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Journal articles on the topic 'Diphenyl urea'

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Author: Grafiati
Published: 9 March 2023

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1

Wu, Yi-Cong, Xin-Yue Ren, and Guo-Wu Rao. "Research Progress of Diphenyl Urea Derivatives as Anticancer Agents and Synthetic Methodologies." Mini-Reviews in Organic Chemistry 16, no. 7 (October 8, 2019): 617–30. http://dx.doi.org/10.2174/1570193x15666181029130418.

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The malignant neoplasm, which is recognized as cancer, is a serious threat to human health and frequently-occurring disease. Diphenylurea, an important link structure in the design of active substance for treating cancer due to its near-perfect binding with certain acceptors, has demonstrated many activities against several human cancer cell lines. Various novel compounds with diphenyl urea as anticancer agents were constructed with the successful development of sorafenib. Diphenylurea is utilized to treat cancer by inhibiting cell signaling transduction, such as RAS-RAFMEK- ERK signaling pathway and PI3K-Akt-mTOR pathway. In addition, this structure inhibits tumor cell growth by inhibiting receptor tyrosine kinases multiply, such as Vascular Endothelial Growth Factor Receptors (VEGFRs), Platelet-Derived Growth Factor Receptors (PDGFRs), Epidermal Growth Factor Receptors (EGFRs). It regulates the pH value in cells by inhibiting CAIX/XII and to achieve cancer therapeutic effect. Besides, the diphenyl urea structure is applied to the synthesis of reagents like Aurora kinases inhibitors and HDAC inhibitors that affect cell division and differentiation to treat cancer. To reach the goal of treating tumor, this structure is also used as a DNA-directed alkylating agent by affecting the expression of genes. An application of the most representative diphenyl urea derivatives as antitumor agents is summarized in this review, focusing on their mechanisms bound to the targets. Meanwhile, the progress of researches on methods of synthesizing diphenyl urea derivatives is provided.
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2

Nguyễn, Thị Hồng Thắm, Đinh Châu Phan, Thị Hồng Thanh Nguyễn, Thị Xuân Thu Ngô, Thị Thủy Đặng, and Bình Dương Vũ. "SYNTHESIS OF MEMANTINE HYDROCHLORIDE BY DIRECT AMINOATION OF 1-BROMO-3,5-DIMETHYLADAMANTANE WITH." VietNam Military Medical Unisversity 47, no. 9 (December 1, 2022): 140–48. http://dx.doi.org/10.56535/jmpm.v47i9.214.

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Objectives: To optimize the synthesis process of memantine hydrochloride by direct aminoation of 1-bromo-3,5-dimethyladamantane with urea. Materials and methods: Using the basic chemical reactions to optimize the reaction conditions. Results: The optimal conditions of the memantine hydrochloride synthesis process include: The reaction solution was diphenyl ether; the reaction temperature was 170oC within 4 hours (in the first step) and 100oC within 2 hours (in the second step); the molar ration of 1-bromo-3,5-dimethyladmantane: urea: diphenyl ether was 1:3:2.5; the duration of the reaction was 6 hours and the overall yields were 75.81%. Conclusion: The synthesis process of memantine hydrochloride by direct aminoation with urea was established. The finished products were determined by IR, MS, and NMR spectra and met the standards of USP 43.
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3

Ferro, D., and G. Della Gatta. "Enthalpies of sublimation and fusion of monophenylurea and diphenyl-1,3 urea." Thermochimica Acta 122, no. 1 (December 1987): 189–95. http://dx.doi.org/10.1016/0040-6031(87)80119-3.

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4

Sallenave, X., S. Delbaere, S. Ahmed, G. Vermeersch, and J. L. Pozzo. "5-Ureido-3,3-diphenyl-3H-naphtho[2,1-b]pyrans: Photoswitchable self-assembling architectures." International Journal of Photoenergy 6, no. 4 (2004): 169–73. http://dx.doi.org/10.1155/s1110662x04000212.

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5-Ureido-3,3-diphenyl-3H-naphtho[2,1-b]pyrans have been synthesized and their photochromic properties have been quantified using UV-Visible spectroscopy. The urea pattern is responsive for the selfassembling properties under both colourless and coloured forms whereas the corresponding amino derivatives do not show any aggregative properties. The geometries of the different states have been assigned using1Hand19FNMR spectroscopies, and thereafter their respective kind of aggregates could be proposed through the different inter- and intramolecular interactions. Upon UV irradiation, the pyranic ring is opened and the resulting photogenerated carbonyl group is competing with the urea in the self-assembling process and consequently strongly affects the supramolecular assemblies. The inter- and intramolecular contributions have been quantified through 1D and 2D NMR experiments along with the variation in the concentration.
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5

Obiol-Pardo, Cristian, Gema Alcarraz-Vizán, Marta Cascante, and Jaime Rubio-Martinez. "Diphenyl Urea Derivatives as Inhibitors of Transketolase: A Structure-Based Virtual Screening." PLoS ONE 7, no. 3 (March 5, 2012): e32276. http://dx.doi.org/10.1371/journal.pone.0032276.

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6

Usha, Veeraraghavan, Sudagar S. Gurcha, Andrew L. Lovering, Adrian J. Lloyd, Athina Papaemmanouil, Robert C. Reynolds, and Gurdyal S. Besra. "Identification of novel diphenyl urea inhibitors of Mt-GuaB2 active against Mycobacterium tuberculosis." Microbiology 157, no. 1 (January 1, 2011): 290–99. http://dx.doi.org/10.1099/mic.0.042549-0.

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In contrast with most bacteria, which harbour a single inosine monophosphate dehydrogenase (IMPDH) gene, the genomic sequence of Mycobacterium tuberculosis H37Rv predicts three genes encoding IMPDH: guaB1, guaB2 and guaB3. These three genes were cloned and expressed in Escherichia coli to evaluate functional IMPDH activity. Purified recombinant Mt-GuaB2, which uses inosine monophosphate as a substrate, was identified as the only active GuaB orthologue in M. tuberculosis and showed optimal activity at pH 8.5 and 37 °C. Mt-GuaB2 was inhibited significantly in vitro by a panel of diphenyl urea-based derivatives, which were also potent anti-mycobacterial agents against M. tuberculosis and Mycobacterium smegmatis, with MICs in the range of 0.2–0.5 μg ml−1. When Mt-GuaB2 was overexpressed on a plasmid in trans in M. smegmatis, a diphenyl urea analogue showed a 16-fold increase in MIC. Interestingly, when Mt-GuaB orthologues (Mt-GuaB1 and 3) were also overexpressed on a plasmid in trans in M. smegmatis, they also conferred resistance, suggesting that although these Mt-GuaB orthologues were inactive in vitro, they presumably titrate the effect of the inhibitory properties of the active compounds in vivo.
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7

Vaishnav, Yogesh, Aloksingh Thakur, Chanchal Deep Kaur, Shekhar Verma, Achal Mishra, Sanmati Kumar Jain, and Piyush Ghode. "QSAR Analysis of some N, N-diphenyl urea derivatives as CCR5 Receptor Antagonist." Research Journal of Pharmacy and Technology 11, no. 9 (2018): 3802. http://dx.doi.org/10.5958/0974-360x.2018.00697.2.

