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51.
This article focuses on providing a systematic review on various fundamental properties of composite based on poly(α-hydroxy esters) and hydroxyapatite (HAp) for application in bone tissue engineering. Poly(α-hydroxy esters), a well-known synthetic biopolymer has attracted considerable interest to be employed for synthesis of bone graft substitute material with HAp mainly due to its bioresorbability, variable biodegradation rate and melt-processibility. Such features are simultaneously attractive for both biomedical application and industrial-scale productions. Besides the main function of hydroxyapatite as bioactive ceramic filler in composite to induce new bone formation upon polymer bioresorption, HAp can also serve as reinforcement for matrix polymer by providing sufficient mechanical support for cell attachment. Moreover, HAp plays a significant role in determining other composite properties, such as resistance to ingress of body fluid, body temperature ageing, relaxation movement of polymer segment, and in vivo biodegradation. These properties constitute as the fundamental requirements in field of bone tissue regeneration which is desirable to be achieved by unique composite system based on poly(α-hydroxyesters) and HAp particles. 相似文献
52.
Mohamad Faizal Ibrahim Suraini Abd-Aziz Mohamad Nafis Abdul Razak Lai Yee Phang Mohd Ali Hassan 《Applied biochemistry and biotechnology》2012,166(7):1615-1625
Acetone–butanol–ethanol (ABE) production from renewable resources has been widely reported. In this study, Clostridium butyricum EB6 was employed for ABE fermentation using fermentable sugar derived from treated oil palm empty fruit bunch (OPEFB). A
higher amount of ABE (2.61 g/l) was produced in a fermentation using treated OPEFB as the substrate when compared to a glucose
based medium that produced 0.24 g/l at pH 5.5. ABE production was increased to 3.47 g/l with a yield of 0.24 g/g at pH 6.0.
The fermentation using limited nitrogen concentration of 3 g/l improved the ABE yield by 64%. The study showed that OPEFB
has the potential to be applied for renewable ABE production by C. butyricum EB6. 相似文献
53.
54.
Anwar Usman Ibrahim Abdul Razak Hoong‐Kun Fun Suchada Chantrapromma Yan Zhang Jian‐Hua Xu 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(9):o543-o544
In the title compound, C24H17NO2S, the dioxine and thiazoline rings are distorted from planarity towards a half‐chair and an envelope conformation, respectively. The configurations of the dioxine ring, the thiazoline ring and the attached phenyl ring are conditioned by the sp3 state of the two bridgehead C atoms. The phenanthrene system is nearly coplanar with the dioxine ring, while the attached phenyl ring is orthogonal to the thiazoline ring. 相似文献
55.
Qingli Hao Fangfang Jian Xujie Yang Xin Wang Ibrahim Abdul Razak S. Shanmuga Sundara Raj Hoong‐Kun Fun 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):1431-1432
In the title complex, [Ni(Im)6](iPr‐dtp)2 or [Ni(C3H4N2)6](C6H14O2PS2)2, the coordination around the Ni atom, located on an inversion centre, is octhahedral with all positions being occupied by tertiary N atoms of the imidazole moieties. Hydrogen bonds link the anions and cations into a two‐dimensional network in the bc plane. 相似文献
56.
Suchada Chantrapromma Hoong‐Kun Fun Ibrahim Abdul Razak Nisakorn Saewon Chatchanok Karalai Kan Chantrapromma 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):e598-e599
In the title compound, C19H20O8, the benzene rings are nearly perpendicular to each other [dihedral angle 80.2 (2)°]. The carboxy group is twisted out while both the methoxy and acetyl groups are almost coplanar with their attached benzene rings. The hydroxy group is involved in an intramolecular O—H?O hydrogen bond with the acetyl O atom and the compound is connected through an intermolecular O—H?O contact to form a dimer. The crystal structure is stabilized by intermolecular O—H?O hydrogen bonds. 相似文献
57.
Hui Shun Chin Kuan Yew Cheong Khairunisak Abdul Razak 《Journal of nanoparticle research》2011,13(7):2807-2818
Antimony trioxide (Sb2O3) nanoparticles with particle size range from 2 to 12 nm were successfully synthesized by chemical reducing method. Antimony trichloride was reduced by hydrazine with the presence of sodium hydroxide (NaOH) as catalyst in ethylene glycol at 120 °C for 1 h. Effects of hydrazine concentration ([N2H5OH]/[Sb3+] = 0.75, 5, 10, 20, and 30, when concentration of NaOH was fixed [NaOH]/[Sb3+] = 3) and NaOH concentration ([NaOH]/[Sb3+] = 0, 1, 3, and 5, when concentration of hydrazine was fixed [N2H5OH]/[Sb3+] = 10) on the particle size and shape of the Sb2O3 nanoparticles were investigated. Transmission electron microscope, selected area electron diffraction pattern, and high resolution electron microscope were employed to study the morphology and crystallinity of the nanoparticles. It was observed that the particle size decreased and remained constant when [N2H5OH]/[Sb3+]) ≥ 10 and [NaOH]/[Sb3+] = 3. Further study on the crystallinity and phase of the nanoparticles was assisted by X-ray diffractometer (XRD). XRD revealed a cubic phase of Sb2O3 (ICDD file no. 00-043-1071) with preferred plane of (622) and lattice spacing of 1.68 Å. Correlation between UV–visible absorption wavelengths of the nanoparticles and their sizes was established. 相似文献
58.
Anwar Usman Ibrahim Abdul Razak Hoong‐Kun Fun Suchada Chantrapromma Bao‐Guo Zhao Jian‐Hua Xu 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o57-o58
In the title compound, C26H22O4, the pyranone ring adopts a twisted boat conformation, while the cyclohexane ring is close to an envelope conformation. The dihedral angle between the mean planes of the coumarin and naphthalene systems is 78.8 (1)°. The attached phenyl ring is in an equatorial position with respect to the cyclohexane ring. 相似文献
59.
Fangfang Jian Lude Lu Xin Wang S. Shanmuga Sundara Raj Ibrahim Abdul Razak Hoong‐Kun Fun 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):939-940
In the crystal structure of the title complex, [Au(C7H14NS2)(C18H15P)2]·C4H10, the Au atom is in a distorted tetrahedral environment consisting of the two P atoms of the triphenylphosphine ligands and the two S atoms of the diisopropylthiocarbamate ligand. The molecular structure and packing are stablized by van der Waals interactions. 相似文献
60.
Basri M Samsudin S Ahmad MB Razak CN Salleh AB 《Applied biochemistry and biotechnology》1999,81(3):205-217
Lipase from Candida rugosa was immobilized by entrapment on poly(N-vinyl-2-pyrrolidone-co-2-hydroxyethyl methacrylate)(poly[VP-co-HEMA]) hydrogel, and divinylbenzene was the crosslinking agent.
The immobilized enzymes were used in the esterification reaction of oleic acid and butanol in hexane. The activities of the
immobilized enzymes and the leaching ability of the enzyme from the support with respect to the different compositions of
the hydrogels were investigated. The thermal, solvent, and storage stability of the immobilized lipases was also determined.
Increasing the percentage of composition of VP from 0 to 90, which corresponds to the increase in the hydrophilicity of the
hydrogels, increased the activity of the immobilized enzyme. Lipase immobilized on VP(%):HEMA(%) 90∶10 exhibited the highest
activity. Lipase immobilized on VP(%):HEMA(%) 50∶50 showed the highest thermal, solvent, storage, and operational stability
compared to lipase immobilized on other compositions of hydrogels as well as the native lipase. 相似文献