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This study aims to evaluate the effect of Piper betle leaf extract towards the acute-lethal toxicity, LC50 of red Nile tilapia juveniles (Oreochromis niloticus).

Ten red Nile tilapia juveniles per tank (in triplicate) were used as an experimental fish for the LC50 bioassay. Five different concentrations of P. betle extract; 80 ppm, 90 ppm, 100 ppm, 110 ppm and 120 ppm, were tested on the red Nile tilapia juveniles and one tank was acting as a control. The progress of the LC50 and lethal time of fish mortality were observed and recorded within the random interval of 96 h. The value for LC50 was determined as 100 ppm of P. betle leaf extract. Higher number of fish mortalities was observed when concentration higher than 100 ppm was tested on to the red Nile tilapia juveniles.

Data obtained shows that the P. betle concentration of 120 ppm accelerated the fish mortality period.

However, adaption of P. betle extract occurred after 50 h, as there was no fish mortality observed within the time.

The purpose of this paper is to evaluate the antioxidant activity and toxicity of Clinacanthus nutans leaves from three conventional extraction methods, i.e. maceration, Soxhlet and magnetic stirring.

Total flavonoid content (TFC) and phenolic content (TPC) were determined using colorimetric method of aluminum chloride and Folin-Ciocalteu (FC) assay, respectively. Antioxidant property of C. nutans was evaluated using 2,2'-diphenyl-1-pierylhydrazyl (DPPH) free radical scavenging assay. Cytotoxic activity of C. nutans against brine shrimp was evaluated based on LC50 (lethality concentration) after 24 h exposure to the plant extract.

The highest TPC of C. nutans was observed with Soxhlet extraction method (98.87 ± 10.43 mg of gallic acid equivalents (GAE/g) followed by maceration (68.77 ± 2.45 mg of GAE/g) and magnetic stirring (46.75 ± 2.45 mg of GAE/g). Interestingly, remarkable highest TFC was observed with magnetic stirring (568.90 ± 4.85 mg of rutin equivalent (RE)/g) followed by maceration (249.60 ± 2.79 mg of RE/g) and Soxhlet (174.8 ± 1.74 mg of RE/g). On the other hands, the extract obtained using maceration method showed the highest antioxidant activity (IC50: 14.18 mg/mL compared to ascorbic acid 144.36 µg/mL). Cytotoxicity of C. nutans from all extraction methods showed similar LC50 values with maceration (3.81 mg/mL), Soxhlet (2.61 mg/mL) and magnetic stirring (4.56 mg/mL), respectively.

Both phenolic and flavonoids are responsible for the antioxidant activity, of C. nutans extracts. Based on Meyer's toxicity index, all extracts were nontoxic (LC50>1 mg/mL).

The purpose of this paper is to predict the aquatic toxicity (LC50) of 92 substituted benzenes derivatives in Pimephales promelas.

Quantitative structure-activity relationship analysis was performed on a series of 92 substituted benzenes derivatives using multiple linear regression (MLR), artificial neural network (ANN) and support vector machines (SVM) methods, which correlate aquatic toxicity (LC50) values of these chemicals to their structural descriptors. At first, the entire data set was split according to Kennard and Stone algorithm into a training set (74 chemicals) and a test set (18 chemical) for statistical external validation.

Models with six descriptors were developed using as independent variables theoretical descriptors derived from Dragon software when applying genetic algorithm – variable subset selection procedure.

The values of Q2 and RMSE in internal validation for MLR, SVM, and ANN model were: (0.8829; 0.225), (0.8882; 0.222); (0.8980; 0.214), respectively and also for external validation were: (0.9538; 0.141); (0.947; 0.146); (0.9564; 0.146). The statistical parameters obtained for the three approaches are very similar, which confirm that our six parameters model is stable, robust and significant.

Paper aims to Preparation and evaluation of isoxazole benzene sulfonamide derivatives and incorporated it with waterborne household paints to develop coating compositions as an insecticidal coating against Musca domestica adults.

The synthesized compounds were prepared and confirmed by different analyzes, fourier transform infra-red (FTIR), mass, proton nuclear magnetic resonance (¹HNMR) and Carbon 13 nuclear magnetic resonance (¹³CNMR) spectra. The prepared compound has been blended with waterborne household paint formulation, the physical and mechanical properties of the paint formulation has been studied. The efficiency of the isoxazole benzene sulfonamide derivatives when incorporated with waterborne paint against Culex quinquefasciatus and Mosquito house fly adults, also have been examined.

