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Influence of the Phosphate Salts Nature on the Synthesis of Apatite in a Wet Atmosphere
Rachida Elosrouti,
Brahim Sallek,
Hassan Chaair,
Khalid Digua,
Hassan Oudadesse
Issue:
Volume 3, Issue 1, February 2015
Pages:
1-6
Received:
28 November 2014
Accepted:
17 December 2014
Published:
26 January 2015
Abstract: Hydroxyapatite (Ca10 (PO4)6 (OH)2, HAP) is widely used as a bone graft substitute, potential carriers of drugs and in the purification of proteins, et could be synthesized artificially by various methods but the hydrothermal method at low temperature, which gives a good crystallinity, is often used. Moreover, several studies have shown that, in the synthesis of calcium phosphate, the nature of the final product may differ depending on the experimental conditions including the value of the initial Ca / P ratio, the nature of the calcium salts used and influence of the residence time of the initial products used in experimental conditions. Thus, in this work, while maintaining the initial Ca / P ratio to a fixed value (1,00 ± 0,01), we followed the behavior of two initial mixtures of a calcium salt and one of two other phosphate salts (di-ammonium hydrogen phosphate and di-ammonium hydrogen phosphate) as a function of residence time in an autoclave at a temperature of 80 °C in a saturated water vapor environment. The characteristics of the final product were carried out by four methods: X-ray diffraction, infrared absorption spectroscopy in the range 400 cm-1 _ 4000 cm-1, chemical analysis, and scanning electron microscopy. The XRD analysis has shown that the products obtained have all an apatite structure. They show the presence, alongside that of apatite, the identifiable stripes of the calcite for the residence times in the experience that are less than 48 hours. Similarly, the infrared absorption spectroscopy for short residence times ranging from 2 hours to 8 am always have shown the presence of the bands specific to the CO32- ions which are fit for calcite and which decrease by increasing the residence time. Beyond this time, in the two experimental conditions, we note the total disappearance of these bands after 48 hours. Beyond 48 hours, by chemical analysis the atomic ratio Ca / P remains practically constant and equal to 1.60 ± 0.01 for salts (NH4) H2PO4 and 1.58 ± 0.01 synthesized from the salts (NH4) H2PO4 within experimental error. Also, the SEM photographs have shown the presence of a phase formed of a needle agglomerate.
Abstract: Hydroxyapatite (Ca10 (PO4)6 (OH)2, HAP) is widely used as a bone graft substitute, potential carriers of drugs and in the purification of proteins, et could be synthesized artificially by various methods but the hydrothermal method at low temperature, which gives a good crystallinity, is often used. Moreover, several studies have shown that, in the...
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Comparative Studies on in Vitro Free Radical Scavenging Activity of Aqueous, Ethanol, Ethylacetate and N-Hexane Extracts of Leaves of Datura stramonium and Ocimum gratissimum
Chintem Williams D. G.,
Nzelibe Humphrey Chukwuemeka
Issue:
Volume 3, Issue 1, February 2015
Pages:
7-12
Received:
11 September 2014
Accepted:
25 September 2014
Published:
2 February 2015
Abstract: The in vitro Free Radical Scavenging Activity of aqueous, ethanol, ethylacetate and n-hexane extracts of leaves of Datura stramonium and Ocimum gratissimum were investigated. Due to the fact that Free radicals are implicated in many diseases including diabetes mellitus, arthritis, cancer, ageing. etc. In the treatment of these diseases, antioxidant therapy has gained utmost importance. The phytochemical analysis was carried out by standard methods and the antioxidant activity of the various extracts were measured on the basis of the free radical scavenging activity of the extract on stable 1, 1-diphenyl 2-picrylhyorazyl (DPPH) at varying concentrations of the plant extracts (20, 40, 60, 80 and 100 µg/ml) and absorbance was measured at 517nm using UV-Vis spectrophotometer. The results indicated that alkaloids, flavonoids, terpenoids, steroids and tannins were present in D. stramonium ethanol leaf extract while alkaloids, flavonoids, terpenoids and steroids were present in O. gratissimum n-Hexane leaf extract. The percentage inhibition of the solvent extracts at 100 μg/ml - aqueous (30.77 %), ethanol (74.90 %), ethylacetate (49.94 %) and n-hexane (69.90 %) for D. stramonium while for O. gratissimum - aqueous (45.84 %), ethanol (49.47 %), ethylacetate (63.94 %) and n-hexane (91.14 %). Of all the extracts, n-hexane leave extract of O. gratissimum exhibited the highest free radical scavenging activity with IC50 0.21 μg/ml compared to ethanol leave extracts of D. stramonium with IC50 0.29 μg/ml. This study revealed that n-hexane leaf extract of Ocimum gratissimum had a more potent antioxidant activity compared to the ethanol leaf extract of D. stramonium which had moderate antioxidant activity. Both plants extracts had no significant difference when compared with ascorbic acid standard (0.19 µg/ml) at (P≤.05). The phytochemical profile of the plants might be responsible for their high antioxidant activity, thus justifying wide use of O. gratissimum in diet which could provide a source of high dietary antioxidants and D. stramonium in ethno-botanical applications.