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8

Du, Pengfei, Meiyin Wu, Xuanxuan Liu, Zhen Zheng, Xinling Wang, Thomas Joncheray, and Yuefan Zhang. "Diels-Alder-based crosslinked self-healing polyurethane/urea from polymeric methylene diphenyl diisocyanate." Journal of Applied Polymer Science 131, no. 9 (December 11, 2013): n/a. http://dx.doi.org/10.1002/app.40234.

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9

Guin, Akshya Kumar, Suryakanta Nayak, Manish Kumar Bhadu, Veena Singh, and Tapan Kumar Rout. "Development and Performance Evaluation of Corrosion Resistance Self-Healing Coating." ISRN Corrosion 2014 (April 23, 2014): 1–7. http://dx.doi.org/10.1155/2014/979323.

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Polymer based nanocapsule was developed using core-cell approach, where the core material was methyl diphenyl diisocyanate and the cell material was urea-formaldehyde. The synthesized capsules of 100 to 800 nm size were incorporated into sol-gel matrix to prepare a final coating for steel protection. This coating was found protecting the steel at the damage or crack locations in 3.5% NaCl solution. SEM micrographs confirmed healing of the coating at the damage or crack points.
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10

Hauback, Bj�rn C., Tor J. Brobak, Frode Mo, Astrid M. Schie Bergan, and Eva H. M�rkved. "Structure ofN, N?-diphenyl-N-(2-pyridmyl)urea hemihydrate: A crystallographic and spectroscopic investigation." Journal of Crystallographic and Spectroscopic Research 18, no. 6 (December 1988): 729–45. http://dx.doi.org/10.1007/bf01164294.

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11

Shaneh, Shideh, Fatemeh Shokrolahi, Parvin Shokrollahi, Hamid Yeganeh, and Hossein Omidian. "Structural engineering to control density, conformation, and bioactivity of the poly(ethylene glycol)-grafted poly(urethane urea) scaffolds." Journal of Bioactive and Compatible Polymers 34, no. 2 (December 19, 2018): 209–23. http://dx.doi.org/10.1177/0883911518819224.

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Poly(urethane urea) scaffolds were fabricated through combined salt leaching and solvent casting methods. The scaffolds were then functionalized via aminolysis with poly(ethylene glycol) (PEG- g-PUU). To compare its bioactivity, gelatin was also grafted onto the aminolyzed poly(urethane urea) surface (Gel- g-PUU). Chemical changes at the surface were then monitored using quantitative/qualitative methods. Grafting with both gelatin and poly(ethylene glycol) remarkably enhanced the wettability of poly(urethane urea). Proliferation of human adipose–derived mesenchymal stem cells on poly(urethane urea) and the modified poly(urethane urea)s was evaluated by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay. The cell experiment results showed that both the modified poly(urethane urea)s enhanced the attachment and proliferation of human adipose–derived mesenchymal stem cells compared to pure poly(urethane urea). Based on previous reports, while a supportive role is observed at adequate poly(ethylene glycol) graft densities, cell adhesion and proliferation are inhibited at very high grafting densities. To correlate the cell data to poly(ethylene glycol) conformations, the surface tension was measured. Data on human adipose–derived mesenchymal stem cells’ attachment/proliferation and contact angle/surface free energy together showed that the grafting density of poly(ethylene glycol) was regulated by optimizing aminolysis conditions, careful selection of poly(ethylene glycol)’s molecular weight, and bulk properties of the matrix poly(urethane urea). As a result, surface overcrowding and brush conformation of the poly(ethylene glycol) chains were avoided, and human adipose–derived mesenchymal stem cell attachment and proliferation occurred on the PEG- g-PUU scaffold at a comparable level to the Gel- g-PUU.
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12

Andraos, John. "A green metrics assessment of phosgene and phosgene-free syntheses of industrially important commodity chemicals." Pure and Applied Chemistry 84, no. 3 (November 19, 2011): 827–60. http://dx.doi.org/10.1351/pac-con-11-06-12.

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Synthesis plans for the following important industrial commodity chemicals using phosgene and phosgene-free chemistries have been analyzed and compared by green metrics to determine the most material-efficient routes so far developed (number of plans given in parentheses): dimethyl carbonate (DMC) (31), diphenyl carbonate (DPC) (40), diphenylurea (DPU) (23), methyl carbamate (MC) (8), methyl chloroformate (MCF) (6), methyl N-phenylcarbamate (MNPC) (25), methyl phenyl carbonate (MPC) (32), phenyl isocyanate (PI) (19), phenyl chloroformate (PCF) (10), and urea (13). Implications of these results are discussed.
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13

Asafu-Adjaye, Osei, Brian Via, and Sujit Banerjee. "Increasing Cold Tack of Polymeric Methylene Diphenyl Diisocyanate Resin with Partial Soy Flour Substitution." Forest Products Journal 70, no. 1 (January 1, 2020): 143–44. http://dx.doi.org/10.13073/fpj-d-19-00049.

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Abstract Partial substitution of polymeric methylene diphenyl diisocyanate resin with soy flour increases the cold tack of the resin to the level achieved by urea formaldehyde resin. The tack can be fine-tuned by adjusting the amount of soy flour added. The increase in tack is caused by the reaction of the isocyanate resin with the water contained in soy flour, as well as with hydroxyl and other groups present in soy flour components. The higher cold tack should increase the stability of pre-press mats, especially in particleboard manufacturing.
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14

Qian, Yuqing, Xiaowei An, Xiaofei Huang, Xiangqiang Pan, Jian Zhu, and Xiulin Zhu. "Recyclable Self-Healing Polyurethane Cross-Linked by Alkyl Diselenide with Enhanced Mechanical Properties." Polymers 11, no. 5 (May 1, 2019): 773. http://dx.doi.org/10.3390/polym11050773.

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Dynamic structures containing polymers can behave as thermosets at room temperature while maintaining good mechanical properties, showing good reprocessability, repairability, and recyclability. In this work, alkyl diselenide is effectively used as a dynamic cross-linker for the design of self-healing poly(urea–urethane) elastomers, which show quantitative healing efficiency at room temperature, without the need for any catalysts or external interventions. Due to the combined action of the urea bond and amide bond, the material has better mechanical properties. We also compared the self-healing effect of alkyl diselenide-based polyurethanes and alkyl disulfide-based polyurethanes. The alkyl diselenide has been incorporated into polyurethane networks using a para-substituted amine diphenyl alkyl diselenide. The resulting materials not only exhibit faster self-healing properties than the corresponding disulfide-based materials, but also show the ability to be processed at temperatures as low as 60 °C.
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15

Hemalatha, K., and D. Ilangeswaran. "Synthesis and Characterization of Piperidin-4-one Derivatives Using Green Solvent." Asian Journal of Chemistry 32, no. 4 (February 25, 2020): 981–84. http://dx.doi.org/10.14233/ajchem.2020.22589.

