204 research outputs found

    Assessment of Innovation Strategy and Commercialization to Enhance Mango Value Chain: A Case Study of South-Western Nigeria

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    This study assessed the innovation developed to enhance mango value chain. Purposive sampling procedure was used to select one research institute, one university with a commercial farm and one commercial enterprise to determine the level of commercialization of research products and innovations for social and economic development. The selected institutions were Afe Babalola University Ado-Ekiti (ABUAD FARMS), National Horticultural Research Institute and FUMMAN Agricultural Products Limited. Results showed that the factors that determined the quantity of mango produced were; income realised on past production, accessibility to information on better production practices, educational qualification of respondents and size of land cultivated. Notable constraints attributed to low production of mango plantation among the respondents were bad road networks, high cost of pesticides, and lack of credit facilities and shortage of grafted seedlings. Adopters of improved variety of mango had more quantity of production than the non-adopters of improved variety of mango. Keywords: Enabling environment, Research results, Innovation, Mango and Developmen

    Effects of substituents and solvents on the photochemical properties of zinc phthalocyanine complexes and their protonated derivatives

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    Zinc phthalocyanine derivatives containing various ring substituents and axial ligands were studied with respect to the effect of substituents on protonation. Aggregation resulted in failure of some of the ZnPc derivatives to protonate. In fact addition of protonating agents to aggregated ZnPc derivatives resulted in increase in aggregation followed by slow degradation. Axial ligands were lost on protonation. Photobleaching, fluorescence and singlet oxygen quantum yields of the protonated derivatives were compared with those of the unprotonated derivatives. In all cases protonation decreases the singlet oxygen and fluorescence quantum yields. However, photobleaching quantum yields decreased (i.e. stability increased) for the protonated derivatives except when axial ligands were present, where protonation resulted in decrease in stability

    Performance response, carcass evaluation and economic benefit of rabbits fed sorghum offal-based diets

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    An eight-week feeding trial was conducted to investigate the performance, carcass quality, haematological indices and economics of production of rabbits fed dietary sorghum offal substitute for maize grain. A total of forty (40) weaned rabbits with a mean weight range of 820-850 g were randomly distributed to five treatment diets where 0, 25, 50, 75 and 100% of sorghum offal replaced maize grain in the gross feed composition to give Diets 1 (control), 2, 3, 4 and 5, respectively. Each treatment diet was replicated eight times with a rabbit taken as a replicate. The determined chemical composition of the experimental diets ranged between 17.12% and17.43% for crude protein (CP), 11.48 and 14.89% for crude fibre (CF), 5.04 and 7.74% for ether extract or fat (EE), 54.17 and 56.41% for  nitrogen free extract (NFE) and 3069.35kcal/kg to 3241.17ME(kcal/kg). While the results on performance showed no significant difference (P>0.05) in feed intake by rabbits fed the five test diets, there appeared to be significant decrease (P<0.05) in the weight gain and feed conversion ratio of rabbits fed 50 to 100% sorghum offal-based diets. Carcass cuts that showed significant reduction (P<0.05) at 75 and 100% sorghum offal-based diets are the carcass weight, thigh, loin, shoulder and ribs weights. Organs such as liver, kidney, heart and pancreas weights  measured were significantly higher (P<0.05) at 75 and 100% sorghum offal-based diets. Haematological profile such as Packed Cell Volume(PCV), Red Blood Cells (RBC), White Blood Cells (WBC), Mean Cell Volume(MCV) and White Blood Counts such as neutrophil and basophil showed significant difference (P<0.05) at 75% and 100% sorghum offal-based diets. The serum metabolites such as albumin, globulin, cholesterol and urea showed a similar trend of significant difference (P<0.05) at 75% and 100% sorghum offal inclusion compared to other test diets. For economic production, the study revealed an optimum inclusion of sorghum offal at 50% (24.60 g/kg in feed composition) for maize grain in rabbit concentrate feed is possible. Above this level, a loss of N23.17 and N13.16 was recorded as evidenced by the cost differential and benefit cost analysis.Key words: Performance, Haematology, Serum, Sorghum offal, Rabbi

    Performance and economic consideration of broiler chickens fed enzyme supplemented cassava fibre meal