The obtained results of the paint formulations confirmed their best performance and providing good scrub resistance. Also, the finding promising results of the insecticide test of the paint formulation may be because of the biological activity of these compounds and containing sulfonamide, cyanide and free aromatic amine groups comparing with the standard recommended organophosphorus insecticide. The order activity increase with increasing the dose concentration of the isoxazole derivatives and the activity of chemical compounds itself is represented in terms of their medium lethal concentrations LC50 (LC90), which recorded 0.90(1.62), 0.89(1.61) and 0.86(1.56) g/ml for 5, 3 and 4 chemical compounds, respectively, after 72 h from treatment.

These types of organic compounds are friendly environmentally and can be used as a biocide with different types of paint formulations.

Insecticide waterborne household paints based on isoxazole benzene sulfonamide derivatives as insecticide agents are novel.

Moringa oleifera (MO) is a herbal remedy that is rich in essential amino acids and phytochemicals in the leaves, seeds and pods. It is becoming a famous food in various ethnic groups, and the consumption is increasing worldwide. However, there is no safety profile of the hydroalcoholic MO leaf extracts, or documented teratogenicity aspect. This study was sought to compare the antioxidant activity and the teratogenicity of hydroalcoholic MO leaf extracts in the zebrafish embryo.

MO leaves were extracted with aqueous alcohols (ethanol or methanol: water, 80:20 v/v) using the Soxhlet method. The antioxidant capacity was determined using DPPH assay. The concentrations of extracts ranging from 3 to 1,000 µg/mL were used to examine the toxicity and teratogenicity on the zebrafish embryo.

Both hydroalcoholic MO leaf extracts were positive for alkaloids, terpenoids, steroids, tannins, flavonoids, phenols, coumarins, quinones and glycosides, except saponins only absent in aqueous methanol extract. The antioxidant capacity based on lC₅₀, was 15.92 ± 3.62 mg/mL for aqueous methanolic and 25.28 ± 2.89 mg/mL for aqueous ethanolic extract. For acute toxicity, the aqueous methanolic extract has lower LC₅₀ (163.87 ± 12.88 µg/mL) compared to aqueous ethanolic extract (337.48 ± 30.04 µg/mL). The embryo treated with aqueous methanolic extract showed phenotypic defect but not on the aqueous ethanolic extract.

This study suggests that aqueous methanol of MO leaves extract has better antioxidant capacity compared to ethanol, and ethanolic leaf extract is safer (higher LC50 and no teratogenicity) than methanolic extract.

The purpose of this study is assessment of fire and smoke hazards of some fiber reinforced polymers (FRP). The use of FRP strengthening strips has been found rapid growth in construction industry of Iran and many other countries. However, the fire and smoke hazards of these materials in both construction and use phases need to be determined and the appropriated measures against fire should be taken.

The fire hazards of two types of fibre-reinforced epoxy composites (graphite fibre-reinforced polymer and carbon fibre-reinforced polymer) were investigated in bench-scale using cone calorimeter test method. Time to ignition, heat release rate, total heat release, smoke release and carbon monoxide production were measured and analysed. Time to flashover of an assumed room lined with the tested FRP was analysed with Conetools software. Smoke production and toxicity of the considered composites were also analysed and discussed, using the fractional effective dose parameter.

The results showed that the tested FRP products had a high fire hazard and a potential high contribution to fire growth. The tests also proved that the used epoxy resin had a low glass transition temperature, around 50°C; therefore, the mechanical strength of the product could be drastically reduced at first stages of a probable fire incident. This also showed that a regular thermal barrier, typically used for protection of plastic foams against fire, could not be sufficient for the protection of strengthening FRP composites.

This research was carried out for the first time for the materials used in construction industry of Iran. The results and achievements were very useful for safe use and development of proper details of application of the system.

This paper discusses the development and implementation of Chemical Exchange Directory (CED), an online advertising service for the chemical industry. One of the major problems in the chemical market is the identification of viable suppliers for products in a rapidly expanding market with large numbers of products, each with many different potential applications. CED has been designed by chemical industry personnel to be used by people with little data processing training; there are no complex search languages and procedures. Data input and output are facilitated by using a simple datasheet format to define each product. Information providers supply and modify product information online. Uniform transaction pricing has been adopted to follow industry control procedures. The service is the forerunner of other online business applications in the chemical industry.

Hiding in one‐coat at a coverage rate of 19m2/litre, easy application, and long‐term protection are principal advatages of a new high‐gloss lead and chromate‐free Labour Saver coating, High‐performance Alkyd System 2000, developed by Rust‐Oleum International,Roosendaal, the Netherlands. A solids content of 75—81% by volume gives the high‐performance coating its economical coverage rate of 19m2/litre, almost 50% greater than conventional alkyd topcats, at the recommended dry‐film thickness of 40 microns. It has exellent flow and wet edge characteristics when appied by brush or roller and can also be applied by airless or air‐atomised spray. Hihg‐performance Alkyd System 2000, which incorporates a new binder type, is available in 14 standard colours, inmcluding white.