Cell Wall Morphology, Chemical and Thermal Analysis of Cultivated Pineapple Leaf Fibres for Industrial Applications

A study on chemical, morphology, and thermal analysis of cultivated pineapple leaf fibres (PALF) were carried out. The chemical compositions were determined by using Technical Association Pulp and Paper Industries standards. Fourier Transform-Infrared Spectroscopy analysis of PALF detect sharp band at 1,733?cm^?1, due to the absorption of carbonyl stretching of ester and carboxyl groups which is most abundant in pineapple leaf hemicelluloses. Cell wall ultra structure of PALF was studied by using Transmission electron microscopy. Transmission electron micrograph confirmed that cell wall structure of PALF consists of middle lamella, primary wall and secondary wall including S₁, S₂ and S₃ layers. X-Ray Diffraction indicated that PALF have crystalline nature. Thermal analysis of PALF shows that T_10% and T_50% weight loss occurred at temperature of 212 and 306?°C respectively. Differential Scanning Calorimetry of PALF showed the broad endothermic peak at a temperature of 80?°C. The relationships between these properties were discussed and relate it with industrial application of pineapple leaf fibers.     

Observed trends for CF3-containing compounds in background air at Cape Meares, Oregon, Point Barrow, Alaska, and Palmer Station, Antarctica

The concentrations of CF(3)-containing compounds in archived air samples collected at Cape Meares, Oregon, from 1978 to 1997, at Point Barrow, Alaska, from 1995 to 1998, and at Palmer Station, Antarctica, from 1991 to 1997, were determined by high resolution gas chromatography and high resolution mass spectrometry. The CF(3)-containing compounds measured by this method and discussed here are: the perfluorinated compound, C(3)F(8) (FC 218); four perhalogenated compounds, CF(3)Cl (CFC 13), CF(3)CF(2)Cl (CFC 115), CF(3)CFCl(2) (CFC 114a), and CF(3)Br (Halon 1301); and three hydrofluorocompounds, CF(3)H (HFC 23), CF(3)CH(3) (HFC 143a), and CF(3)CH(2)F (HFC 134a). For four of these compounds, very few measurements have been previously reported. The atmospheric concentrations of all of the CF(3)-containing compounds continuously increased in time over the sample collection periods. From these data, the annual rates of emission into the atmosphere have been estimated. The emission rates fall into one of three distinct categories. The annual emission rates of C(3)F(8), CF(3)H, CF(3)CH(3), and CF(3)CH(2)F have continuously increased over the last two decades. That of CF(3)CFCl(2) has decreased continuously. Emission rates for CF(3)Cl, CF(3)CF(2)Cl, and CF(3)Br reached maximum levels in the late 1980s, and have been decreasing in the 1990s. The emission rates of C(3)F(8), CF(3)CH(3) and CF(3)CH(2)F were nearly zero 20 years ago but have increased rapidly during the last decade.     

Fate of glutaraldehyde in hospital wastewater and combined effects of glutaraldehyde and surfactants on aquatic organisms

Glutaraldehyde (GA), an aliphatic dialdehyde disinfectant, and surfactants, one of the major components of detergents, are widely used in hospitals in order to eliminate pathogenic organisms causing nosocomial infectious diseases. After their use, disinfectants and surfactants reach the wastewater network together. The discharge of chemical compounds from hospital activities into wastewater is also a well-known problem, causing pollution of water resources and constituting an ecological risk for aquatic organisms. In this study, the chemistry and toxicology of GA and surfactant mixtures were reviewed in order to estimate their fate in aquatic ecosystems. Furthermore, their joint effects on aquatic organisms were experimentally assessed in the laboratory. A simple model of the additive joint action of toxicants was used to determine combined acute toxicity effects on the bacteria luminescence and Daphnia mobility of three mixtures containing GA at 1.5 x EC50 24 h [in mg/L] on Daphnia and anionic, cationic and nonionic surfactants at twice their critical micellar concentration (CMC). The mixture of GA and a cationic surfactant gave an EC50 30 min on Vibrio fischeri of 0.158%, with a concentration of 0.04 mg GA/L and 1.04 mg CTAB/L, which provided an additive action. The interaction between GA and an anionic surfactant on V. fischeri produced an antagonistic joint action with an EC50 30 min of 3.95%, containing 1.06 mg GA/L and 33.2 mg SDS/L. A synergistic action with an EC50 30 min of 8.4% on V. fischeri was observed for the mixture containing GA and a nonionic surfactant. Antagonistic interactions were observed for the joint action between GA and the surfactants studied on Daphnia. The mixture of GA and CTAB was more toxic (EC50 24 h=0.02%) than the two other mixtures (EC50 24 h GA+SDS=6%; EC50 24 h GA+TX 100=10%). This study provides new data on the toxicity of certain hospital pollutants entering the aquatic environment and detected in surface and groundwaters. It is necessary to study the joint effects of GA and surfactant mixtures following chronic and sublethal standard bioassays in order to estimate the contribution of the additive joint action models in assessing the environmental risk of hospital wastewater (HW).     

