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Melatonin (MT) has been reported to regulate certain plant physiological processes and promote tolerance to different environmental stresses such as salinity. Green bean (Phaseolus vulgaris L. cv. Royal Nel) seedlings were exposed to 200 mM NaCl with or without pre-treatment with 150 μM MT. Salt stress led to a lower chlorophyll content, a reduced photosynthetic activity, increased reactive oxygen species (ROS) contents, and decreased photosystem II (PSII) activity. The application of exogenous MT to green bean seedlings under salt stress improved photosynthetic activity and alleviated the oxidative damages by enhancing the activity of antioxidant enzymes. The expression of catalase (CAT1), glutathione reductase (GR), superoxide dismutase (CuZnSOD1), ascorbate peroxidase (APX), Peroxiredoxin Q (PrxQ), and 2-cysteine peroxiredoxin (2-Cys-Prx) encoding genes was significantly increased under salt stress in green bean seedling compared with the untreated control. However, plants treated with exogenous MT and NaCl had 28.8, 21.1, 26.1, 20, 26.2, and 22.4% higher CuZnSOD, CAT1, APX, GR, PrxQ, and 2-Cys-Prx transcript levels, respectively, compared to NaCl stress alone. Our study revealed the protective mechanisms mediated by exogenous MT application in NaCl stress alleviation and our findings could be used in the management of green bean cultivation in salinity-prone soils.

Microbial fuel cells (MFCs) produce electricity as a result of the microbial metabolism of organic substrates, hence they represent a sustainable approach for energy production and waste treatment. If the technology is to be implemented in industry, low cost and sustainable bioelectrodes must be developed to increase power output, increase waste treatment capacity, and improve service intervals. Although the current application of abiotic electrode catalysts, such as platinum and electrode binders such as Nafion leads to greater MFC performance, their use cost prohibitive. Novel bioelectrodes which use cost effective and sustainable materials are being developed. These electrodes are developed with the intention to reduce start‐up time, reduce costs, extend life‐span and improve core MFC performance metrics (ie. power density, current density, chemical oxygen demand (COD) reduction and Coulombic efficiency (CE)). Comparison of different MFC systems is not an easy task. This is due to variations in MFC design, construction, operation, and different inocula (in the case of mixed‐culture MFCs). This high intra system variability should be considered when assessing MFC data, operation and performance. In this review article, we examine the major issues surrounding bioanode and biocathode improvement in different MFC systems, with the ultimate goal of streamlining and standardising improvement processes.

BACKGROUND: Many approaches have been employed to increase the understanding and consequently the performance of Microbial Fuel Cells to obtain simultaneous power production and biodegradation. This study uses recombinant Escherichia coli K-12 with MtrA, MtrC and MtrCAB inserts previously prepared using synthetic biology to evaluate the involvement of each of these genes in bioenergy production and biodegradation of Congo red using a double chamber microbial fuel cell. RESULTS: MtrC was the key gene required for energy production corresponding to an average voltage of 360 mV (external resistance 1 K&) and power density of 59 mW/m2, while E. coli with MtrCAB insert showed the highest decolourisation which reached 80% in 36 h under microbial fuel cells conditions. Coloumbic efficiency was 1.2% for E.coli with MtrCAB compared to 2.5% and 2.3% for MtrC and MtrA inserts, respectively. Riboflavin seems to be involved in the electron transferring, its concentration was highest for E.coli with MtrA insert despite its poor performance in both bioenergy production and dye degradation. CONCLUSION: This study suggests that electrons are mutually exclusive between electricity production, dye degradation and other cellular activities. This study helps us improve our understanding of the dual bioenergy/decolourisation process taking place in MFCs in order to maximize the outcome.

A series of hybridized pyrrolidine compounds with a 1,2,4-oxadiazole moiety were synthesized to develop effective molecules against the enzymes DNA gyrase and topoisomerase IV (Topo IV). Compounds 8-20 were developed based on a previously disclosed series of compounds from our lab, but with small structural modifications in the hopes of increasing the compounds' biological activity. In comparison to novobiocin, with IC

A series of 1,3,4-oxadiazole-1,2,3-triazole hybrids bearing different pharmacophoric moieties has been designed and synthesized. Their antiproliferative activity was evaluated against four human cancer cell lines (Panc-1, MCF-7, HT-29, and A-549) using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The preliminary activity test displayed that the most active compounds, 6d, 6e, and 8a-e, suppressed cancer cell growth (GI

