Abstract: This study was conducted to determine the physicochemical characteristics and heavy metal concentration (Cadmium (Cd), Copper (Cu), Iron (Fe), Lead (Pb) and Zinc (Zn)) in freshwater from Jega river. 30 water samples were collected in two 1-liter sterile plastic containers from three designated sampling points, namely; Station A (before the bridge; upstream), Station B (at the bridge where human activities such as washing of cars, motorbike, clothes, bathing and other household materials are concentrated), Station C (after the bridge; downstream) fortnightly, between March and July 2014. Results indicated that the highest pH mean value of 7.08 ± 1.12 was observed in station C, the highest conductivity with the mean 58.75 ± 7.87 µs/cm was observed at station A, the highest mean value of the water total hardness was observed at station A (54 ± 16.11 mg/L), the highest mean value of nitrate deposit was observed in station A (1.66 ± 1.33 mg/L), the highest mean value of alkalinity was observed at station B (51.33 ± 6.66 mg/L) and the highest mean (39.56 ± 3.24 mg/L) of total dissolved solids was observed at station A. The highest concentration mean value of Fe was observed in station C (65.33 ± 4.50 mg/L), the highest concentrations of Cd was observed in station C (0.99 ± 0.36 mg/L), the mean value of 2.13 ± 1.99 mg/L was the highest concentration of Zn observed in station B, the concentration of Pb was not detected (ND) and the highest concentration of Cu with the mean value of 0.43 ± 0.16 mg/L was observed in station B, while the lowest concentration was observed at station C (0.27 ± 0.26 mg/L). Statistical analysis shows no significant difference (P > 0.05) among the sampling stations for both the physicochemical characteristics and heavy metal concentrations. The results were found to be within the internationally acceptable standard limits.
Abstract: Substituting natural aggregate with recycled aggregate coming from concrete demolition represents a promising alternative to face the issues of both the depletion of natural resources and the congestion of waste storage facilities. However, the crushing process of concrete demolition waste, currently in use to produce recycled concrete aggregate, does not allow the complete separation of natural aggregate from a variable amount of adhered mortar. Given the physicochemical characteristics of the latter, the introduction of recycled concrete aggregate into a concrete mix modifies, to a certain extent, both fresh and hardened concrete properties. As a consequence, the behavior of recycled reinforced concrete members could likely be influenced by the specificities of recycled concrete aggregates. Beyond the mechanical properties of concrete, and as a result of the composite character of reinforced concrete, the bond characteristics at the rebar/concrete interface have to be taken into account in an attempt to describe accurately the mechanical response of recycled reinforced concrete members. Hence, a comparative experimental campaign, including 16 pull-out tests, was carried out. Four concrete mixes with different recycled concrete aggregate content were tested. The main mechanical properties (compressive strength, tensile strength, Young’s modulus) of each concrete mix were measured through standard procedures. A single 14-mm-diameter ribbed rebar, representative of the diameters commonly used in the domain of civil engineering, was embedded into a 200-mm-side concrete cube. The resulting concrete cover is intended to ensure a pull-out type failure (i.e. exceedance of the rebar/concrete interface shear strength). A pull-out test carried out on the 100% recycled concrete specimen was enriched with exploratory acoustic emission measurements. Acoustic event location was performed by means of eight piezoelectric transducers distributed over the whole surface of the specimen. The resulting map was compared to existing data related to natural aggregate concrete. Damage distribution around the reinforcement and main features of the characteristic bond stress/free-end slip curve appeared to be similar to previous results obtained through comparable studies carried out on natural aggregate concrete. This seems to show that the usual bond mechanism sequence (‘chemical adhesion’, mechanical interlocking and friction) remains unchanged despite the addition of recycled concrete aggregate. However, the results also suggest that bond efficiency seems somewhat improved through the use of recycled concrete aggregate. This observation appears to be counter-intuitive with regard to the diminution of the main concrete mechanical properties with the recycled concrete aggregate content. As a consequence, the impact of recycled concrete aggregate content on bond characteristics seemingly represents an important factor which should be taken into account and likely to be further explored in order to determine flexural parameters such as deflection or crack distribution.
Abstract: Cassava peels and bamboo waste materials discarded from construction are two sources of waste that could constitute serious menace where they exist in large quantities and inadequately handled. The study examined the physicochemical characteristics of activated carbon materials derived from cassava peels and bamboo waste materials discarded from construction site. Both materials were subjected to carbonization and chemical activation using zinc chloride. Results show that the chemical activation of the materials had a more effect on pore formation in cassava peels than in bamboo materials. Bamboo material exhibited a reverse trend for zinc and sulphate ion decontamination efficiencies as the value of zinc chloride impregnation varied unlike cassava peel carbon biomass which exhibited a more consistent result of decontamination efficiency for the seven contaminants tested. Although waste bamboo biomass exhibited higher adsorption intensity as indicated by values of decontamination for most of the contaminants tested, the cassava peel carbon biomass showed a more balanced adsorption level.