Climate simulations using the GCRC 2-D zonally averaged statistical dynamical climate model

The two-dimensional statistical dynamical climate model, recently developed at the Global Change Research Center (GCRC 2D climate model) is presented and discussed. The model solves the 2-D primitive equations in finite difference form (mass continuity, Newton's second law, and the first law of thermodynamics) for the prognostic variables zonal mean density, zonal mean zonal velocity, zonal mean meridional velocity, and zonal mean temperature on a grid that has 18 nodes in latitude and 9 vertical nodes (plus the surface). The equation of state, p = ρRT and an assumed hydrostatic atmosphere, δp = −ρgδz, are used to diagnostically calculate the zonal mean pressure and vertical velocity for each grid node, and the moisture balance equation is used to estimate the precipitation rate.

The performance of the model at simulating the two-dimensional temperature, zonal winds, and mass stream function is discussed here. The strengths and weaknesses of the model are highlighted and plans for future model experiments and improvements are given. The parameterization of the transient eddy fluxes of heat and momentum developed by Stone and Yao (1987 and 1990) are used with small modifications. These modifications are shown to improve the performance of the model at simulating the observed climate system as well as increase the model's computational stability.     

Synthesis and Characterization of Novel Biobased Ion-Exchange Bisfuran Polyamides Prepared by Interfacial Polycondensation of Bisfuran Diamine Monomer and Sustainable Dicarboxylic Acid Derivatives

Journal of Polymers and the Environment - Polymers based on the furanic compounds derived from renewable carbohydrates have seen massive growth due to their unique properties and increasing...     

Removal of polycyclic aromatic hydrocarbons from aged-contaminated soil using cyclodextrins: experimental study

The removal of polycyclic aromatic hydrocarbons (PAHs) from soil using water as flushing agent is relatively ineffective due to their low aqueous solubility. However, addition of cyclodextrin (CD) in washing solutions has been shown to increase the removal efficiency several times. Herein are investigated the effectiveness of cyclodextrin to remove PAH occurring in industrially aged-contaminated soil. Beta-cyclodextrin (BCD), hydroxypropyl-beta-cyclodextrin (HPCD) and methyl-beta-cyclodextrin (MCD) solutions were used for soil flushing in column test to evaluate some influent parameters that can significantly increase the removal efficiency. The process parameters chosen were CD concentration, ratio of washing solution volume to soil weight, and temperature of washing solution. These parameters were found to have a significant and almost linear effect on PAH removal from the contaminated soil, except the temperature where no significant enhancement in PAH extraction was observed for temperature range from 5 to 35 degrees C. The PAHs extraction enhancement factor compared to water was about 200.     

Correction to: Reducing ammonia emission by aluminum sulfate addition in litter and its influence on productive,reproductive, and physiological parameters of dual-purpose breeding hens

Environmental Science and Pollution Research -     

Investigating feasible sites for multi-purpose small dams in Swat District of Khyber Pakhtunkhwa Province,Pakistan: socioeconomic and environmental considerations

Environment, Development and Sustainability - The low water storage capacity caused water crisis in Pakistan; therefore, the country needs both small- and large-scale reservoirs to store surplus...