Electrical properties of some sandstone rocks (conductivity and dielectric constant) were investigated as a function of frequency (100 Hz to 100 kHz). Such heterogeneous specimens contain semiconducting constituents (silt and clay) and insulating constituents (sand, air, and carbonates). A theoretical pseudo-random renormalisation group method was used to predict the electrical properties of such random mixture. Four phases were used in the model to consider the detailed texture of the constituent materials. The measured electrical properties (conductivity and dielectric constant) versus frequency of these samples were analysed to predict the texture or connections of these four phases. From the analysis, these four phases were suggested to be (1) carbonates, (2) sand coated with clay and coated with air, (3) carbonates coated with clay and coated with air, and (4) pure sand. The forward problem predicts the electrical properties versus frequency using the pseudo-random renormalisation group method for certain concentrations of the constituent materials distributed among the random four phases. The forward model is used to fit the measured response to obtain the expected concentrations of rock constituents in the proposed four phases using a parameter search method (inverse problem). The obtained accordance between the experimental and modelled characteristics in much of the frequency band used suggests that the pseudo-random renormalisation group method with the supposed four phases reasonably represents the main mineralogical composition of the rock.

Diaminomaleonitrile and N-arylbenzamidrazones reacted together to give 4-amino-5-iminopyrazoles. A probable reaction mechanism involves firstly removal of ammonia, followed by addition and cylization of the hydrazino-N2 of amidrazone to the nitrile group in diaminomaleonitrile. The structure of the obtained products was proved by IR, mass, NMR spectra and elemental analyses.

A green approach was developed for synthesizing a series of (isatin-3-ylidene)-hydrazonamides 3a-j from the reaction between isatin, (isatin-3-ylidene)malononitrile, or 2-cyano-2-(2-isatin-3-ylidene)acetate and benzohydrazonamide in ethyl acetate solutions at ambient temperature. The structures of the new compounds were confirmed on the basis of spectral data. In this eco-friendly medium, a variety of (isatin-3-ylidene)hydrazonamides were obtained free of catalyst in good to excellent yields. All the synthesized products were evaluated for their antimicrobial activity. Among the compounds tested, 3b and 3d exhibited good antibacterial activity against Staphylococcus aureus, whereas others responded moderately with reference to the standard drug ciprofloxacin.

Understanding petrographical, geochemical and electrical properties of rocks is essential for investigating minerals. This paper presents a study of the petrographical, geochemical and A.C. electrical properties of carbonate rock samples. The samples collected show six lithostratigraphic rock units. Electrical properties were measured using a non-polarizing electrode at room temperature (∼20°C) and a relative atmospheric humidity of ∼50% by weight in the frequency range from 42 Hz to 5 MHz. The difference in electrical properties between the samples was attributed to the change in composition and texture between the samples. Electrical properties generally change with many factors (grain size, chemical composition, grain shape and facies). The dielectric constant decreases with frequency and increases with conductor composition. The conductivity increases with the increase of conductor paths between electrodes. Many parameters can contribute to the same result of the electrical properties. The main objective of the present study is to shed more light on the relation between the texture and geochemical composition of measured samples (carbonates that contain clays and quartz grains) through electrical laboratory measurements (conductivity and dielectric constant as a function of frequency).

This paper is devoted to study the effect of saturation, with distilled water, on AC electrical conductivity and dielectric constant of a fully and partially saturated hematitic sandstone sample (Aswan area, Egypt). The saturation of the sample was changed from full saturation to partial saturation by air drying. Complex resistivity measurements at room temperature (∼16 ◦ C) were performed in the frequency range from 10 Hz to 100 kHz. We used non-polarizing Cu/CuSO4 gel electrodes. Experimental electrical spectra indicate, generally, that the electrical conductivity and dielectric constant vary strongly with water saturation and frequency. The low-frequency electrical conductivity and dielectric constant are supposed to be mainly controlled by surface conduction and polarization of the electrical double layer. Power law behaviours with frequency were noticed. The change in electrical conductivity and dielectric constant with increasing water content is fast at low saturations and slow at high saturations. The behaviour of the electrical conductivity and dielectric constant, with increasing water content, was argued to be the orientational polarization of bound water for very low saturations, displacement of the excess surface charges for relatively low saturations and free exchange of excess ions in double layer with the bulk electrolyte and generation of transient diffusional potentials, which lag behind the applied field for high saturations in addition to membrane polarization on clay and at inter-grain and grain surface water throats having selective charge transport properties. Also, from the data a semi-percolation behaviour was found that has a peak of dielectric constant at a certain concentration and an abrupt change in conductivity at another saturation.

