This research investigates teachers' directive speech act in Arabic Language Teaching. The research was applied through pragmatic approach using the theory of Bach and Harnish's speech act and Yule's speech act strategy. The research instrument is in the form of teachers' speech containing directive meaning. Based on the analysis, it can be concluded that: (1) first, the category of teacher's directive speech act in Arabic language teaching at MAN 1 Jombang involves requesting, advising, commanding, challenging, inviting, daring, and entreating directive speech acts, (2) the speech acts were delivered in directive or underactive with various motives. The results are expected to be useful to be referred in using directive speech acts whether its category or strategy in Arabic language learning. Thus, the communication between teachers and students can be more interactive and meaningful. Therefore, this research is needed to conduct.Keywords: directive speech act, category, strategy, teachers, Arabic language Abstrak Penelitian ini mengkaji tindak tutur direktif guru dalam pembelajaran bahasa Arab. Penelitian ini menggunakan pendekatan pragmatik yaitu teori tindak tutur Bach dan Harnish dan strategi tindak tutur Yule. Data penelitian ini berupa tuturan guru bahasa Arab yang mengandung makna direktif. Berdasarkan hasil analisis data disimpulkan sebagai berikut. Pertama, Kategori TTD guru dalam pembelajaran bahasa Arab di MAN 1 Jombang meliputi tindak tutur requestives meminta, requestives mendoa, requestives mengajak, questions bertanya, questions menyelidik, requirements memerintah, requirements mengarahkan, prohibitives melarang, permissives membolehkan, advisories menyarankan, dan advisories mendorong. Kedua, TTD tersebut disampaikan baik secara langsung dan tidak langsung dengan berbagai modus. Hasil penelitian tersebut diharapkan dapat digunakan sebagai rujukan dalam memilih dan mengunakan TTD baik kategori maupun strateginya dalam pembelajaran bahasa Arab. Dengan demikian, komunikasi antara guru dan siswa lebih interaktif dan bermakna. Oleh karena itu perlu dilakukan penelitian TTD bahasa Arab siswa terhadap guru dan TTD bahasa Arab siswa kepada siswa.

ZnO is the most widely used for photocatalytic application among various semiconductor materials. The photocatalytic performance of ZnO can be enhanced by doping with other materials. In this study, ZnO-SiO2 nanocomposites have been successfully fabricated by gas-phase method via spray pyrolysis. The effect of temperature of spray tubular furnace reactor ranging from 300 to 600 °C on the photocatalytic activity of ZnO-SiO2 nanocomposites were investigated. Colloidal SiO2 with concentration at 1 %wt was used as dopant to ZnO particles. The pristine ZnO was also synthesized at temperature of 400 °C for comparable. Zinc acetate and water glass were used as the precursors for fabrication ZnO-SiO2 nanocomposites. At first, the water glass was synthesized by sol-gel method to produce colloidal SiO2 nanoparticles and then mixed with zinc acetate before subjecting to the spray reactor. The produced nanocomposite materials were collected by an electrostatic precipitator. Scanning electron microscopy and energy-dispersive X-ray (SEM-EDX), X-ray diffraction (XRD), and Fourier-transform infrared (FTIR) were used for characterization the products. While UV-Vis spectrometry was used to measure the concentration of methylene blue (MB) before and after irradiations. SEM images indicated that the morphology of particles was as sphere-like structures with interwoven nanoplate and the agglomeration of particles can be suppressed by adding SiO2. The average particle size of the produced nanocomposite decreased with increasing synthesis temperature. XRD analysis also confirmed that the crystallite size increased with increasing temperature. Finally, the photocatalytic activity of the ZnO-SiO2 nanocomposites were calculated by evaluating the methylene blue degradation aqueous solution under UV and sunlight irradiations. MB degradation efficiency under UV light was much lower than that of under sunlight irradiation. It also showed that the best photocatalytic performance reached 96 % when the synthesis temperature was set as high as 400 °C with SiO2 concentration at 1 %wt under sunlight irradiation.