Abstract: The present study presents, firstly, to characterize the physicochemical quality of brackish groundwater of the Terminal Complex (TC) from the region of Eloued-souf and to investigate the presence of fluoride, and secondly, to study the comparison of adsorbing power of three materials, such as (activated alumina AA, sodium clay SC and hydroxyapatite HAP) against the groundwater in the region of Eloued-souf. To do this, a sampling campaign over 16 wells and consumer taps was undertaken. The results show that the groundwater can be characterized by very high fluoride content and excessive mineralization that require in some cases, specific treatment before supply. The study of adsorption revealed removal efficiencies fluoride by three adsorbents, maximum adsorption is achieved after 45 minutes at 90%, 83.4% and 73.95%, and with an adsorbed fluoride content of 0.22 mg/L, 0.318 mg/L and 0.52 mg/L for AA, HAP and SC, respectively. The acidity of the medium significantly affects the removal fluoride. Results deducted from the adsorption isotherms also showed that the retention follows the Langmuir model. The adsorption tests by adsorbent materials show that the physicochemical characteristics of brackish water are changed after treatment. The adsorption mechanism is an exchange between the OH- ions and fluoride ions. Three materials are proving to be effective adsorbents for fluoride removal that could be developed into a viable technology to help reduce the salinity of the Saharan hyper-fluorinated waters. Finally, a comparison between the results obtained from the different adsorbents allowed us to conclude that the defluoridation by AA is the process of choice for many waters of the region of Eloued-souf, because it was shown to be a very interesting and promising technique.
Abstract: The chemical and physical characteristics of rainwater
harvested from a typical rooftop were progressively studied. The
samples of rainwater collected were analyzed for pH, major ion
concentrations, TDS, turbidity, conductivity. All the Physicochemical
constituents fell within the WHO guideline limits at some points as
rainfall progresses except the pH. All the components of rainwater
quality measured during the study showed higher concentrations
during the early stages of rainfall and reduce as time progresses.
There was a downward trend in terms of pH as rain progressed, with
18% of the samples recording pH below the WHO limit of 6.5-8.0. It
was observed that iron concentration was above the WHO threshold
value of 0.3 mg/l on occasions of heavy rains. The results revealed
that most of physicochemical characteristics of rainwater samples
were generally below the WHO threshold, as such, the rainwater
characteristics showed satisfactory conditions in terms of
physicochemical constituents.
Abstract: Complexation of anthocyanins to mimic natural
copigmentation process was investigated. Cyanidin-rich extracts from
Zea mays L. ceritina Kulesh. and delphinidin-rich extracts from
Clitoria ternatea L. were used to form 4 anthocyanin complexes,
AC1, AC2, AC3 and AC4, in the presence of several polyphenols and
a trace metal. Characterizations of the ACs were conducted by UV,
FTIR, DSC/TGA and morphological observations. Bathochromic
shifts of the UV spectra of 4 formulas of ACs were observed at peak
wavelengths of about 510-620 nm by 10 nm suggesting complex
formation. FTIR spectra of the ACs indicate shifts of peaks from
1,733 cm-1 to 1,696 cm-1 indicating interactions and a decrease in the
peak areas within the wavenumber of 3,400-3,500 cm-1 indicating
changes in hydrogen bonding. Thermal analysis of all of the ACs
suggests increases in melting temperature after complexation. AC
with the highest melting temperature was morphologically observed
by SEM and TEM to be crystal-like particles within a range of 50 to
200 nm. Particle size analysis of the AC by laser diffraction gave a
range of 50-600 nm, indicating aggregation. This AC was shown to
have no cytotoxic effect on cultured HGEPp0.5 and HGF (all p>
0.05) by MTT. Therefore, complexation of anthocyanins was simple
and self-assembly process, potentially resulting in nanosized particles
of anthocyanin complex.
Abstract: Anthocyanins are natural pigments with effective UV
protection but their topical use could be limited due to their
physicochemical characteristics. An attempt to overcome such
limitations by complexation of 2 major anthocyanin-rich sources, C.
ternatea and Z. mays, has potentiated its use as topical antiinflammatory.