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A deep eutectic solvent of glucose-urea was found to be an inexpensive and effective reaction medium in the synthesis of piperidin-4-one derivatives. In this work, 3-methyl-2,6-diphenyl piperidin-4-one (4a), 3,5-dimethyl-2,6-diphenylpiperidin-4-one (4b), 2,6-diphenylpiperidin-4-one (4c), piperidin-4- one (4d), 3,5-dimethylpiperidin-4-one (4e), 3-methyl-2,6-di(2-hydroxyphenyl)piperidin-4-one (4f), 3,5-dimethyl 2,6-di(2-hydroxyphenyl)piperidin-4one (4g) were synthesized using a deep eutectic solvent (DES) of glucose and urea with the percentage composition of 60:40. The yields of these products were 82, 78, 75, 68, 72, 70 and 70 %, respectively. The products obtained were characterized by FT-IR and 1H NMR spectroscopic techniques. A synthesis of piperidin-4-one derivatives by using this green solvent was considered to be new environmentally safe synthetic method.
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16

Verkman, A. S., and H. E. Ives. "Water permeability and fluidity of renal basolateral membranes." American Journal of Physiology-Renal Physiology 250, no. 4 (April 1, 1986): F633—F643. http://dx.doi.org/10.1152/ajprenal.1986.250.4.f633.

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Water and nonelectrolyte permeability in basolateral membrane vesicles (BLMV) isolated from rat and rabbit renal cortex were characterized. Osmotic water (Pf) and solute (Ps) permeabilities were determined from the time course of scattered light intensity in response to osmotic gradients. In rabbit BLMV, Pf = 2.5 X 10(-2) cm/s, Purea = 1.2 X 10(-6) cm/s, and sigma urea = 0.95 (23 degrees C). Relative solute permeabilities were urea, 1; thiourea, 0.83; ethylene glycol, 9.7; glycerol, 4.6; formamide, 20; and acetamide, 12. Pf and Purea were not altered by organic mercurials, phloretin, urea, and high-affinity urea analogues. delta H (12-50 degrees C) was 10.7 and 2.5 kcal/mol for Purea and Pf, respectively; in contrast, reported delta H for Pf in rabbit brush-border membrane vesicles (BBMV) was 2 kcal/mol (T less than 33 degrees C) and 14 kcal/mol (T greater than 33 degrees C). To examine whether membrane fluidity changes were associated with this difference, fluorescence anisotropy decay was measured using 1,6-diphenyl-1,3,5-hexatriene (DPH). In both BLMV and BBMV, DPH rotation was hindered at all temperatures (5-53 degrees C). Changes in steady-state anisotropy were attributable to changes in DPH rotational freedom rather than to changes in DPH rotational rate without evidence for a definitive membrane thermotropic phase transition. These results suggest that BLMV urea transport occurs by lipid diffusion and that osmotic water transport is rapid and may be facilitated. A comparison of transepithelial Pf with BLMV and BBMV Pf is consistent with transcellular osmotic water flow in the proximal tubule.
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17

Barikani, Majid, Naghmeh Fazeli, and Mehdi Barikani. "Study on thermal properties of polyurethane-urea elastomers prepared with different dianiline chain extenders." Journal of Polymer Engineering 33, no. 1 (February 1, 2013): 87–94. http://dx.doi.org/10.1515/polyeng-2012-0137.

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Abstract A number of polyurethane prepolymers based on polycaprolactone diol (PCL) and 4,4′-diphenyl methane diisocyanate (MDI) were synthesized and extended with different dianilines such as: 4,4′-methylenebis(2,6-diisopropylaniline) (M-DIPA), 4,4′-methylenebis(2,6diethylaniline) (M-DEA), 4,4′-methylenebis(ortho chloroaniline) (MOCA), 4,4′-methylenebis(2-isopropyl-6-methylaniline) (M-MIPA) and 4,4′-methylenebis(3-chloro-2,6-diethylaniline) (M-CDEA). Infrared (IR) spectroscopy was used to check the end of the polymerization reaction in addition to the polymer characterization. The effect of the dianiline structure on the thermal properties of the cast films were studied through dynamic mechanical measurements (DMTA), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis. It was found that the thermal properties and thermal stability of polyurethane are strongly affected by the molecular structure of the dianiline chain extender.
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18

Damodharan, Jaishree, Kanchana Gopinath, and Kesavasamy Ramasamy. "Investigation on Structural, Optical and Thermal Properties of Diphenyl Urea—An Organic Non-Linear Optical Crystal." Journal of Minerals and Materials Characterization and Engineering 03, no. 02 (2015): 49–54. http://dx.doi.org/10.4236/jmmce.2015.32007.

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19

Mulla, Shafeek A. R., Chandrashekhar V. Rode, Ashutosh A. Kelkar, and Sunil P. Gupte. "Activity of homogeneous transition metal catalysts for oxidative carbonylation of aniline to N,N′diphenyl urea." Journal of Molecular Catalysis A: Chemical 122, no. 2-3 (August 1997): 103–9. http://dx.doi.org/10.1016/s1381-1169(97)00023-x.

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20

Gao, Jun Jie, Hui Quan Li, and Yi Zhang. "Synthesis of methyl N-phenyl carbamate from dimethyl carbonate and 1,3-diphenyl urea under mild conditions." Chinese Chemical Letters 18, no. 2 (February 2007): 149–51. http://dx.doi.org/10.1016/j.cclet.2006.12.014.

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21

Born, L., and H. Hespe. "On the Physical Crosslinking of Amine-Extended Polyurethane Urea Elastomers: A Crystallographic Analysis of Bis-Urea from Diphenyl Methane-4-Isocyanate and 1,4-Butane Diamine." Berichte der Bunsengesellschaft für physikalische Chemie 89, no. 11 (November 1985): 1197. http://dx.doi.org/10.1002/bbpc.19850891116.

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22

Born, L., and H. Hespe. "On the physical crosslinking of amine-extended polyurethane urea elastomers: A crystallographic analysis of bis-urea from diphenyl methane-4-isocyanate and 1,4-butane diamine." Colloid & Polymer Science 263, no. 4 (April 1985): 335–41. http://dx.doi.org/10.1007/bf01412250.

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23

Michea, L., D. R. Ferguson, E. M. Peters, P. M. Andrews, M. R. Kirby, and M. B. Burg. "Cell cycle delay and apoptosis are induced by high salt and urea in renal medullary cells." American Journal of Physiology-Renal Physiology 278, no. 2 (February 1, 2000): F209—F218. http://dx.doi.org/10.1152/ajprenal.2000.278.2.f209.