The thermal effects of magmatic intrusion on the conductivity and dielectric constant of magnetic rocks from Hammamat sediments, NE desert, Cairo, Egypt (latitude ∼27° and longitude ∼33°) were investigated experimentally in the laboratory using non-polarizing electrodes. Granitic magma was intruded into the Hammamat sediments, which are a mixture of mainly magnetite with sandstone and due to the thermal effect the area around was extensively heated and altered to different degrees. Due to this magma intrusion, magnetite was transformed (by heating) to hematite to different degrees according to its location from the intrusion. Complex impedance measurements were performed in the frequency range of 10 Hz to 100 KHz at normal temperature (∼20°C) and at a relative humidity of ∼50% RH. Samples were collected at different locations perpendicular to the core of the magma intrusion. Experimental data indicate that the electrical properties vary strongly as we move away (with distance) from the magma intrusion. The conductivity of hematite is ∼10- 2 S/m and that of magnetite is ∼10 4 S/m. As we move from magnetite to hematite (to the core of the magma intrusion) it is supposed that the conductivity will decrease but it was found that the conductivity increases (which is supposed to be abnormal). The conductivity increases with increasing frequency from ∼10 -8 S/m to ∼10 -5 S/m with almost power-law dependence on frequency. The conductivity increases in the order of one decade due to the variation from magnetite to hematite. The increase of conductivity, as we move from magnetite to hematite, was argued to be due to the heating that partially or completely melts the samples, thus the porosity of the samples was decreased and accordingly the conductivity and dielectric constant increased. It was also supposed that the grains of the conductor in the samples are coated or isolated with insulator material. A percolation behaviour for the conductivity and dielectric constant, characteristic of random conductor-insulator mixtures, was found with distance, where continuous paths of the conductive material occur accompanied by peaking of the dielectric constant. Complex impedance plots show that as we move in the direction of altered samples (towards hematite) the relation between real and imaginary impedance changes from a linear form to an arc of a depressed semicircle and increases in depression as we move in the direction of the altered samples, which is consistent with the above interpretation.

Nucleophilic attack by N2 of N1 N2-diarylformamides 1a-c on C-2 of chloranil (2) and subsequently by N1 on C-1 of 2 initiates the formation of benzimidazolinones 8a-c. In contrast, when 1b-e is reacted with 2,3-dichloro-1,4-naphthoquinone (9), both chlorine atoms are successively substituted by the two nitrogen atoms and 2-(arylamino)-3-(N-formylarylamino)-1,4-naphthoquinones 13b-e result, which (probably via their cyclic tautomers 12b-e) may be cyclodehydrogenated to form N1,N3-diarylnaphtho[2,3-d] imidazoline-2,4,9-triones (as 14b,c). On the other hand, N1,N2diarylacetamidines 15a-d attack 2 and 9 at C-2 with N2 but subsequently exert nucleophilic character at the acetamidine α-carbon attacking C-1 of 2 and 9, respectively, thus forming 1-aryl-2-(arylimino)-3a-hydroxy-2,3,3a,6-tetrahydro-1N-indol-6-ones 18a-d and 3-aryl-2-(arylimino)-9b-hydroxy-2,3,5,9b-tetrahydro-1-H-benz[e]indol-5-ones 19b,c, respectively. The latter may be thermally dehydrated to the fully conjugated 2,5-dihydro-3H-benz[e]indol-5-ones 20b,c. Unambiguous structural assignments for 18b and 20c are made on the basis of X-ray crystal structure analyses.

This paper presents a brief summary of the Organic Chemical, Plastics, and Synthetic Fibers (OCPSF) regulations and a 10 point plan for compliance with the regulations. Several practical examples are discussed concerning the application of this plan to actual facilities with emphasis placed on waste minimization methods.

6-Benzoyl-1-aryl-4-phenylpyridin-2(1H)-ones 8a–c together with the corresponding 2-aryl-1,4-diphenylbut-2-ene-1,4-diones 9a–c were obtained from the reaction of N 1 ,N 2 -diarylacetamidines 1a–c with dibenzoylacetylene 2, while reaction of 1a,b with dimethyl acetylenedicarboxylate 11a and methyl propiolate 11b afforded only the acetamidine–dimethyl maleate adducts (E)-12a,b and the acetamidine–methyl acrylate adduct (E)-12c respectively.

