Abstract A general method is presented for the spectrophotometric determination of silicon at tra... more Abstract A general method is presented for the spectrophotometric determination of silicon at trace levels. It involves the extraction of the yellow silicomolybdate with isoamyl alcohol and subsequent reduction to silicomolybdate blue. The method covers the range 0.2–15 μg of silicon. A comprehensive study of interferences using standard additions of 5 and 10 μg of silicon was carried out and many modifications are incorporated to permit the determination of silicon in a wide variety of metals and salts.
The interest in utilization of botanical insecticides, particularly essential oils have become in... more The interest in utilization of botanical insecticides, particularly essential oils have become increasingly relevant in the control of insect pests. Many plant products and their bioactive compounds with repellent, antifeed stored product insect pests have been reported however, their levels of control are still wanting. The major issue is that the oil yields obtained are low, unstable and high costs involved in production to use on a commercial scale. Use of these oils in combinations or in formulations with botanical actives as synergists or stabilizers, may make them economically viable insecticides. evaluating plant extracts (Black pepper seeds, Nutmeg seeds, coriander leaves and roots) as potential synergists in formulations with pyrethrins for possible use in protection of synergism experiments were carried out on synergists at ratio 1:1 (synergist: pyrethrins) Topical application of synergist/ formulation on completely Randomized Design layout controlled laboratory conditions of 27 ± 2 hours. Probit analysis was used pyrethrins and mais formulations of synergist: pyrethrins, coriander leaves extract (CLHE), Nutmeg seed extract (NMHE) and Black pepper seed methanol extract (BPSME) were statistically significant (P 12.02%) mortality followed by CLHE (46.67 ± 3.33%), BPSME (43.33 ± 6.67%). BPSME and NMHE co PBO, BPSHE and CLHE values were above 20. Plant extracts BPSHE and CLHE and PBO synergized th exposure duration with co additive in the formulation and only a synergist at 20,000ppm while NMHE was antagonistic to pyrethrins. correspond to pyrethrins formulations at lower concentrations c average percentage mortalities will not be different from that of higher concentrations and CLHE c for 72 h duration.
Asian Journal of Current Engineering and Maths, 2013
We apply the notion of Banach space operator ideals in nuclear spaces through topological vector ... more We apply the notion of Banach space operator ideals in nuclear spaces through topological vector spaces. The motivation for this study came from attempts to generalize the structure of nuclear spaces as a result of nuclear maps from functional analysis context. The compact closed structure associated with the category of relations results to nuclear ideals. Basic properties of Banach space operator ideals in relation to the structure of nuclear spaces will be demonstrated. We therefore establish a close correspondence between Banach space operator ideals and nuclear ideals through topological vector spaces. Mathematics Subject Classification: 46A03, 46A22, 46B50.
The present study describes a simple, selective, rapid and economical method for the determinatio... more The present study describes a simple, selective, rapid and economical method for the determination of iron (III) in its synthetic alloys using 3-hydroxy -3phenyl-1(2,4,6tribromophenyl) triazene as metallochromic indicator in the PH and temperature range of 2.5-3.0 and 20 − 600c respectively. The colour and shape of the synthesized indicator was light yellow shinning needles having melting point of 590c. It was crystallized from ethanol. The results of elemental study showed that, the values of C, H, N obtained experimentally agrees very well with those obtained theoretically. The colour at the end point changes from violet to light yellow using EDTA as a titrant. There is no interference in either determination from common metal and anion ions other than Pb(II), Cr(II), Mo(VI), Mn(II), U(vI), Cu(II), Cd(II), F−, PO4, C2O4, HPO4. Reproducible and accurate results are obtained for 5.59 -1.12mg of Iron with relative error less than ±1.79% and standard deviation not more than 0.10%. The...