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We investigated the effects of hyperosmolality on survival and proliferation of subconfluent cultures of mIMCD3 mouse renal collecting duct cells. High NaCl and/or urea (but not glycerol) reduces the number of viable cells, as measured with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT). Raising osmolality from a normal level (300 mosmol/kg) to 550–1,000 mosmol/kg by adding NaCl and/or urea greatly increases the proportion of cells in the G2M phase of the cell cycle within 8 h, as measured by flow cytometry. Up to 600 mosmol/kg the effect is only transient, and by 12 h at 550 mosmol/kg the effect reverses and most cells are in G1. Flow cytometry with 5-bromodeoxyuridine (BrdU) pulse-chase demonstrates that movement through the S phase of the cell cycle slows, depending on the concentrations of NaCl and/or urea, and that the duration of G2M increases greatly (from 2.5 h at 300 mosmol/kg to more than 16 h at the higher osmolalities). Addition of NaCl and/or urea to total osmolality of 550 mosmol/kg or more also induces apoptosis, as demonstrated by characteristic electron microscopic morphological changes, appearance of a subdiploid peak in flow cytometry, and caspase-3 activation. The number of cells with subdiploid DNA and activated caspase-3 peaks at 8–12 h. Caspase-3 activation occurs in all phases of the cell cycle, but to a disproportionate degree in G0/G1 and S phases. We conclude that elevated NaCl and/or urea reduces the number of proliferating mIMCD3 cells by slowing the transit through the S phase, by cell cycle delay in the G2M and G1, and by inducing apoptotic cell death.
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24

Tahir, Muhammad, Gert Heinrich, Nasir Mahmood, Regine Boldt, Sven Wießner, and Klaus Stöckelhuber. "Blending In Situ Polyurethane-Urea with Different Kinds of Rubber: Performance and Compatibility Aspects." Materials 11, no. 11 (November 2, 2018): 2175. http://dx.doi.org/10.3390/ma11112175.

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Specific physical and reactive compatibilization strategies are applied to enhance the interfacial adhesion and mechanical properties of heterogeneous polymer blends. Another pertinent challenge is the need of energy-intensive blending methods to blend high-tech polymers such as the blending of a pre-made hard polyurethane (-urea) with rubbers. We developed and investigated a reactive blending method to prepare the outstanding blends based on polyurethane-urea and rubbers at a low blending temperature and without any interfacial compatibilizing agent. In this study, the polyurethane-urea (PUU) was synthesized via the methylene diphenyl diisocyanate end-capped prepolymer and m-phenylene diamine based precursor route during blending at 100 °C with polar (carboxylated nitrile rubber (XNBR) and chloroprene rubber (CR)) and non-polar (natural rubber (NR), styrene butadiene rubber (sSBR), and ethylene propylene butadiene rubber (EPDM)) rubbers. We found that the in situ PUU reinforces the tensile response at low strain region and the dynamic-mechanical response up to 150 °C in the case of all used rubbers. Scanning electron microscopy reveals a stronger rubber/PUU interface, which promotes an effective stress transfer between the blend phases. Furthermore, energy filtered transmission electron microscopy (EFTEM) based elemental carbon map identifies an interphase region along the interface between the nitrile rubber and in situ PUU phases of this exemplary blend type.
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25

Inoue, Yutaka, Daichi Niiyama, Isamu Murata, and Ikuo Kanamoto. "Usefulness of Urea as a Means of Improving the Solubility of Poorly Water-Soluble Ascorbyl Palmitate." International Journal of Medicinal Chemistry 2017 (November 6, 2017): 1–9. http://dx.doi.org/10.1155/2017/4391078.

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The aim of this study was to evaluate complexes of L-ascorbyl palmitate (ASCP) and urea (UR). This evaluation involved differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), near-infrared spectroscopy (NIR), a solubility test, a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging test, and a mushroom tyrosinase inhibition assay. Physicochemical evaluation revealed that ASCP/UR complexes form at a molar ratio of 1/12. The solubility test revealed that ASCP/UR complexes had increased solubility compared to ASCP. The DPPH radical scavenging test and mushroom tyrosinase inhibition assay revealed that the activity of ASCP/UR complexes was not impaired by complex formation. These results are probably due to the tetragonal crystal system of UR changing to a hexagonal crystal system and interaction with the alkyl group of ASCP.
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26

Luo, Peng, Chuanmin Yang, Mengyao Li, and Yueqi Wang. "Manufacture of thin rice straw particleboards bonded with various polymeric methane diphenyl diisocyanate/ urea formaldehyde resin mixtures." BioResources 15, no. 1 (December 17, 2019): 935–44. http://dx.doi.org/10.15376/biores.15.1.935-944.

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Reducing particleboard thickness is one of the major approaches to decrease consumption volume of particleboard for furniture manufacture. This study employed an adhesive mixture of polymeric methane diphenyl diisocyanate (PMDI) and urea formaldehyde (UF) to produce single-layer medium density thin rice straw particleboard. The effects of various PMDI/UF formulations as well as board density on mechanical properties and water resistance of rice straw particleboard were studied. The results indicated that the mechanical properties and water resistance of the thin rice straw particleboard were appreciably affected by resin formulation. The panels bonded with PMDI/UF adhesive mixtures had mechanical properties and water resistance far superior to those bonded with UF. Higher PMDI content levels in resin mixtures led to improved mechanical properties and water resistance. Density influenced mechanical properties and water resistance of the thin rice straw particleboard. Increasing the density of the panel could upgrade the mechanical properties of the thin rice straw particleboard. The experimental outcomes showed that PMDI/UF resin systems had potential to substitute for pure PMDI resin in producing thin rice straw particleboard, which could effectively lower manufacturing cost and bring economic efficiencies due to reduced amount of pricey PMDI.
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27

Ahmad, Syed Sabhi, Inayatullah Tahir, Arif Shafi Wani, Riyaz Ahmad Dar, and Shaziya Nisar. "Adenine type and diphenyl urea derived cytokinins improve the postharvest performance of Iris germanica L. cut scapes." Physiology and Molecular Biology of Plants 24, no. 6 (June 3, 2018): 1127–37. http://dx.doi.org/10.1007/s12298-018-0554-z.

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28

Cherala, Swapna, Harikiran Lingabathula, Rama Ganta, Srinivas Ampati, and Sarangapani Manda. "Synthesis and Anti-Inflammatory Activity of a Novel Series of Diphenyl-1,2,4-triazoles and Related Derivatives." E-Journal of Chemistry 9, no. 4 (2012): 2510–15. http://dx.doi.org/10.1155/2012/278695.

