllable creation and modulation have been a long-lasting challenge for the scientific communities. Polarization-addressed anisotropy appears more attractive among all approaches due to its excellent controllability, simplicity, and accuracy, but only a limited number of material systems are applicable for such a concept, which are largely focused on oriented growth. Here, we establish a polarization-dependent anisotropic etching system made of Au@oligomer core–shell nanoparticles (NPs). As the oligomer coatings can be photochemically degraded via two-photon photolithography, the plasmonic near-field enhancement supported by the Au NP cores renders much faster degradation of the oligomer shells along the polarization, resulting in anisotropic Au@oligomer hybrid NPs. Such shape anisotropy leads to polarization-dependent photoluminescence with embedded dyes of methylene blue, which can be used as single-particle-based polarization detector. The oligomer lobes capped at the sides of the Au NP can also function as a protection agent for anisotropic photochemical growth of Au NPs, which evolve into Au nanorods and mushrooms with controlled irradiation time. Such polarization-directed etching of oligomer shells has unique advantages of high local-selectivity, controllability, and versatility for on-chip nanofabrication, which opens many new opportunities for integrated nanophotonic devices.

We utilized the 228Th/228Ra and 234Th/238U disequilibrium methods to estimate the export of particulate organic carbon (POC) from the upper twilight zone in the northern South China Sea during four cruises from August 2009 to May 2011, covering an entire seasonal cycle of spring, summer, autumn, and winter. A significant finding of this study is that 228Th/228Ra disequilibrium method is highly sensitive for tracing POC export in the twilight zone, as demonstrated by the comparison of the "Minimum Detection Limit" (MDL) of various methods. We thus further conclude that 228Th/228Ra disequilibrium is suitable for the research of the twilight zone by comparing the POC export fluxes derived from 228Th/228Ra and 228Ra‐NO3− disequilibrium. The mesopelagic transfer efficiency (Teff), defined as the ratio of POC flux at 500–100 m, varied from 8% to 130%. The Teff derived from >53 μm 234Th (228Th) was higher than that based on 1–53 μm. Large particles were observed to sink rapidly and exit the twilight zone. The Teff was lower at the sampling station influenced by the Kuroshio waters in winter and spring, where the exported organic matter was relatively labile and prone to remineralization in the twilight zone. Conversely, the Teff was relatively higher at other stations, indicating that the exported organic matter was refractory and underwent comparatively less degradation in the twilight zone. Key Points: The mesopelagic transfer efficiency (Teff) was determined to be 8%–130%228Th/228Ra disequilibrium is an extremely sensitive method for tracing particulate organic carbon (POC) export in the twilight zonePOC export fluxes above 500 m derived from 234Th/238U and 228Th/228Ra disequilibria were inconsistent due to the different time scales [ABSTRACT FROM AUTHOR]

Taking the yield and purity of baicalin as evaluation indicators, the acid precipitation method, alkalisoluble acid precipitation method, recrystallization method and pharmacopeia purification method were used to purify baicalin, and the best purification method was determined as alkali-soluble acid precipitation method. Plackett-Burman test was used to obtain the key process parameters in the alkali-soluble acid precipitation method, and the regression model between the key process parameters and the key evaluation indicators was established by the Box-Behnken response surface test, and the design space was obtained and verified. The key parameters obtained by screening were the liquid concentration, alkali solution temperature, alkali solution pH, acid precipitation temperature, and acid precipitation pH. When the yield and purity of baicalin were both greater than 85%, the operating space were; the alkali solution temperature was 40, the pH of alkali solution was 8. 0, the temperature of acid precipitation was 80 °C, the concentration of liquid medicine was 11. 53-14 mg⋅mL-1, and the pH of acid precipitation was 1.17-2.33. The verification results show that the design space was stable and reliable, and it could pro-vide a reference for industrial production of Scutellaria baicalensis extract. [ABSTRACT FROM AUTHOR]