African Journal of Environmental Science and Technology, 2016
The applications of various clayey minerals are related to their structural, physical and chemica... more The applications of various clayey minerals are related to their structural, physical and chemical characteristics. The physical and chemical properties of the clayey minerals dictate their utilization in the process industries and beneficiation required before usage. The study aimed at establishing the potentiality of clayey minerals from the study area, and the possibility of exploring and exploiting them in order to spur industrial development and promote economic self reliance of Kenya as a nation. The plasticity, particle size, surface area, chemical and mineralogy composition, morphological, thermal analysis and other physical properties were studied using various techniques. The clay samples composed of albite (5-16.7%), kaolinite (11.4-36.2%), microcline (15.2-35.3%), quartz (24.3-68.1%), hornblende (7.6% in samples from Ngamwa only), and other mineral impurities in small amounts. Ngamwa clayey materials consist of high impurities of chemical oxides such as TiO 2 , MnO, MgO and Fe 2 O 3. Generally, quartz and iron were the major impurities present in the samples from the concerned sites. The findings shows that clayey minerals from the study area can be exploited for commercial production of ceramic products after beneficiation using low cost and environmental friendly techniques in order to reduce the levels of iron, quartz, and other impurities to acceptable levels.
The Banach space operator ideals and nuclear maps have a large class of morphisms which behave as... more The Banach space operator ideals and nuclear maps have a large class of morphisms which behave as if they were part of a compact closed category, that is, they allow one to transfer variables between the domain and the codomain. We use the concept of nuclearity in functional analysis to establish application aspect of Banach space ideal properties in the transmission of image over wireless network based on the embedded system.
African Journal of Environmental Science and Technology, 2015
Clay samples from Tharaka-Nithi County in Kenya were characterized by hydrometer, X-ray fluoresce... more Clay samples from Tharaka-Nithi County in Kenya were characterized by hydrometer, X-ray fluorescence spectroscopy (XRF), atomic absorption spectroscopy (AAS), TGA, scanning electron microscopy (SEM) and powder diffraction (XRD) methods. The F-test and t-test were used to interpret the results. The major oxides present were Al2O3, SiO2 and the minor ones were CaO, TiO2, MnO, Fe2O3, K2O, MgO and Na2O. The values of SiO2 were greater than those of Al2O3, indicating that the samples were of clay minerals. The clay minerals with low cation exchange capacity (CEC) were present in the samples. The Atterberg limits showed that the inorganic clays of either low or intermediate plasticity having low contents of organic matter were present in the samples. The analysis further showed the availability of essential elements necessary for plant growth. The TGA analysis indicated that the decomposition of clay samples occurred in four steps. The scanning electron microscope photographs revealed tha...
Research Journal of Life Sciences, Bioinformatics, Pharmaceutical and Chemical Sciences, 2020
New metallochromic indicators belonging to the class of hydroxytriazenes has been evaluated for t... more New metallochromic indicators belonging to the class of hydroxytriazenes has been evaluated for the direct complexometric determination of Zinc in the presence of diverse ions. Reagent no (i), (ii) and (iii) has been found to be excellent indicators in the titration with EDTA at pH 6.95-7.50, 6.90-7.60 and 7.00-7.50 respectively. The colour at the end point was from light green to colourless and the titration was carried out between temperature range of 20-60C. Cl, Br,CH3COO , CO3 , SO4 , NO2 , SO3 , F, NO3 , I, S, WO4 , MO7O24 , NH4 , Na, K, U(VI), Mn(II), Ba(II), Hg(II), Sn(II), Cd(II), Mg(II), Ca (II), Zr(IV) can be tolerated in the titration of zinc (II) when they are present in equivalent amount with that of zinc (II). However, PO4 , Co (II), Cu (II) and Ni (II) interferes and when present in the environmental samples, separation techniques such as masking and demasking agents must be employed. The utility of the technique was checked by using 3-Hydroxy-3-m-toly-1-0-Carboxyphen...