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In the present investigation we have synthesized a series of new 1-[3-(4-substitutedphenyl)-5-phenyl-4H-1,2,4-triazol-4-yl]urea and 1-[3-(4-substitutedphenyl)-5-phenyl-4H-1,2,4-triazol-4-yl]thiourea derivatives (4Ia - 4IId). The newly synthesised derivatives were characterized by using the data of IR,1H NMR and Mass Spectral analysis. Thus synthesised and characterized targetted compounds were further screened for their anti-inflammatory activity by using Carrageenan – induced paw edema rat model. Among all the newly synthesized derivatives, Compounds 4Ia-4Ic and Compounds 4IIa-4IId were reduced the inflammation very significantly (p<0.0001), thus these compounds showed promising anti-inflammatory activity and only one compound (4Id) showed moderate anti-inflammatory activity (p<0.05).
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Rachtanapun, Pornchai, Teerarat Sattayarak, and Nisachon Ketsamak. "Correlation of density and properties of particleboard from coffee waste with urea–formaldehyde and polymeric methylene diphenyl diisocyanates." Journal of Composite Materials 46, no. 15 (February 8, 2012): 1839–50. http://dx.doi.org/10.1177/0021998311426624.

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Bag, Bidhan C., Makireddi Sai, Mahavir P. Kaushik, Krishnamurthy Sekhar, and Chiranjib Bahttacharya. "Pretreatment of wastewater containing a mixture of organic pollutants obtained from a CC2 plant by coagulation." Water Science and Technology 58, no. 5 (September 1, 2008): 1071–77. http://dx.doi.org/10.2166/wst.2008.452.

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Coagulation is one of the most important physicochemical treatment steps in industrial wastewater to reduce the suspended and colloidal materials responsible for colour and turbidity of the wastewater. The manufacturing plant of N,N′-Dichloro bis (2,4,6-trichlorophenyl) urea (CC2) produces wastewater containing pyridine, acetic acid and diphenyl urea (DPU). The wastewater also contains lot of suspended solids like CC2 and various poly-aromatic compounds. In our present investigation, our basic aim was to find an effective coagulation process for the pretreatment of wastewater discharged from the CC2 plant. Studies were conducted to find out a suitable and effective coagulant for pretreatment of this wastewater. Various coagulating agents such as alum, ferric chloride, sodium carboxymethyl cellulose (Na-CMC) were used. Alum was found to be the most effective coagulant. Coagulation of the wastewater resulted in the total suspended solids (TSS) removal in the range of 92–94% and chemical oxygen demand (COD) removal in the range of 59 to 65% at a dose of 500 mg L−1 of alum at a pH ≥ 7.0. After coagulation the concentration of pyridine in wastewater was found to be reduced by 10.0% and that of DPU 40–45% with a dosage of 500 mg L−1 alum.
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Wang, Luyu, Ye Zhu, Qun Xiang, Zhixuan Cheng, Yang Chen, and Jiaqiang Xu. "One novel humidity-resistance formaldehyde molecular probe based hydrophobic diphenyl sulfone urea dry-gel: Synthesis, sensing performance and mechanism." Sensors and Actuators B: Chemical 251 (November 2017): 590–600. http://dx.doi.org/10.1016/j.snb.2017.05.074.

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32

Chen, Li-Juan, Jie Bao, Fu-Ming Mei, and Guang-Xing Li. "Oxidative carbonylation of aniline to N,N′-diphenyl urea catalyzed by cobalt(II)–Schiff base complex/pyridine catalytic system." Catalysis Communications 9, no. 5 (March 2008): 658–63. http://dx.doi.org/10.1016/j.catcom.2007.07.016.

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Harish, N., N. Kathyayini, and N. Nagaraju. "Studies on the catalytic activity of mesoporous alumina-aluminophosphate (Al2O3–AlPO4) materials in the synthesis of N,N′-diphenyl urea." Reaction Kinetics, Mechanisms and Catalysis 125, no. 2 (September 3, 2018): 937–49. http://dx.doi.org/10.1007/s11144-018-1457-2.

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34

Ivanov, Iliyan. "Synthesis of 6,7-dimethoxy-3,4-diphenyl-2(1H)-quinazolinone from 1-(3,4-dimethoxyphenyl)-urea and benzoic acid in polyphosphoric acid." Molbank 2006, no. 5 (September 1, 2006): M492. http://dx.doi.org/10.3390/m492.

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35

Zhang, Yan Hua, Ji You Gu, Ying Feng Zuo, Ming Wei Di, Hai Yan Tan, and Li Bin Zhu. "Mechanical Properties of Wheat Straw Particleboard Using Composite Adhesives." Advanced Materials Research 113-116 (June 2010): 2096–99. http://dx.doi.org/10.4028/www.scientific.net/amr.113-116.2096.

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The purpose of the study was to use a cheap wheat straw to manufacture particleboard. Wheat straws offer great promise and new challenges as replacement for wood in processed wood products. The particleboard was produced using composite adhesive which the urea-formaldehyde (UF) adhesives modified by emulsifiable polymeric methylene diphenyl diisocyanate (EPU). The properties of the particleboard was evaluated by measuring internal bonding strength(IB), thickness swelling, modulus of rupture(MOR), modulus of elasticity (MOE) and formaldehyde emission. The optimal condition was chosen at density of 0.75g/cm3, UF/EPU ratio of 70/30, adhesive amounts of 10% based on the dry amounts of wheat straw. The test results showed that maximum dry internal bonding strength, wetting internal bonding strength, modulus of rupture, modulus of elasticity was 0.45MPa, 0.072MPa, 31.50MPa and 4564MPa, respectively. The thickness swelling (TS2h) and thickness swelling (TS24h) was 3.51% and 11.1%, respectively. The free formaldehyde of wheat straw particleboard reached E0-type national standards.
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Tschannen, Christof, Ali Shalbafan, and Heiko Thoemen. "Development of an Electrically Conductive MDF Panel—Evaluation of Carbon Content and Resin Type." Polymers 15, no. 4 (February 11, 2023): 912. http://dx.doi.org/10.3390/polym15040912.

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Electronics in furniture and construction materials, in particular technologies which allow for a flexible and cable-free connection of electronics in such materials, are gaining broader interest. This study shows a further development of a concept to obtain highly conductive medium-density fibreboard panels (MDF) for furniture application. MDF were produced using two mixing processes (wet and dry) for wood and carbon fibres to investigate the effects of resin type (urea formaldehyde (UF) and polymeric methylene diphenyl diisocyanate (pMDI)) and carbon fibre content on their mechanical, physical, and electrical properties. Overall, wet mixed fibres showed better electrical but reduced mechanical properties. Modulus of elasticity (MOE) and bending strength (MOR) values of 3500 MPa and 35 MPa, respectively, and internal bond (IB) values of 0.45 to 0.65 MPa with electrical conductivities of up to 230 S/m were achieved. The technology has been successfully implemented in a demonstration object showing the application in a small piece of furniture.
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Balaban, Milica, Vesna Antic, Marija Pergal, Iolanda Francolini, Andrea Martinelli, and Jasna Djonlagic. "The effect of the polar solvents on the synthesis of poly(urethane-urea-siloxane)s." Journal of the Serbian Chemical Society 77, no. 10 (2012): 1457–81. http://dx.doi.org/10.2298/jsc111025056b.