Abstract: The in vitro Free Radical Scavenging Activity of aqueous, ethanol, ethylacetate and n-hexane extracts of leaves of Datura stramonium and Ocimum gratissimum were investigated. Due to the fact that Free radicals are implicated in many diseases including diabetes mellitus, arthritis, cancer, ageing. etc. In the treatment of these diseases, antioxidant...
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Susceptibility of Vegetatively Propagated Khaya anthoteca to Arbuscular Mycorrhizae Fungi (AMF) Soil Inoculum Infection
Philip Worlanyo Dugbley,
Irdika Mansur,
Basuki Wasis
Issue:
Volume 3, Issue 1, February 2015
Pages:
13-18
Received:
3 August 2014
Accepted:
19 August 2014
Published:
15 February 2015
Abstract: Stem tip cuttings of Khaya anthoteca seedlings were experimented for the trapping of Arbuscular Mycorrhizae Fungi (AMF). This study aimed to determine the effect of hormone and wounding treatments on the vegetative propagation of K. anthoteca seedlings and the susceptibility of these cuttings to AMF soil inoculums infection compared to some other bait species such as Sorghum bicolor and Puereria javanica. The results indicated that, K. anthoteca can successfully be propagated through stem cutting with only wounding and without hormone (auxin) applications. Analysis of variance tested at 5% significance level revealed no differences between the treatment means of hormone and wounding on the number of roots. Again, the lengths of the longest roots were not significantly different over the control treatment. In the trapping experiment, there were no significant differences in terms of root segment colonization between K. anthoteca cuttings and the other trapping species. This observation was however, frequent in the young and meristematic segments of the roots for K. anthoteca. An average root colonization of 32% was observed for K. anthoteca and the highest recorded by S. bicolor of 43%. Thus, about a third of root segments of K. anthoteca were colonized by AMF. There was also a significant positive correlation between percentage root segment colonization and the number of counted spores. The study concludes that wounding of K. anthoteca six-month old seedlings prior to vegetative propagation by cutting play vital role with respect to the rooting ability of the propagules compared to non-wounded propagules and also not significantly different from that of synthetic hormone application. Again, K. anthoteca is susceptible to AMF just like most tropical plant species in Indonesia. Finally, AMF soil inoculums can also be a good source of inoculants for establishing K. anthoteca in areas of degraded lands for revegetation purposes.
Abstract: Stem tip cuttings of Khaya anthoteca seedlings were experimented for the trapping of Arbuscular Mycorrhizae Fungi (AMF). This study aimed to determine the effect of hormone and wounding treatments on the vegetative propagation of K. anthoteca seedlings and the susceptibility of these cuttings to AMF soil inoculums infection compared to some other b...
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Thermal Time Utilization of Plum in Semi Arid Region of Gangetic Plain
Issue:
Volume 3, Issue 1, February 2015
Pages:
19-24
Received:
15 January 2015
Accepted:
6 February 2015
Published:
15 February 2015
Abstract: Plum prefers temperate climate thus a major crop of hills however, it has been found growing from higher hills in Srinagar to Jaipur in Rajasthan and areas around Delhi. It requires less chilling hours and can tolerate frost and high summers both, that is why it can be cultivated in both low temperatures to 0°C and up, highest up to 47°C in summers. Among the major Japanese cultivar the Kala Amritsari, Satluj Purple and Titron are planted at HAU farm in 2001 on which the present study was done during 2013-14. The overall growth was observed better in Kala Amritsari followed by Satluj purple and Titron which is a late maturing variety. The thermal time required by Kala Amritsari and Satluj Purple was at par but the Titron required more thermal indices. The heat use efficiency was observed highest for Kala Amritsari and lowest for Titron whereas the photothermal index was highest in Titron followed by Kala Amritsari and Satluj Purple. The thermal units explained the 94 per cent variation in fruit yield of Kala Amritsari, 87 per cent variation in Satluj Purple and 83 percent variation in fruit yield of Titron cultivar.
Abstract: Plum prefers temperate climate thus a major crop of hills however, it has been found growing from higher hills in Srinagar to Jaipur in Rajasthan and areas around Delhi. It requires less chilling hours and can tolerate frost and high summers both, that is why it can be cultivated in both low temperatures to 0°C and up, highest up to 47°C in summers...
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Optimum Design and Simulation of Structure Parameters of Pantograph Based on Equivalent Mass
Zhang Shufeng,
Yang Jian,
Song Ruigang,
Yuan Tianchen
Issue:
Volume 3, Issue 1, February 2015
Pages:
25-29
Received:
15 January 2015
Accepted:
22 January 2015
Published:
15 February 2015
Abstract: Based on the mathematical model of geometric relations of high-speed single-arm pantograph, structure parameters of the high-speed single-arm pantograph are optimized and designed applying multi-objective Optimization technology. Considering good contact of pantograph-catenary, rising height of pantograph and time of rising and dropping pantograph as the constraint condition, and considering the trajectory of pantograph head and the equivalent mass of pantograph as the target, a group of optimal structural parameters are gained combining with MATLAB software. The three-dimensional modeling of pantograph is completed according to the results of optimization. Applying virtual prototype technology to simulated analysis can verify the precision of the optimization results and methods.
Abstract: Based on the mathematical model of geometric relations of high-speed single-arm pantograph, structure parameters of the high-speed single-arm pantograph are optimized and designed applying multi-objective Optimization technology. Considering good contact of pantograph-catenary, rising height of pantograph and time of rising and dropping pantograph ...
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