Geophagy is the deliberate consumption of soil and clay deposits by animals, including man. Durin... more Geophagy is the deliberate consumption of soil and clay deposits by animals, including man. During pregnancy all the nourishment needed by the developing fetus comes from the mother, either the food she eats or the supplement she may take. The geochemical and mineralogical composition of the materials which are consumed by pregnant women from Meru, Embu and Chuka open air markets were studied. The geophagic materials were subjected to standard digestion procedures and analyzed for full assay and elemental analysis for Co, Zn, Mg, Cu, Pb and Cd using Atomic absorption spectrometry and Energy-dispersive x-ray fluorescence spectrometry in 30 geophagic samples. The mineralogical composition was investigated using X-ray diffractometry (XRD). The geochemical analysis revealed that the geophagic materials contain high levels of silica from 48.59 to 60.27%. Geophagic materials from Embu showed the highest concentration of Pb at 0.96 ppm. The levels of Pb in all samples exceeded the levels recommended by WHO/FAO limits of 0.01 ppm. The levels obtained for Cd in all the samples did not exceed the WHO/FAO limits of 0.003 ppm. The XRD data showed that the geophagic materials of the area consisted mainly of silica.
A simple, rapid and reasonable selective Complexometric technique for nickel (II) determination u... more A simple, rapid and reasonable selective Complexometric technique for nickel (II) determination using some selected hydroxytriazene as a metallochromic indicator is reported in the present study. The colour change at the end point was from greenish-yellow/yellow to colourless with sharp end point. The pH ranges were 9.3-9.7, 9.0-9.5, 8.5-9.0, 8.0-8.5 while temperature ranges were 25-60, 25-60, 25-60, 25-50 and 25-50 0C for reagent (i), (ii), (iii), (iv), and (v) respectively. Nickel(II) was determined accurately up to concentration as low as 3.0x10-3M for reagents (ii), (iv), and (v)) while for reagents (i) and (iii) the concentration range could be even lowered to 1.0x10-3M for the determination of nickel (II). The ions such as Cl-, Br-, CH3COO, CO3, PO4, SO4, C2O4, S2O3, NO2-, SO3, S2-, HPO4, F-, NO3, WO4, MO7O24, I-, NH4, Na+, K+ did not show any interference in the determination of nickel (II) even when they were present in tenfold excess. Ba2+, Mg2+, Ca2+, were tolerated up to ...
Abstract A general method is presented for the spectrophotometric determination of silicon at tra... more Abstract A general method is presented for the spectrophotometric determination of silicon at trace levels. It involves the extraction of the yellow silicomolybdate with isoamyl alcohol and subsequent reduction to silicomolybdate blue. The method covers the range 0.2–15 μg of silicon. A comprehensive study of interferences using standard additions of 5 and 10 μg of silicon was carried out and many modifications are incorporated to permit the determination of silicon in a wide variety of metals and salts.
The interest in utilization of botanical insecticides, particularly essential oils have become in... more The interest in utilization of botanical insecticides, particularly essential oils have become increasingly relevant in the control of insect pests. Many plant products and their bioactive compounds with repellent, antifeed stored product insect pests have been reported however, their levels of control are still wanting. The major issue is that the oil yields obtained are low, unstable and high costs involved in production to use on a commercial scale. Use of these oils in combinations or in formulations with botanical actives as synergists or stabilizers, may make them economically viable insecticides. evaluating plant extracts (Black pepper seeds, Nutmeg seeds, coriander leaves and roots) as potential synergists in formulations with pyrethrins for possible use in protection of synergism experiments were carried out on synergists at ratio 1:1 (synergist: pyrethrins) Topical application of synergist/ formulation on completely Randomized Design layout controlled laboratory conditions of 27 ± 2 hours. Probit analysis was used pyrethrins and mais formulations of synergist: pyrethrins, coriander leaves extract (CLHE), Nutmeg seed extract (NMHE) and Black pepper seed methanol extract (BPSME) were statistically significant (P 12.02%) mortality followed by CLHE (46.67 ± 3.33%), BPSME (43.33 ± 6.67%). BPSME and NMHE co PBO, BPSHE and CLHE values were above 20. Plant extracts BPSHE and CLHE and PBO synergized th exposure duration with co additive in the formulation and only a synergist at 20,000ppm while NMHE was antagonistic to pyrethrins. correspond to pyrethrins formulations at lower concentrations c average percentage mortalities will not be different from that of higher concentrations and CLHE c for 72 h duration.