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Segmented poly(urethane-urea-siloxanes) (PUUS) based on 4,4?- methylene diphenyl diisocyanate-ethylene diamine (MDI-ED) hard segments and hidroxypropyl-terminated poly(dimethylsiloxane) (PDMS, M n =1000 g mol-1) soft segments were prepared under various experimental conditions. The copolymers with constant molar ratio of hard and soft segments (PDMS:MDI:ED = 1:2:1; 20 wt. % of the hard segments) were synthesized in two different solvent mixtures, by two-step polyaddition procedure. The first one was THF/DMAc with different co-solvent ratio (1/1, 1/2 and 1/9, v/v), whereas the second one was THF/NMP (1/9, v/v). The reaction conditions were optimized by varying the co-solvents ratio, the concentration of the catalyst, the initial monomer concentration, as well as the time of the first and the second step of reaction. The effect of the experimental conditions on the size of PUUS was investigated by gel permeation chromatography (GPC) and viscometry of the dilute solutions [?]. The copolymers with the highest molecular weights were obtained in the THF/NMP mixture (1/9, v/v). The structure and composition of the copolymers were determined by 1H NMR and FTIR spectroscopy. The morphology of the synthesized copolymers was investigated by atomic force microscopy (AFM), while the thermal properties were studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The surface properties were evaluated by measuring the water contact angle (WCA). The copolymers showed phase separated microstructure and were stable up to 200?C in nitrogen.
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Chen, Li-Juan, Fu-Ming Mei, and Guang-Xing Li. "Cobalt Schiff base complexes with symmetric or asymmetric ligands: syntheses and application for the redox carbonylation of aniline to diphenyl urea." Reaction Kinetics and Catalysis Letters 98, no. 1 (September 11, 2009): 99–105. http://dx.doi.org/10.1007/s11144-009-0073-6.

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39

Molnar, Maja, Harshad Brahmbhatt, Vesna Rastija, Valentina Pavić, Mario Komar, Maja Karnaš, and Jurislav Babić. "Environmentally Friendly Approach to Knoevenagel Condensation of Rhodanine in Choline Chloride: Urea Deep Eutectic Solvent and QSAR Studies on Their Antioxidant Activity." Molecules 23, no. 8 (July 29, 2018): 1897. http://dx.doi.org/10.3390/molecules23081897.

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A series of rhodanine derivatives was synthesized in the Knoevenagel condensation of rhodanine and different aldehydes using choline chloride:urea (1:2) deep eutectic solvent. This environmentally friendly and catalyst free approach was very effective in the condensation of rhodanine with commercially available aldehydes, as well as the ones synthesized in our laboratory. All rhodanine derivatives were subjected to 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) scavenging activity investigation and quantitative structure-activity relationship (QSAR) studies were performed to elucidate their structure-activity relationship. The best multiple linear QSAR model demonstrate a stability in the internal validation and Y-randomization (R2 = 0.81; F = 24.225; Q2loo = 0.72; R2Yscr = 0.148). Sphericity of the molecule, ratio of symmetric atoms enhanced atomic mass along the principle axes in regard to total number of atoms in molecule, and 3D distribution of the atoms higher electronegativity (O, N, and S) in molecules are important characteristic for antioxidant ability of rhodanine derivatives. Molecular docking studies were carried out in order to explain in silico antioxidant studies, a specific protein tyrosine kinase (2HCK). The binding interactions of the most active compound have shown strong hydrogen bonding and van der Waals interactions with the target protein.
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Platonova, Elena, Polina Ponomareva, Zalina Lokiaeva, Alexander Pavlov, Vladimir Nelyub, and Alexander Polezhaev. "New Building Blocks for Self-Healing Polymers." Polymers 14, no. 24 (December 9, 2022): 5394. http://dx.doi.org/10.3390/polym14245394.

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The healing efficiency in self-healing materials is bound by the ability to form blends between the prepolymer and curing agent. One of the problems in the development of self-healing polymers is the reduced affinity of the bismaleimide curing agent for the elastomeric furan-containing matrix. Even when stoichiometric amounts of both components are applied, incompatibility of components can significantly reduce the effectiveness of self-healing, and lead to undesirable side effects, such as crystallization of the curing agent, in the thickness and on the surface. This is exactly what we have seen in the development of linear and cross-linked PUs using BMI as a hardener. In this work, we present a new series of the di- and tetrafuranic isocyanate-related ureas—promising curing agents for the development of polyurethanes-like self-healing materials via the Diels–Alder reaction. The commonly used isocyanates (4,4′-Methylene diphenyl diisocyanate, MDI; 2,4-Tolylene diisocyanate, TDI; and Hexamethylene diisocyanate, HDI) and furfurylamine, difurfurylamine, and furfuryl alcohol (derived from biorenewables) as furanic compounds were utilized for synthesis. The remendable polyurethane for testing was synthesized from a maleimide-terminated prepolymer and one of the T-series urea. Self-healing properties were investigated by thermal analysis. Molecular mass was determined by gel permeation chromatography. The properties of the new polymer were compared with polyurethane from a furan-terminated analog. Visual tests showed that the obtained material has thermally induced self-healing abilities. Resulting polyurethane (PU) has a rather low fusing point and thus may be used as potential material for Fused Deposition Modeling (FDM) 3D printing.
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Y. Ab Hafidz, M., A. F. Mohd2, and M. Zulkifli. "Mechanical Properties and Formaldehyde Emission of Rubberwood Particleboard Using Emulsified Methylene Diphenyl Diisocyanate (EMDI) Binder at Different Press Factor Continuous Press." International Journal of Engineering & Technology 7, no. 4.14 (December 24, 2019): 335. http://dx.doi.org/10.14419/ijet.v7i4.14.27669.