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    The search for alternative energy source to substitute for the expensive conventional energy feed resources in broiler chicken diet is the driving force of this study. Thus, the study assessed the performance and economics of the production of broiler chickens fed enzyme supplemented cassava fibre meal (CFM) in a 56-day feeding trial. A batch of three hundred and sixty (360) day-old Arbor acre broiler-chicks was allotted to twelve (12) diets replicated five (5) times of six (6) birds in a complete randomization. Cassava fibre was sun dried for 5 days with constant turning to prevent fermentation, reduce the moisture content and possibly reduce the cyanide content. Proximate composition, phytochemical components and cyanide contents were determined using appropriate standard methods. Cassava fibre meal was substituted for maize at 0, 20, 40, and 60% levels and Roxazyme® G2 supplementation was at 0, 100 and 200 mg/kg. Data collected on feed intake and weight gain were analysed using the General Linear Model (GLM), and differences in means where observed were separated using Duncan option of the SPSS 2006 version 15.0. The Economics of broiler chicken production was determined using economic tools such as gross margin and economic efficiency analyses. Results showed that CFM contained appreciable levels of nutrients that could promote broiler growth when substituted at optimum level as an energy source in broiler chicken diet. Substitution of CFM at 40 and 60% levels for maize led to a decrease (p<0.05) in weight gain and feed conversion of broiler chickens. Feed intake and weight gain were not influenced by dietary substitution of CFM for maize in the broiler starter and broiler finisher stages of growth. The effect of enzyme supplementation was not significant in the birds’ physiological growth at both starter and finisher stages. The effect of interaction was not significant (p>0.05) indicating that birds’ performance were not dependent on the two factors under investigation. Economics of broiler chicken production revealed that total cost was lower in birds fed CFM with or without enzyme supplementation compared with those fed the maizebased diets. Net revenue, economic efficiency and profitability ratio analysis showed better economic viability and profitability in birds fed CFM with or without enzyme supplementation compared with those fed maize-based diets

    Effects of central metal on the photophysical and photochemical properties of non-transition metal sulfophthalocyanine

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    The photophysical and photochemical properties and quenching (by 1,4-benzoquinone) of metallophthalocyanine sulfonates of aluminium (AlPcSmix), zinc (ZnPcSmix), silicon (SiPcSmix), germanium (GePcSmix) and tin (SnPcSmix) are presented. The quantum yield values of fluorescence (ΦF), triplet state (ΦT), singlet oxygen (ΦΔ) and photodegradation (Φd) were determined and the observed trends in their variation among the complexes discussed in terms of aggregation and the heavy atom effect. 1,4-benzoquinone effectively quenched the fluorescence of the complexes. Quenching analyses gave positive deviations from Stern-Volmer behavior, suggesting the existence of static quenching in addition to dynamic quenching. The static and dynamic components of the quenching were separated using a modified Stern-Volmer equation and the “sphere of action quenching model”. The quenching constant was found to be a function of the radius of the central metal ion

    Photophysical and photochemical studies of non-transition metal phthalocyanine derivatives

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    A detailed photophysicochemical study of some non-transition metal (AI, Zn, Si, Ge, and Sn) metallophthalocyanine (MPc) derivatives is presented. The effects of substituents, central metal ions and solvents on the photophysical and photochemical properties are investigated and rationalized accordingly. The presence of peripheral substituents on the macrocycle enhances the yield of the triplet state. Near infra-red absorptions of the solvents reveal that solvents which absorb around 1100 nm and around 1270 nm, quench the triplet state of the MPc derivative and singlet oxygen, respectively. Although water has a high singlet oxygen quenching effect, the singlet oxygen quantum yield (Φ∆) value for sulphonated zinc phthalocyanine in water is still reasonably high at 0.48, which may provide an explanation for the efficient photosensitization by this molecule in photodynamic studies. The lowering of Φ∆ following protonation of the MPc macrocycle is attributed to the lowering of triplet energy to the level where energy transfer to ground state oxygen is no longer favourable. MPc inclusion complexes with cyclodextrins showed larger Φ∆ values when compared to the complexes before inclusion. Job's plots show that 2:1 and 4:1 (CD:MPc) complexes may be formed. Fluorescence quenching by electron donors and acceptors were analysed by StemVolmer relationship and the results used in determining fluorescence lifetimes of the complexes. Qualitative and quantitative interpretations of the interaction of sulphonated MPcs with bovine serum albumin (BSA) are provided in this thesis. 1:1 adducts were formed with BSA, but the binding feasibilities varied markedly. Spectral, photophysical and photochemical properties of the complexes are altered in the presence of BSA