Asian Journal of Current Engineering and Maths, 2013
We apply the notion of Banach space operator ideals in nuclear spaces through topological vector ... more We apply the notion of Banach space operator ideals in nuclear spaces through topological vector spaces. The motivation for this study came from attempts to generalize the structure of nuclear spaces as a result of nuclear maps from functional analysis context. The compact closed structure associated with the category of relations results to nuclear ideals. Basic properties of Banach space operator ideals in relation to the structure of nuclear spaces will be demonstrated. We therefore establish a close correspondence between Banach space operator ideals and nuclear ideals through topological vector spaces. Mathematics Subject Classification: 46A03, 46A22, 46B50.
The present study describes a simple, selective, rapid and economical method for the determinatio... more The present study describes a simple, selective, rapid and economical method for the determination of iron (III) in its synthetic alloys using 3-hydroxy -3phenyl-1(2,4,6tribromophenyl) triazene as metallochromic indicator in the PH and temperature range of 2.5-3.0 and 20 − 600c respectively. The colour and shape of the synthesized indicator was light yellow shinning needles having melting point of 590c. It was crystallized from ethanol. The results of elemental study showed that, the values of C, H, N obtained experimentally agrees very well with those obtained theoretically. The colour at the end point changes from violet to light yellow using EDTA as a titrant. There is no interference in either determination from common metal and anion ions other than Pb(II), Cr(II), Mo(VI), Mn(II), U(vI), Cu(II), Cd(II), F−, PO4, C2O4, HPO4. Reproducible and accurate results are obtained for 5.59 -1.12mg of Iron with relative error less than ±1.79% and standard deviation not more than 0.10%. The...
African Journal of Environmental Science and Technology, 2016
The applications of various clayey minerals are related to their structural, physical and chemica... more The applications of various clayey minerals are related to their structural, physical and chemical characteristics. The physical and chemical properties of the clayey minerals dictate their utilization in the process industries and beneficiation required before usage. The study aimed at establishing the potentiality of clayey minerals from the study area, and the possibility of exploring and exploiting them in order to spur industrial development and promote economic self reliance of Kenya as a nation. The plasticity, particle size, surface area, chemical and mineralogy composition, morphological, thermal analysis and other physical properties were studied using various techniques. The clay samples composed of albite (5-16.7%), kaolinite (11.4-36.2%), microcline (15.2-35.3%), quartz (24.3-68.1%), hornblende (7.6% in samples from Ngamwa only), and other mineral impurities in small amounts. Ngamwa clayey materials consist of high impurities of chemical oxides such as TiO 2 , MnO, MgO and Fe 2 O 3. Generally, quartz and iron were the major impurities present in the samples from the concerned sites. The findings shows that clayey minerals from the study area can be exploited for commercial production of ceramic products after beneficiation using low cost and environmental friendly techniques in order to reduce the levels of iron, quartz, and other impurities to acceptable levels.
The Banach space operator ideals and nuclear maps have a large class of morphisms which behave as... more The Banach space operator ideals and nuclear maps have a large class of morphisms which behave as if they were part of a compact closed category, that is, they allow one to transfer variables between the domain and the codomain. We use the concept of nuclearity in functional analysis to establish application aspect of Banach space ideal properties in the transmission of image over wireless network based on the embedded system.
African Journal of Environmental Science and Technology, 2015
Clay samples from Tharaka-Nithi County in Kenya were characterized by hydrometer, X-ray fluoresce... more Clay samples from Tharaka-Nithi County in Kenya were characterized by hydrometer, X-ray fluorescence spectroscopy (XRF), atomic absorption spectroscopy (AAS), TGA, scanning electron microscopy (SEM) and powder diffraction (XRD) methods. The F-test and t-test were used to interpret the results. The major oxides present were Al2O3, SiO2 and the minor ones were CaO, TiO2, MnO, Fe2O3, K2O, MgO and Na2O. The values of SiO2 were greater than those of Al2O3, indicating that the samples were of clay minerals. The clay minerals with low cation exchange capacity (CEC) were present in the samples. The Atterberg limits showed that the inorganic clays of either low or intermediate plasticity having low contents of organic matter were present in the samples. The analysis further showed the availability of essential elements necessary for plant growth. The TGA analysis indicated that the decomposition of clay samples occurred in four steps. The scanning electron microscope photographs revealed tha...