Cell studies indicate no cytotoxicity of the
anthocyanin complex (AC) up to 1 mg/ml tested in HaCaT and
human fore head fibroblasts by MTT. Croton oil-induced ear edema
in Wistar rats suggests an effective dose of 5 mg/cm2 of AC as a
topical anti-inflammatory in comparison to 0.5 mg/cm2 of
fluocinolone acetonide. Niosomal encapsulation of the AC
significantly prolonged the anti-inflammatory activity particularly at
8 h after topical application (p = 0.0001). The AC was not cytotoxic
and its anti-inflammatory and activity was dose-dependent and
prolonged by niosomal encapsulation. It has also shown to promote
collagen type 1 production in cell culture. Thus, AC could be a
potential candidate for topical anti-inflammatory agent from natural
resources.
Abstract: The aim of the present study is to investigate the
potential use of the selected seed oils. The oil was extracted using
Soxhlet apparatus and the physicochemical characteristics of the oil
determined using standard methods. The following results were
obtained for the physicochemical parameters analysed: for Egusi seed
oil, Oil yield 53.20%, Saponification value 178.03±1.25 mgKOH/g,
Iodine value 49.10±0.32 g I2/100g, Acid value 4.30±0.86 mgKOH/g,
and Peroxide value 5.80±0.27 meq/kg were obtained. For Pawpaw
seed oil, Oil yield 40.10%, Saponification value 24.13±3.93
mgKOH/g, Iodine value 24.87±0.19 g I2/100g, Acid value 9.46±0.40
mgKOH/g, and Peroxide value 3.12±1.22 meq/kg were obtained. For
Sweet orange seed oil, Oil yield 43.10%, Saponification value
106.30±2.37 mgKOH/g, Iodine value 37.08±0.04 g I2/100g, Acid
value 7.59±0.77 mgKOH/g, and Peroxide value 2.21±0.46 meq/kg
were obtained. From the obtained values of the determined
parameters, the oils can be extracted from the three selected seeds in
commercial quantities and that the egusi and sweet orange seed oils
may be utilized in the industrial soap production.
Abstract: Raisin Concentrate (RC) are the most important
products obtained in the raisin processing industries. These RC
products are now used to make the syrups, drinks and confectionery
productions and introduced as natural substitute for sugar in food
applications. Iran is a one of the biggest raisin exporter in the world
but unfortunately despite a good raw material, no serious effort to
extract the RC has been taken in Iran. Therefore, in this paper, we
determined and analyzed affected parameters on extracting RC
process and then optimizing these parameters for design the
extracting RC process in two types of raisin (round and long)
produced in Khorasan region. Two levels of solvent (1:1 and 2:1),
three levels of extraction temperature (60°C, 70°C and 80°C), and
three levels of concentration temperature (50°C, 60°C and 70°C)
were the treatments. Finally physicochemical characteristics of the
obtained concentrate such as color, viscosity, percentage of reduction
sugar, acidity and the microbial tests (mould and yeast) were
counted. The analysis was performed on the basis of factorial in the
form of completely randomized design (CRD) and Duncan's multiple
range test (DMRT) was used for the comparison of the means.
Statistical analysis of results showed that optimal conditions for
production of concentrate is round raisins when the solvent ratio was
2:1 with extraction temperature of 60°C and then concentration
temperature of 50°C. Round raisin is cheaper than the long one, and
it is more economical to concentrate production. Furthermore, round
raisin has more aromas and the less color degree with increasing the
temperature of concentration and extraction. Finally, according to
mentioned factors the concentrate of round raisin is recommended.
Abstract: New design of a grid for preparation of high density
granules with enhanced mechanical strength by granulation of
dispersed materials is suggested.
A method for hydrodynamic dimensioning of the grid depending
on granulation conditions, hydrodynamic regime of the operation,
dispersity and physicochemical characteristics of the materials to be
granulated was suggested.
The aim of the grid design is to solve the problems arising by the
granulation of disperse materials.
Abstract: We aimed to investigate how can target and optimize
pulmonary delivery distribution by changing physicochemical
characteristics of instilled liquid.Therefore, we created a new liquids
group:
a. eligible for desired distribution within lung because of
assorted physicochemical characteristics
b. capable of being augmented with a broad range of
chemicals inertly
c. no interference on respiratory function
d. compatible with airway surface liquid
We developed forty types of new liquid,were composed of
Carboxymethylcellulose sodium,Glycerin and different types of
Polysorbates.Viscosity was measured using a Programmable
Rheometer and surface tension by KRUSS Tensiometer.We
subsequently examined the liquids and delivery protocols by simple
and branched glass capillary tube models of airways.Eventually,we
explored pulmonary distribution of liquids being augmented with
technetium-99m in mechanically ventilated rabbits.We used a single
head large field of view gamma camera.Kinematic viscosity between
0.265Stokes and 0.289Stokes,density between 1g/cm3 and 1.5g/cm3
and surface tension between 25dyn/cm and 35dyn/cm were the most
acceptable.