2-Bromo-1-{aryl[1-(arylimino)ethyl]amino}-1-phenylethanol derivatives 3a, 3b were obtained from the reaction of N1,N2-diarylacetamidines 1a, 1b with α-bromoacetophenone 2, while 1a, 1b with ethyl 2-bromoethanoate 4 afforded 2-{[1-(arylimino)]ethyl}aminoethanoic acid derivatives 5a, 5b; N1,N2-diarylformamidines 6a, 6b reacted with 2 and 4 to give the arylaminoacetophenones 8a, 8b and N-arylglycine ethyl esters 11a, 11b respectively together with the corresponding formanilides 9a, 9b.

1′-Aryl-6′-arylimino-2,2′-dioxospiro[(2,3-dihydro-1H-indole)-3,4′-perhydropyridine]-3′-carbonitriles 5a—d together with ethyl 2-amino-4-[1-aryl-2,6-bis(arylamino)-4-hydroxy-1,4-dihydro-4-pyridyl]quinoline-3-carboxylate 9a—c were obtained from the reaction of N1,N2-diarylacetamidines 1a—d with ethyl 2-oxoindoline-3-ylidenecyanoacetate 3. Acetamidines 1a—c also reacted with the benzylidenemalononitriles 10a—d to afford the adducts 1,4,5,6-tetrahydropyridines 13a—f.

2-Arylamino-2-(3-methyl-5-oxo-1-phenyl-1,5-dihydro-4H-pyrazol-4-ylidene)ethanenitriles (6a–c) together with the corresponding formanilides (7a–c) are formed in the reaction of N1,N2-diarylformamidi...

1-Cyclohexyl-2-cyclohexylaminomethylene-4,5-diphenyl-1,2-dihydropyrrol-3-one 4a and 1-aryl-2-arylaminomethylene-4,5-diphenyl-1,2-dihydropyrrol-3-ones 4b,c as the E-form are synthesized by the reaction between N,N′-dicyclohexylethane-1,2-diylidenediamine 2a and N,N′-diarylethane-1,2-diylidenediamines 2b,c with diphenylcyclopropenone 1 through a formal [2 + 3] cycloaddition reaction. The structure assignment of 4a is confirmed on the basis of an X-ray crystal-structure determination. Similarly, diaryl azines 8a–c react with 1 through a formal [2 + 3] cycloaddition reaction to give the non-isolable product Δ4-pyrrolin-3-ones 10a–c which undergo oxidative rearrangement to afford ultimately the indenone derivatives 9a–c.

The principal emission source of nitrogen oxides (NOx) and carbon monoxide (CO) from ethylene plants is the pyrolysis furnace. This paper addresses NOx/CO emissions and controls for gas fired pyrolysis furnaces. Typical NOx and CO generation rates for furnaces are quantified. The impact of fuel coposition on NOx generation is discussed. Commercially available and emerging control technologies are reviewed. The relative costs of these controls are compared. Case-by-case considerations will dictate the selection of the control technology required to comply with the environmental demands of the specific site.

Novel spiro[fluorene-9,4′-(1′,2′,3′,4′-tetrahydropyridine)]-5′-carbonitriles 6a-c have been obtained from the reaction of N1,N2-diarylacetamidines 1a-c with (2,4,7-trinitro-9H-fluoren-9-ylidene)propanedinitrile (2) in ethyl acetate solutions at ambient temperature for 6a,b or under reflux for 6c, respectively.

Substituted thiosemicarbazones 7a–e reacted with ethenetetracarbonitrile (TCNE) in ethyl acetate with formation of 5-amino-3-(substituted ben-zylidene-amino)-2-phenylimino-2,3-dihydrothiazole-4-carbonitrile 8a–e 2-amino-6-phenyl-imino-1,6- dihydropyrrolo[1,3,4]thiadiazine-3-carbonitrile 9, and phenyl-(5-{substituted phenyl}-3H-[1,3,4]thiadiazole-2-ylidene)amines 10a–e. Rationales for the observed conversations are presented. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:261–266, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20198

The reaction of 2-aminomethylene-2,3-dihydropyrrol-3(1H)-ones with ethyl bromoacetate, chloroacetonitrile, or dilute HCl gave rise to a series of methine dyes, namely 1-aryl-2-[3-hydroxy-1-aryl-4,5-diphenyl-1H-pyrrol-2-yl]methylene-4,5-diphenyl-2,3-dihydropyrrol-3(1H)-ones.