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Rubberwood particleboard with low formaldehyde emission is a must in wood based paneling industry especially for export market such as in Japan, Korean, European countries and North America Region. Avoiding of urea formaldehyde binder and substitute it with emulsion isocyanate resin is an alternative in particleboard production. However, the low tackiness and sticking to steel belt during transferring and pressing in actual particleboard production contributes to surface defects as well as variation in mechanical properties of the final product. The results revealed that a correlation speed and press factor is necessary in order to improve mechanical properties and to keep the physical performance of boards within a limited range of values. Various speeds of press factors were studied at 15.0, 14.5, 14.0, 13.5 sec/mm to study the effect to the bending, internal bonding, screw withdrawal, surface soundness, thickness swelling, moisture content properties and formaldehyde emission of particleboard. At higher production speed (lower press factor), bending, internal bonding, MOE and edge screw withdrawals properties of particleboard was decrease by 3% to 13%. Thickness swelling and moisture content were increased in final particleboard production. Emission of formaldehyde was below than 0.15 mg/L (JIS A 1460) at all speeds of press factor which is extremely low.
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42

Matsuura, Satoru, Hidemasa Katsumi, Hiroe Suzuki, Natsuko Hirai, Rie Takashima, Masaki Morishita, Toshiyasu Sakane, and Akira Yamamoto. "l-Cysteine and l-Serine Modified Dendrimer with Multiple Reduced Thiols as a Kidney-Targeting Reactive Oxygen Species Scavenger to Prevent Renal Ischemia/Reperfusion Injury." Pharmaceutics 10, no. 4 (December 1, 2018): 251. http://dx.doi.org/10.3390/pharmaceutics10040251.

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l-cysteine (Cys)- and l-serine (Ser)-modified, third-generation polyamidoamine (PAMAM) dendrimer with multiple reduced thiols (Ser-PAMAM-Cys) was synthesized as a kidney-targeting reactive oxygen species (ROS) scavenger to help prevent renal ischemia/reperfusion injury. Ser-PAMAM-Cys effectively scavenged 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and ROS (hydrogen peroxide and hydroxyl radical) in phosphate-buffered saline (PBS). In addition, ~64% of 111In-labeled Ser-PAMAM-Cys accumulated in mouse kidney 3 h after intravenous administration. An in vivo imaging system (IVIS) study indicated that near-infrared fluorescence dye (NIR)-labeled Ser-PAMAM-Cys specifically accumulated in the kidney. In a mouse renal ischemia/reperfusion injury model, increases in the kidney damage markers creatinine (Cre) and blood urea nitrogen (BUN) were significantly inhibited by intravenous Ser-PAMAM-Cys administration. In contrast, Cys injection had no statistically significant effect of preventing Cre or BUN elevation relative to the control. Ser-PAMAM-Cys also effectively downregulated the inflammatory factors NGAL, IL-18, ICAM-1, and VCAM-1 in the renal ischemia/reperfusion injury model. These results indicate that Ser-PAMAM-Cys is a promising kidney-targeting ROS scavenger which could prevent ischemia/reperfusion-induced renal failure.
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43

Fu, Shun Xin, Guang Ping Han, Wan Li Cheng, and James Deng. "Modification of Wheat Straws through Steam Explosion and its Effect on Panel Properties." Advanced Materials Research 143-144 (October 2010): 1429–33. http://dx.doi.org/10.4028/www.scientific.net/amr.143-144.1429.

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Particleboards bonded with urea formaldehyde (UF) and a combination of UF and methylene diphenyl diisocyanate (MDI) resins were manufactured using wheat straws modified through different steam explosion treatments. The effect of steam explosion treatment, resin system, and mixing ratios of wood and straw materials on the panel properties was investigated. Generally, with steam explosion treatment of straw fibers, panel properties in bending and internal bond (IB) strength increased, thickness swelling (TS) and water absorption (WA) decreased. The bending properties for the panels made from the straws pretreated with 12 h water-soaking were significantly improved at the UF/MDI content level of 5%/1%. The IB strength dramatically increased, while TS and WA decreased with the use of dual resins. With increased weight ratio of wheat straw to wood particles, the bending properties, IB strength, TS and WA deteriorated. Pure wheat straw boards had the lowest properties. Wood particles in substitution for part of straw materials helped improve the panel properties. The results demonstrated that steam explosion modification and/or its combination with UF/MDI dual resin system can be a feasible approach to improve the bonding strength for wheat straw based particleboards.
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44

Lv, Hui, Shunsheng Chen, Xiaolin Xu, Manman Zhu, Wenfang Zhao, Kewu Liu, and Kehai Liu. "Isolation of Linoleic Acid from Sambucus williamsii Seed Oil Extracted by High Pressure Fluid and Its Antioxidant, Antiglycemic, Hypolipidemic Activities." International Journal of Food Engineering 11, no. 3 (June 1, 2015): 383–91. http://dx.doi.org/10.1515/ijfe-2014-0234.

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Abstract Linoleic acid was isolated effectively from Sambucus williamsii (SW) seed oil which was extracted by high-pressure fluid and its biological activities were investigated. Linoleic acid was isolated from the oil by urea inclusion, the yield was 65.81% and the purity was 92.12%. 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay was used to determine the antioxidant activity of linoleic acid. IC50 of DPPH radical scavenging activity of linoleic acid was 61.92 mg/mL. The antiglycemic activity of linoleic acid was evaluated by determining its inhibitory effect on α-glucosidase. The results showed that α-glucosidase was inhibited to a certain extent by linoleic acid (1.56–25 mg/mL). In addition, the hypolipidemic activity of linoleic acid was investigated in vivo using hyperlipidemia mice models fed with the linoleic acid at doses of 1, 2, 4 g/kg BW (body weight). The results showed that serum lipid levels were highly significantly (p<0.01) improved, which indicated the hypolipidemic activity of linoleic acid. The linoleic acid extracted from SW seed oil was proved to possess good antioxidant, antiglycemic and hypolipidemic activity in human diets, which may have industrial use.
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45

Abdollahi Baghban, Sahar, Manouchehr Khorasani, and Gity Mir Mohamad Sadeghi. "Soundproofing flexible polyurethane foams: Effect of chemical structure of chain extenders on micro-phase separation and acoustic damping." Journal of Cellular Plastics 56, no. 2 (July 25, 2019): 167–85. http://dx.doi.org/10.1177/0021955x19864387.

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In this study, a new high-performance acoustic damping flexible polyurethane foam (FPUF) was successfully designed and fabricated using synthesized linear saturated aliphatic polyester resin as polyol, methylene diphenyl diisocyanate, and ethylene glycol, monoethanolamine, and ethylenediamine as chain extenders and other reagents by one-shot bulk polymerization (isocyanate index = 100 and water content = 2.5%). The effect of the chemical structure of different chain extenders on micro-phase separation and acoustic damping properties of FPUFs were investigated using comprehensive characterization techniques such as atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FT-IR), compressive strength, optical microscope, and‏ ‏impedance tube. It was indicated that the micro-phase separation degree of the FPUF matrix increased with increasing amine content in the chain extender structure due to the more bidentate hydrogen bondings formation between urea-urea groups. Also, by increasing micro-phase separation, average cell sizes decreased and compressive strength, open-cell contents%, cell walls roughness, and cell size distribution of FPUFs increased. According to the sound absorption spectra, it was found that sound absorption efficiency of FPUF containing DEA was higher than FPUF manufactured by EG by 13.23% in the range of 1500–4000 Hz due to the increase of the amine content of chain extenders. These results indicate that the acoustic properties of FPUFs can be explained with the synergistic actions of micro-phase separation including the viscoelastic behavior of hard-soft segments and increasing of airflow pathway leading to dissipating of the kinetic energy of sound waves. Finally, the results revealed that soundproofing FPUFs with an optimum condition for micro-phase separation and drainage flow can be a promising candidate for using as sound insulating materials in transportation industries such as airplanes, trains, etc.
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46

Tripathi, Renu, Swati Agarwal, Syed Ibrahim Rizvi, and Neetu *. Mishra. "The Antioxidant Efficacy of Wheatgrass (Triticum Aestivum) on Mercuric Chloride (HgCl2) - Induced Oxidative Stress in Rat Model." Current Research in Nutrition and Food Science Journal 9, no. 2 (August 30, 2021): 450–64. http://dx.doi.org/10.12944/crnfsj.9.2.09.