Research Journal of Life Sciences, Bioinformatics, Pharmaceutical and Chemical Sciences, 2020
New metallochromic indicators belonging to the class of hydroxytriazenes has been evaluated for t... more New metallochromic indicators belonging to the class of hydroxytriazenes has been evaluated for the direct complexometric determination of Zinc in the presence of diverse ions. Reagent no (i), (ii) and (iii) has been found to be excellent indicators in the titration with EDTA at pH 6.95-7.50, 6.90-7.60 and 7.00-7.50 respectively. The colour at the end point was from light green to colourless and the titration was carried out between temperature range of 20-60C. Cl, Br,CH3COO , CO3 , SO4 , NO2 , SO3 , F, NO3 , I, S, WO4 , MO7O24 , NH4 , Na, K, U(VI), Mn(II), Ba(II), Hg(II), Sn(II), Cd(II), Mg(II), Ca (II), Zr(IV) can be tolerated in the titration of zinc (II) when they are present in equivalent amount with that of zinc (II). However, PO4 , Co (II), Cu (II) and Ni (II) interferes and when present in the environmental samples, separation techniques such as masking and demasking agents must be employed. The utility of the technique was checked by using 3-Hydroxy-3-m-toly-1-0-Carboxyphen...
Geophagy is the deliberate consumption of soil and clay deposits by animals, including man. Durin... more Geophagy is the deliberate consumption of soil and clay deposits by animals, including man. During pregnancy all the nourishment needed by the developing fetus comes from the mother, either the food she eats or the supplement she may take. The geochemical and mineralogical composition of the materials which are consumed by pregnant women from Meru, Embu and Chuka open air markets were studied. The geophagic materials were subjected to standard digestion procedures and analyzed for full assay and elemental analysis for Co, Zn, Mg, Cu, Pb and Cd using Atomic absorption spectrometry and Energy-dispersive x-ray fluorescence spectrometry in 30 geophagic samples. The mineralogical composition was investigated using X-ray diffractometry (XRD). The geochemical analysis revealed that the geophagic materials contain high levels of silica from 48.59 to 60.27%. Geophagic materials from Embu showed the highest concentration of Pb at 0.96 ppm. The levels of Pb in all samples exceeded the levels recommended by WHO/FAO limits of 0.01 ppm. The levels obtained for Cd in all the samples did not exceed the WHO/FAO limits of 0.003 ppm. The XRD data showed that the geophagic materials of the area consisted mainly of silica.
A simple, rapid and reasonable selective Complexometric technique for nickel (II) determination u... more A simple, rapid and reasonable selective Complexometric technique for nickel (II) determination using some selected hydroxytriazene as a metallochromic indicator is reported in the present study. The colour change at the end point was from greenish-yellow/yellow to colourless with sharp end point. The pH ranges were 9.3-9.7, 9.0-9.5, 8.5-9.0, 8.0-8.5 while temperature ranges were 25-60, 25-60, 25-60, 25-50 and 25-50 0C for reagent (i), (ii), (iii), (iv), and (v) respectively. Nickel(II) was determined accurately up to concentration as low as 3.0x10-3M for reagents (ii), (iv), and (v)) while for reagents (i) and (iii) the concentration range could be even lowered to 1.0x10-3M for the determination of nickel (II). The ions such as Cl-, Br-, CH3COO, CO3, PO4, SO4, C2O4, S2O3, NO2-, SO3, S2-, HPO4, F-, NO3, WO4, MO7O24, I-, NH4, Na+, K+ did not show any interference in the determination of nickel (II) even when they were present in tenfold excess. Ba2+, Mg2+, Ca2+, were tolerated up to ...
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