Creating hollow structures is one strategy for tuning the optical properties of materials. The current study aimed to increase the optical transmittance of silica (SiO 2 ) particles. To this end, hexagonal-shaped hollow silica plate (HHSP) particles were synthesized from tetraethyl orthosilicate (TEOS) and zinc oxide (ZnO) template particles, using a microwave-assisted hydrothermal method. The size and shell thickness of the HHSP particles could be adjusted by using different TEOS/ZnO molar ratios and different ZnO template sizes, respectively. The optical transmittance of the HHSP particles depended on the shell thickness and particle size. The highest transmittance was 99% in the ultraviolet and visible region (300-800 nm) and was exhibited by HHSP particles with the thinnest shell thickness of 6.3 nm. This transmittance was higher than that exhibited by spherical hollow silica particles with a similar shell thickness. This suggested morphologydependent transmittance for the semiconducting material. These preliminary results illustrate the promising features of the HHSP particles and suggest their potential application in future transparent devices.

<p>Penelitian ini bertujuan untuk mendeskripsikan tindak tutur direktif dalam pembelajaran daring di prodi Pendidikan Bahasa Indonesia. Pendekatan penelitian ini adalah pendekatan kualitatif. Sumber data dalaam penelitian adalah tuturan guru dalam pembelajaran daring di program studi pendidikan Bahasa Indonesia. Data dalam penelitian ini adalah tuturan guru yang mengandung tindak tutur direktif yang  berupa kata-kata yang dituturkan secara langsung oleh pengajar saat proses pembelajaran. Pada peneitian ini teknik pengumpulan data yang digunakan adalah teknik sadap dan teknik catat analisis. Hasil penelitian ini menunjukkan bahwa terdapat lima jenis tindak tutur direktif dalam pembelajaran yakni memesan (<em>ordering</em>), memerintah (<em>commanding</em>), memohon (<em>requesting</em>), menasihati (<em>advising</em>), dan merekomendasi (<em>recommending</em>).</p>

No abstract

More than 58 million metric tonnes of oranges were produced in 2021, and the peels, which account for around one-fifth of the fruit weight, are often discarded as waste in the orange juice industry. Orange pomace and peels as wastes are used as a sustainable raw material to make valuable products for nutraceuticals. The orange peels and pomace contain pectin, phenolics, and limonene, which have been linked to various health benefits. Various green extraction methods, including supercritical carbon dioxide (ScCO2) extraction, subcritical water extraction (SWE), ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE), are applied to valorize the orange peels and pomace. Therefore, this short review will give insight into the valorization of orange peels/pomace extraction using different extraction methods for health and wellness. This review extracts information from articles written in English and published from 2004 to 2022. The review also discusses orange production, bioactive compounds in orange peels/pomaces, green extractions, and potential uses in the food industry. Based on this review, the valorization of orange peels and pomaces can be carried out using green extraction methods with high quantities and qualities of extracts. Therefore, the extract can be used for health and wellness products.

Response Surface Methodology (RSM) was employed to optimize the extraction rate of phenolic and flavonoid contents from peanut skin by supercritical carbon dioxide (ScCO2) assisted by ethanol as entrainer. The studied extraction parameters were pressure (10 to 30 MPa), temperature (40 to 70 oC), and the ratio of ethanol (2.5 to 7.5%). Brunner’s and Esquivel’s models were applied to evaluate the extraction rate. The best-operating conditions, in the tested range, were 30 MPa, 40 °C, and 4.64% of ethanol ratio, with a maximum extraction rate of 0.22 mg/g.sec and 0.19 mg/g.sec of the phenolic and flavonoid content, respectively. The findings concluded that higher-pressure condition has a significant impact on the extraction rate of phenolic and flavonoid

Anthocyanins are one of the bioactive compounds in roselle that has many medicinal proposes. Anthocyanins are placed in the inner part of the roselle; therefore, combinations of two methods were applied to extract the anthocyanins. The first stage is employing supercritical carbon dioxide (ScCO2) to break the particle surface or outer layer of the roselle based on the total phenolic compounds (TPC) recovery, and the second step was to apply subcritical water extraction (SWE) for the extraction of anthocyanins. The objective is to determine the best conditions to obtain high yields of total anthocyanins compounds (TAC) from the roselle (Hibiscus sabdariffa) by employing a combination of ScCO2 and SWE. The optimal conditions of ScCO2 (first stage) were 19.13 MPa, 60 °C, and 4.31 mL/min, yielding 18.20%, and 80.34 mg/100 g TPC, respectively. The optimum conditions of SWE (second stage) were 9.48 MPa, 137 °C, and 6.14 mL/min, yielding 86.11% and 1224.61 mg/100 g TAC, respectively. The application of integrated ScCO2 and SWE proved successful in achieving high anthocyanins production and yield as compared to previous extraction methods. This approach may be used to extract the roselle with a greater anthocyanin’s concentration than the prior method.