    Photophysical and photochemical studies of sulphonated non-transition metal phthalocyanines in aqueous and non-aqueous media

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    The photophysical and photochemical parameters for mixed sulphonated metallophthalocyanine complexes (AlPcSmix, SiPcSmix, GePcSmix, SnPcSmix, and ZnPcSmix) are reported in phosphate buffer saline (PBS, pH 7.4), PBS containing the surfactant Triton X-100, and in dimethylsulphoxide (DMSO). The ground state spectra of SiPcSmix, GePcSmix and SnPcSmix show splitting of the Q-band in DMSO, but the fluorescence spectra have only one band, suggesting that only some components of the mixed complexes fluoresce. In general the quantum yields of fluorescence (ΦF) were smaller in DMSO compared to the aqueous solvents, while quantum yields of triplet state (ΦT) were larger in DMSO. Triplet lifetimes were much lower in aqueous solutions (compared to DMSO) due to the fact that water absorbs strongly around 1108 nm, which corresponds to the triplet energy of a metallophthalocyanine complex. The MPcSmix complexes quenched hydroquinone, and the Stern–Volmer constants follow the order: AlPcSmix > SiPcSmix > GePcSmix > ZnPcSmix > SnPcSmix which is the order of the extinction coefficients (of the low energy band for complexes with split Q-band) of these molecules. The rate constants for fluorescence, intersystem crossing, internal conversion, and photodegradation were determined from the hydroquinone quenching data

    Syntheses and photophysics of new phthalocyanine derivatives of zinc, cadmium and mercury

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    The syntheses of novel tetra{2,(3)-pyridyloxyphthalocyaninato} complexes of zinc, cadmium and mercury (TPyZnPc, TPyCdPc and TPyHgPc) are presented. Their spectral and photophysical properties (as well as those of their unsubstituted counterparts: ZnPc, CdPc and HgPc) are investigated. TPyZnPc and TPyCdPc are aggregated in non-coordinating solvents such as chloroform, while TPyHgPc is demetallated, as evident from their respective absorption spectra. The trends in fluorescence (ΦF), triplet (ΦT) and singlet oxygen (ΦΔ) quantum yields are explained in terms of relative strengths of spin–orbit coupling induced by the respective central metal ions in the complexes. The effect of the pyridyloxy substituents is a decrease in ΦF and an increase in ΦT values. The complexes are less fluorescent in DMSO but possess higher ΦT, triplet lifetimes (τT) and ΦΔ therein

    The syntheses, characterization and fluorescence spectra of novel, octakis (alkylthiophthalocyanato) nickel (II) and palladium (II) complexes

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    The syntheses, characterization and fluorescence studies of several {octakis(alkylthio)phthalocyanato} palladium(II) and nickel(II) complexes are presented. The absorption spectra of some of the complexes showed extra peaks which are attributable to non-planar distortion, the extent of which, was found to dependent on alkyl chain length. The fluorescence excitation spectra of the nickel(II) derivatives were not in agreement with their absorption spectra, owing to structural changes upon excitation. Fluorescence quantum yields were very low (more than 1%) for all complexes as a consequence of the open-shell electronic structures of nickel(II) and palladium(II)

    Photophysical, photochemical and bovine serum albumin binding studies on water-soluble gallium (III) phthalocyanine derivatives

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    Spectral, photophysical, photochemical and bovine serum albumin binding studies on some gallium(III) derivatives - {1,(4)-(tetrapyridyloxyphthalocyaninato)gallium(III), (αGaPc); 2,(3)-(tetrapyridyloxyphthalocyaninato)gallium(III), (βGaPc); and their quaternized derivatives: QαGaPc and QβGaPc)} are hereby presented. β-Substituted complexes are more fluorescent, but show lower tendencies to undergo intersystem crossing than the α-substituted, as judged by their fluorescence and triplet quantum yield values. The quaternized derivatives (QGaPc) are water-soluble and non-aggregated, which makes them potential photosensitizers of choice for photodynamic therapy applications; these amphiphilic compounds also bind strongly to bovine serum albumin in 1:1 stoichiometries, and with binding constants (Kb) in the order of 106 M−1
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