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  • Open Access

    ARTICLE

    Anionic Polymerization of ε-Caprolactone Using Potassium tert-Butoxide/18-Crown-6 Initiating System

    YAN WANGA, LI-FANG ZHANGA,B,C,*, XIAO-QI WANGB

    Journal of Polymer Materials, Vol.37, No.1-2, pp. 77-89, 2020, DOI:10.32381/JPM.2020.37.1-2.6

    Abstract The effect of 18-crown-6 ether (18C6) on the anionic polymerization of ε-caprolactone (ε -CL) using potassium tert-butoxide (t-BuOK) as the initiator was studied. The experimental results showed that 18C6 in combination with t-BuOK exhibited high selectivity for ring opening relative to trans-esterification and improved control toward the ROP of ε-CL, producing poly(ε- caprolactone) (PCL) with much higher molecular weight and relatively narrow distribution compared to those using t-BuOK alone as the initiator.The influences of reaction conditions, such as monomer concentration, monomer/initiator molar ratio, and [18C6]/[t-BuOK] molar ratio, as well as reaction temperature and time on the polymerization have been examined… More >

  • Open Access

    ARTICLE

    The Conversion of Non-Dispersed Polymers into Low-Potassium Anti-Collapse Drilling Fluids

    Hao Hu1,2,3, Jian Guan4, Shanfa Tang1,2,3,*, Jialuo Rong1,2,3, Yuanpeng Cheng1,2,3

    FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.2, pp. 325-335, 2024, DOI:10.32604/fdmp.2023.042055

    Abstract Different drilling fluid systems are designed according to mineral composition, lithology and wellbore stability of different strata. In the present study, the conversion of a non-dispersed polymer drilling fluid into a low potassium anti-collapsing drilling fluid is investigated. Since the two drilling fluids belong to completely different types, the key to this conversion is represented by new inhibitors, dispersants and water-loss agents by which a non-dispersed drilling fluid can be turned into a dispersed drilling fluid while ensuring wellbore stability and reasonable rheology (carrying sand—inhibiting cuttings dispersion). In particular, the (QYZ-1) inhibitors and (FSJSS-2) dispersants are used. The former can… More >

  • Open Access

    ARTICLE

    Optimization of Anti-Collapse Drilling Fluid Systems with High Potassium Content

    Yu Xia1, Jian Guan4, Yong Gao5, Shanfa Tang1,2,3,*, Jialuo Rong1

    FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1609-1622, 2023, DOI:10.32604/fdmp.2023.025263

    Abstract The ash mudstone in some oil formations is highly water-sensitive. The oil formation is fractured, and the risk of well leakage and collapse is not negligible. This study presents a countermeasure for well collapse prevention, based on a “force-chemistry synergistic balance” approach and the utilization of environmentally friendly and efficient hydration inhibitors. The relevance of this approach is demonstrated considering a drilling fluid system with the high potassium content. The analysis shows that the system can maintain good rheological properties, filtration loss and suspension stability even after aging at 130°C for 16 h. The primary roll recovery of rock chips… More >

  • Open Access

    ARTICLE

    Improvement of Selected Morphological, Physiological, and Biochemical Parameters of Banana (Musa acuminata L.) Using Potassium Silicate under Drought Stress Condition Grown in vitro

    Hosny Abdel Aziz1, Mohamed Sharaf2,3, Magdy Omar4, Ahmed Abou El-Yazied5, Nada Ibrahim AlJwaizea6, Shaimaa Ismail5, Mohamed M. A. Omar7, Khadiga Alharbi6,*, Amr Elkelish8,9, Moataz Tawfik10

    Phyton-International Journal of Experimental Botany, Vol.92, No.4, pp. 1019-1036, 2023, DOI:10.32604/phyton.2023.026769

    Abstract Drought stress has become more common in recent years as a result of climate change impacts on the production of banana crops and other fruit trees. The growth and productivity of Musa spp are severely impacted by the gradual degradation of water resources and the erratic distribution pattern of annual precipitation amount. The aim of the work includes increased drought tolerance in light of water scarcity in the world as a result of the bananas’ being gluttonous for water needs. This investigation was carried out from 2019 to 2020 to study the effect of potassium silicate on morphological growth and… More >

  • Open Access

    ARTICLE

    Green Synthesis for Lignin Plasticization: Aqueous Graft Copolymerization with Methyl Methacrylate

    Sinto Jacob1, Manjusri Misra1,2, Amar Mohanty1,2,*

    Journal of Renewable Materials, Vol.1, No.2, pp. 154-165, 2013, DOI:10.7569/JRM.2012.634107

    Abstract This study investigated the use of potassium persulfate (KPS) as an initiator for the grafting of methyl methacrylate (MMA) onto softwood kraft lignin. Ammonium iron (II) sulfate hexahydrate was used as a catalyst to overcome the inherent inhibition of lignin to free radical grafting and to make lignin copolymer under mild conditions using an aqueous medium. The infl uence of temperature, initiator concentration, time of reaction and monomer concentration on percentage of grafting were studied. A maximum of 31% grafting was achieved at 55ο C. Graft copolymer was identifi ed from the Fourier transform infrared (FTIR) spectrum by the new… More >

  • Open Access

    ARTICLE

    Application of two forms of silicon and their impact on the postharvest and the content of bioactive compounds in cucumber (Cucumis sativus L.) fruits