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Mercury is a harmful toxic pollutant, which has hepato-nephrotoxic, hematotoxic, genotoxic and neurotoxic, effects. The aim of the study was to evaluate the protective efficacy of wheatgrass on mercuric chloride (HgCl2) induced oxidative stress and associated complications in rat model. Albino rats were divided into four groups (three rats per group). Group I normal control group. Group II oxidative stressed group received mercuric chloride (0.5 mg/kg/day). Group III only received wheatgrass extract (100 mg/kg/day), whereas Group IV received wheatgrass (100 mg/kg/day) after one hour, followed by mercuric chloride (0.5 mg/kg/day) for 30 days. The results of the study showed that wheatgrass supplementation significantly decreased the HgCl2 induced elevated oxidative stress parameters Plasma Malondialdehyde (MDA) content, Plasma membrane redox system (PMRS), Advanced oxidation protein products (AOPP), simultaneously elevated lipid profile (Total Cholesterol, Triglycerides, Low-density lipoprotein (LDL), liver enzymes as, Plasma Alkaline phosphatase (ALP), Aspartate aminotransferase (AST), and Alanine aminotransferase (ALT), Serum Urea, and Creatinine levels in rats. In addition, wheatgrass treatment improved the antioxidant status in terms of intracellular Reduced Glutathione (GSH), Ferric reducing antioxidant power (FRAP) and 2, 2- diphenyl -1- picrylhydrazyl (DPPH). Therefore it can be concluded that wheatgrass has great potential to diminish the stress-mediated complications and improve the antioxidant status.
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47

Badmus, Jelili A., Olaniyi T. Adedosu, Emmanuel G. Adeleke, Kehinde H. Akinboro, Bayonle I. Odeyemi, Bolanle I. Ayoola, and Donavon C. Hiss. "In Vitro and In Vivo Biochemical Evaluations of the Methanolic Leaf Extract of Garcinia kola." International Scholarly Research Notices 2014 (October 30, 2014): 1–9. http://dx.doi.org/10.1155/2014/391692.

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Garcinia kola Heckel (Guttiferae) leaves have received limited scientific attention despite their traditionally acclaimed medicinal properties. The scavenging ability of the methanolic leaf extract (MLE) of G. kola was assayed for hydroxyl radical (OH•), superoxide anion (O2-), 1,1-diphenyl-2-picrylhydrazyl (DPPH), azinobis-3-ethyl-benzothiazoline-6-sulfonic acid (ABTS•+), and lipid peroxidation (LP) activity in egg yolk, rat liver, and brain homogenates. Total phenolic and flavonoid contents of the extract were also evaluated. Group I animals were given oral doses of water, whereas Group II and Group III animals received 100 and 200 mg/kg body weight (bw) MLE, respectively, for 14 days. Plasma glucose, magnesium, γ-glutamyltransferase (GGT/γGT), alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine, and urea were evaluated. Hepatic reduced glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD), LP, and liver histopathological appearance were also assessed. The extract scavenged OH•, O2-, DPPH, and ABTS•+ and inhibited LP in egg yolk, rat liver, and brain homogenates. Furthermore, oral administration of the extract showed no adverse effects on hepatic and renal function tests. Increased hepatic GSH and nonsignificant changes in LP, GPx and SOD activities, and liver histology were observed. These results suggest that G. kola leaves have antioxidant activities which may have application in traditional medicine.
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48

Zhang, Yang, Yang Liu, Kun Zhu, Yao Dong, Hao Cui, Liping Mao, Xiaoxiao Xu, and Hongli Zhou. "Acute Toxicity, Antioxidant, and Antifatigue Activities of Protein-Rich Extract from Oviductus ranae." Oxidative Medicine and Cellular Longevity 2018 (2018): 1–14. http://dx.doi.org/10.1155/2018/9021371.

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The paper investigated the preparation, amino acid composition, acute toxicity, and in vitro and in vivo antioxidant, coupled with in vivo antifatigue activities of protein-rich extract of Oviductus ranae (PEOR). The results indicated that PEOR possesses high-safety property with maximum tolerated dose (MTD) higher than 20 g/kg in mice, shows weak scavenging capacities against hydroxyl, superoxide anion, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, as well as ferric-reducing antioxidant power in vitro, but exerts strong antioxidant effect in ethanol-induced oxidative stress mice model; it can decrease malonaldehyde (MDA) and protein carbonyl (PCO) formation and increase total superoxide dismutase (T-SOD) activity and glutathione (GSH) synthesis. Besides the strong in vivo antioxidant activity, PEOR in a dose of 400 mg/kg also has antifatigue effect in mice, and it can prolong the exhaustive swimming time, reduce the elevated blood urea nitrogen (BUN) and blood lactic acid (BLA) caused by intense exercise. The in vivo activity of PEOR may be contributed by its absorbed amino acids, due to the fact that eight antioxidant amino acids and twelve glucogenic ones were found in it. This study will provide an evidence for the clinical use of PEOR as a dietary supplement for antioxidant and antifatigue in the same oral dose (400 mg/kg).
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Dai, Bingling, Mengying Fan, Runze Yu, Qi Su, Bo Wang, Tianfeng Yang, Feng Liu, and Yanmin Zhang. "Novel diphenyl urea derivative serves as an inhibitor on human lung cancer cell migration by disrupting EMT via Wnt/β-catenin and PI3K/Akt signaling." Toxicology in Vitro 69 (December 2020): 105000. http://dx.doi.org/10.1016/j.tiv.2020.105000.

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Kim, Jae-Kon, Jaehong Kim, Suhee Song, Ok-Sang Jung, and Hongsuk Suh. "Enantiomeric Recognition of d- and l-Amino Acid Methyl Ester Hydrochlorides by New Chiral Bis-pyridino-18-crown-6 Substituted with Urea, and Diphenyl Groups." Journal of Inclusion Phenomena and Macrocyclic Chemistry 58, no. 1-2 (November 23, 2006): 187–92. http://dx.doi.org/10.1007/s10847-006-9143-9.

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