P137 DEGRADATION RESISTANCE OF PVDF MESH IN VIVO IN COMPARISON TO PP MESH

Aim To researched the degradation resistance of PVDF mesh by comparing its morphological and chemical condition with PP mesh. Material and Methods PVDF and PP meshes analysed in this study were received from a previous animal experiment. To expose the surface of explanted meshes, a tissue removing method with protease was used and the result of this cleaning process was tested by X-ray Photoelectron Spectroscopy (XPS). The morphological condition of the mesh surface was compared using Scanning Electron Microscopy (SEM) and the chemical condition concerning degradation was analysed through Fourier Transform Infrared Spectroscopy (FTIR). The surface condition of PVDF mesh after 3-, 6-, 12- and 24-month implantation was illustrated and compared with two types of PP meshes. Results XPS revealed an absence of nitrogen, confirming the successful removal of tissue residues using protease. SEM results presented no notable morphological surface change of the PVDF mesh and progressive surface cracking processes over time of both types of PP meshes. FTIR spectra of the implanted PVDF meshes had no considerable difference from the spectrum of the pristine mesh, while FTIR spectra of both types of PP meshes had extra chemical functional groups increasing with implantation time, indicating progressive degradation. Conclusions PVDF mesh does not show signs of degradation up to 24 months after implantation while PP meshes progressively degrade with increasing time under the same conditions, which appears as worsening Environmental Stress Cracks. This study highlights the morphological and chemical stability of the PVDF mesh and demonstrates that the PVDF mesh is more resistant to degradation in comparison to the PP meshes.

Ekosistem Mangrove Binuangeun, Banten: Kondisi Fisik Dan Kimia Serta Ragam Ikan

Binuangeun Mangrove Ecosystem is located in the south western Java Island, in the area of ​​Lebak Regency, Banten Province. Mangrove ecosystems are ecosystems that located at the Coastal areas which are a habitat for a variety of marine animals which are associated with it, mostly fish, because of its complex or a very effective root structure which can provide a place for fish to be able to live, take shelter, develop, breed and also look for food. This research was conducted to determine the physical and chemical condition and the variety of fishes which found in the Binuangeu, Banten Mangrove Ecosystem. This research method uses literature study. Physical and chemical conditions of the Binuangeun Mangrove Ecosystem, Banten have degrees of temperature ranging from 28.20 - 32.20; acidity range between 7.00 - 8.09; turbidity ranges from 22.50 - 76.00 NTU; water current ranged from 0.079 to 0.189; phosphate content ranges from 0.02 - 0.008; salinity ranges from 30-35 PSU; and dissolved oxygen content ranges from 5.67 - 8.70. The types of fish found in the Binuangeun Mangrove Ecosystem, Banten are 45 species from 22 Family. The most abundant and relatively high species of existence is the Gobiidae with 10 species. Keywords: Banten, Binuangeun, Ecosystems, Fish, Mangroves

Seasonal changes in the abundance of benthic macroinvertebrates & physico-chemical condition of Moussa Stream Bida, Nigeria

Seasonal changes in the abundance of benthic macroinvertebrates and physico-chemical condition of Moussa Stream, Bida Nigeria, were studied monthly from January to August 2017. Macroinvertebrates were sampled using modified kick sampling techniques. Three different sampling stations were selected along the course of the Stream. The results from the stream showed that water temperature (24.9-27.50C), Depth (14.7-45.8cm), Flow velocity (0.14-0.23m/s), Biochemical oxygen demand (2.0-7.0mg/L), pH (6.33-8.6), Conductivity (20-63μ/cm), Alkalinity (8-30mg/L), Turbidity (61-285NTU), Nitrate (0.87-3.85mg/L) and Phosphate (0.31-1.01mg/L) were within the maximum permissible limit (WHO, SON) except Dissolved oxygen (3.1-10mg/L). Most of the parameters investigated with the exception of depth and flow velocity showed no significant difference (p>0.05) among all the sampling stations. Temperature, depth and flow velocity showed no significant differences with season. pH, DO, BOD5, Turbidity, Conductivity, Alkalinity, Nitrate, and Phosphate were significantly higher during wet season. A total of 471 individuals from 30 species and 20 families of invertebrates were recorded. The overall macroinvertebrates recorded from station 1, 2 and 3 were 166(35.24%), 149(31.63%) and 156(33.12%). Overall, there was significant difference (P<0.05) in number of individuals among the sampling stations. The abundance according to the Orders revealed that Coleopterans, Odonata and Hemipterans were the most common groups encountered. Ephemeroptera Diptera, Mollusca and Oligochaeta were sparingly found in all stations. The percentage and total number of individuals of macroinvertebrates recorded during the study period shows 67.09% (316 individuals) in dry season and the remaining 32.90% (155 individuals) were recorded in rainy season. CCA result correlated positively between species abundances and measured environmental variables. Low density of pollution sensitive macro invertebrates groups and the deteriorating water quality were implications of pollution stress caused by anthropogenic activities. Key words: seasonal changes, macroinvertebrates, stream, Bida.

Simulation of droplet ejection based on electromechanical parameters & chemical condition for controlling inkjet printing devices

In this study, the droplets in inkjet printing have been simulated based on mechanical parameters including temperature and pressure changing and also the chemical condition contain dielectric of various solvent materials has been investigated. Basically in viewpoint of electromechanical parameters we simulated and divided the inkjet printing into the piezoelectric type and thermal type, and as our results shows, each type has advantages and disadvantages. In this paper the piezoelectric types which has features such as; ink delivery quantity, driving control, controlling of droplet size based on color representation, generating heat and superb reliability have been introduced. By this work, we exhibit the deformation of piezoelectric elements is applied in two ways, consist of thickness deformation and sliding deformation. This chamber is included in a small slot that is created through two piezoelectric crystal plates .In addition the voltages inserted to the piezoelectric walls on both sides cause deformation mode. Due to this operation shear mode deformation occurs to both walls and via the ink pressure chamber, ink drops are delivered. Several inks applied as a dielectric material layers for conductive track in electrochemical sensors. Thus, passivation of printed sensors and deposition of adhesives can be achieved simultaneously. In this work, the presented method for the printing of UV-curable adhesive and dielectric inks demonstrates a rapid facile prototyping process.