    YOLANDA GONZÁLEZ-GARCÍA1, VALERIA FLORES-ROBLES2, GREGORIO CADENAS-PLIEGO3, ADALBERTO BENAVIDES-MENDOZA4, MARCELINO CABRERA DE LA FUENTE4, ALBERTO SANDOVAL-RANGEL4, ANTONIO JUÁREZ-MALDONADO1,*

    BIOCELL, Vol.46, No.11, pp. 2497-2506, 2022, DOI:10.32604/biocell.2022.021861

    Abstract The metabolic activity of the fruits continues even after harvest, which results in the loss of bioactive compounds, a decrease in the quality of the fruits, softening and browning, among other negative effects. The use of certain elements such as silicon can improve postharvest quality, since it is involved in the metabolic, physiological and structural activity of plants, moreover can increase the quality of the fruits. In addition, nanotechnology has had a positive impact on crop yield, nutritional value, fruit quality and can improve antioxidant activity. For these reasons, the use of beneficial elements such as silicon in the form… More >

  • Open Access

    ARTICLE

    Evaluation of the hepatoprotective and antioxidant effects of Tegillarca granosa flesh body extract against potassium bromide toxicity via targeting the histomorphometry, chromosomal and expressions of TGF-β1, VEGF and COX-2 genes in rats

    ALI H. ABU ALMAATY1, BASMA M. HENDAM2, FAYEZ ALTHOBAITI3, EMAN FAYAD3,*, YASMIN M. ABD EL-AZIZ1

    BIOCELL, Vol.46, No.1, pp. 219-234, 2022, DOI:10.32604/biocell.2022.017623

    Abstract The hepatotoxic effect of potassium bromide (KBr) on rat liver tissues were determined, as well as the potential protective effect of Tegillaraca granosa (T. granosa) flesh body extract. Twenty adult male albino rats were equally distributed into four groups; Group (I) treated with physiological saline (control group), Group (II) was orally gavaged by 200 mg/kg of T. granosa body extract day after day, Group (III) was intoxicated by KBr (150 mg/kg bwt day after day orally) and finally, Group (IV) was given a combination of T. granosa flesh body extract plus KBr with similar doses in the second and third… More >

  • Open Access

    ARTICLE

    Preparation and Characterization of Potassium Monopersulfate/Ethyl Cellulose Microcapsules and Their Sustained Release Performance

    Qiaoguang Li1, Xuming Yan1, Jialong Chen1, Xugang Shu1,*, Puyou Jia2,*, Xiangjun Liang3

    Journal of Renewable Materials, Vol.9, No.10, pp. 1673-1684, 2021, DOI:10.32604/jrm.2021.014695

    Abstract Environmental cleaning is an important aspect of bacteria control. Ethyl cellulose microcapsules containing potassium monopersulfate (PMCM) were prepared by emulsified solvent diffusion method. The chemical structure and microstructure of the obtained PMCM was characterized by methods of Fourier transform infrared spectroscopy (FT-IR), optical microscopy, scanning electron microscopy and X-ACT energy dispersive X-ray spectroscopy. The SEM micrographs of the PMCM containing 21.6% of C, 46.8% of O, 10.7% of S and 19.4% of K was relatively smooth. Thermal stability, sustained release performance, and antimicrobial activity of PMCM were investigated. The results showed that the drug loading and encapsulation efficiency of PMCM… More >

  • Open Access

    ARTICLE

    Synthesis and Characterization of Green Potassium Nanoparticles from Sideroxylon Capiri and Evaluation of Their Potential Antimicrobial

    Judith Constantino-Alcazar1, Miguel Abud-Archila1, Benjamín Valdez-Salas3, Federico Gutierrez-Miceli1, Carlos Ceceña-Duran2, Blanca López-Valenzuela2, Daniel Gonzalez-Mendoza2,*,*

    Journal of Renewable Materials, Vol.9, No.10, pp. 1699-1706, 2021, DOI:10.32604/jrm.2021.015645

    Abstract In the present study, the green synthesis of potassium nanoparticles (K-NPs) was assessed using aqueous extract of Sideroxylon capiri. The potassium nanoparticles were analyzed by UV-visible spectroscopic techniques, X-ray spectrometers of energy dispersive (SEM-EDS) and dynamic light scattering. The results showed high values at 3.5 keV confirming the formation of potassium nanoparticles and the SEM analysis showed an agglomerated particles size between 360 to 200 nm with a spherical morphology. The K-NPs showed an effective antibacterial activity against the test organisms mainly with Bacillus cereus, Enterobacter aerogenes, Fusarium solani and Botrytis cinerea. However further studies about nanotoxicity of K-NPs are… More >

  • Open Access

    ARTICLE

    Effects of Different Potassium (K) Fertilizer Rates on Yield Formation and Lodging of Rice

    Tantan Zhang1,2,#, Xiaoping He3,#, Binglin Chen1,#, Longxin He1,2, Xiangru Tang1,2,*

    Phyton-International Journal of Experimental Botany, Vol.90, No.3, pp. 815-826, 2021, DOI:10.32604/phyton.2021.014168

    Abstract As one of the most important nutrients for plants, potassium (K) has substantial effects on growth and development of crops. Present study was conducted in three different sites in South China in late season in 2019 with the objective to study the effects of different applied amounts of K fertilizer on yield formation and lodging of rice. Four K fertilizer treatments, K0: 0 kg potassium oxide (K2O) ha−1 (control); K1: 64.20 kg K2O ha−1 ; K2: 128.55 kg K2O ha−1 and K3 153.90 kg K2O ha−1 were applied in the field experiment. The results showed that K2 and K3 treatments… More >

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