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Geosynthetic clay liners (GCLs) are mostly used as flow barriers in landfills and waste containments due to their low hydraulic conductivity to prevent the leachate from reaching the environment. The self-healing and swell-shrink properties of soft clays (expansive soils) such as bentonite enable them as promising materials for the GCL core layers. However, it is important to modify their physico-chemical properties in order to overcome the functional limitations of GCL under different hydraulic conditions. In the present study, locally available black cotton soil (BCS) is introduced in the presence of an anionic polymer named carboxymethyl cellulose (CMC) as an alternative to bentonite to enhance the hydraulic properties of GCL under different compositions. The modified GCL is prepared by stitching the liner with an optimum percentage of CMC along with various percentages of BCS mixed with bentonite. Hydraulic conductivity tests were performed on the modified GCL using the flexi-wall permeameter. The results suggest that the lowest hydraulic conductivity of 4.58 × 10−10 m/s is obtained when 25% of BCS is blended with bentonite and an optimum 8% CMC and further addition of BCS results in the reduction of the hydraulic conductivity. HIGHLIGHTS Modification of bentonite with locally available black cotton soil and caboxymethyl cellulose polymer.; Enhancement of hydraulic performance of modified geosynthetic clay liner.; Sodium content is low in the modified bentonite beyond the optimum percentage of black cotton soil blended with carboxymethyl cellulose polymer.;

Objective: This study aims to evaluate the effects of two drill designs on insertion torque (IT) and implant stability quotient (ISQ) during osteotomy. Methodology: This in vivo animal study involved eight female New Zealand white rabbits divided into two groups: Group A underwent osteotomy using standard drills from the Zimmer surgical kit, and Group B used Densah drills. IT values and ISQ were taken during and after implant placement. Rabbits received premedication, and postoperative care was provided. Results: Significant differences in peak IT were observed between the two groups, with Group B demonstrating a statistically significant advantage. However, no significant differences were found in ISQ between the groups. Conclusion: This study highlights the potential benefits of osseodensification in enhancing primary stability during osteotomy.

Nodular hidradenoma is an uncommon benign skin tumor arising from sweat glands that most commonly present in the head and neck as an indolent protruding cutaneous nodule with external skin changes. More rarely, they may arise in the breast skin with characteristics that may mimic metaplastic carcinoma, resulting in a diagnostic dilemma for physicians. We report a case of breast skin nodular hidradenoma with an unusual presentation and initial concern for invasive metaplastic breast carcinoma on core-needle biopsy. We discuss the diagnostic challenges of this rare breast tumor with recommendations for future diagnostic strategies when concerned for skin-based breast lesions.

There is growing evidence that smoking cessation (SC) improves outcomes following diagnosis of cancer. Notwithstanding adverse outcomes, a significant number of those diagnosed with cancer continue to smoke. Our objective was to document the SC services provided for patients with cancer by specialist adult cancer hospitals across Ireland, a country with a stated tobacco endgame goal.A cross-sectional survey based on recent national clinical guidelines was used to determine SC care delivery across eight adult cancer specialist hospitals, and one specialist radiotherapy centre. Qualtrics was used.The response rate was 88.9% with data reported from seven cancer hospitals and one specialist radiotherapy centre, all indicating they had some SC related provision (100%). Stop smoking medications were provided to cancer inpatients in two hospitals, at outpatients and attending day ward services in one hospital. Smokers with cancer were referred automatically to the SC service in two hospitals at diagnosis. While stop smoking medications were available 24 h a day in five hospitals, most did not stock all three (Nicotine Replacement Therapy, Bupropion, Varenicline). One hospital advised they had data on uptake of SC services for smokers with cancer but were unable to provide detail.There is considerable variation in SC information and services provided to cancer patients across adult cancer specialist centres in Ireland, reflecting the suboptimal practice of smoking cessation for patients with cancer found in the limited international audits. Such audits are essential to demonstrate service gaps and provide a baseline for service improvement.

Abstract Mosquito borne diseases are on the rise because of their fast spread worldwide and the lack of effective treatments. Here we are focusing on the development of a novel anti-malarial and virucidal agent with biocidal effects also on its vectors. We have synthesized a new quinoline (4,7-dichloroquinoline) derivative which showed significant larvicidal and pupicidal properties against a malarial and a dengue vector and a lethal toxicity ranging from 4.408 µM/mL (first instar larvae) to 7.958 µM/mL (pupal populations) for Anopheles stephensi and 5.016 µM/mL (larva 1) to 10.669 µM/mL (pupae) for Aedes aegypti. In-vitro antiplasmodial efficacy of 4,7-dichloroquinoline revealed a significant growth inhibition of both sensitive strains of Plasmodium falciparum with IC50 values of 6.7 nM (CQ-s) and 8.5 nM (CQ-r). Chloroquine IC50 values, as control, were 23 nM (CQ-s), and 27.5 nM (CQ-r). In vivo antiplasmodial studies with P. falciparum infected mice showed an effect of 4,7-dichloroquinoline compared to chloroquine. The quinoline compound showed significant activity against the viral pathogen serotype 2 (DENV-2). In vitro conditions and the purified quinoline exhibited insignificant toxicity on the host system up to 100 µM/mL. Overall, 4,7-dichloroquinoline could provide a good anti-vectorial and anti-malarial agent.

Studies on externally bonded fibre reinforced polymer (FRP) strengthened/laminated reinforced concrete (RC) beams have been exhaustively carried out in recent past decades in various countries. And the method has been found effective in various aspects compared to other earlier structural strengthening methods. From the reported studies, the load-carrying capacity of such beams found often limited due to premature debonding types of failure of FRP composite. The above phenomenon also considerably affects the ductility properties of the beams. Enhancement of the flexural capacity of FRP strengthened beam, and to overcome the ductility depletion on the above-said beams is need of an hour. This paper proposes a technique in which short, discrete hooked-end steel fibres are added into the concrete mix and then strengthened with GFRP laminates to counteract the above enhancements bilaterally. An experimental investigation on externally GFRP bonded RC beams with steel fibres was conducted based on the above. Three different types of beams, namely, an unstrengthened RC beam; one GFRP strengthened RC beam; three GFRP strengthened RC beams added with hooked-end steel fibres in three different volume contents (0.5%, 1.0%, and 1.5%), were considered in this study. The parameters considered in this study are load, deflection, ductility property, and mode of failure of the beams. The finite element analysis (FEA) based beam models were developed using the ANSYS software and validated. The addition of steel fibres pats the potential of GFRP laminate and enhances the overall performance of strengthened beams to a greater extent.

Many of the several authors have reported that reinforced concrete (RC) beams strengthened with externally bonded fibre reinforced polymer (FRP) laminates/sheets considerably reduced its ductility due to increase in stiffness that leads to debonding type of failure without adequate prior notice. This study aims to investigate the strength and ductility of glass fibre reinforced polymer (GFRP) laminated RC beams incorporated with different volume fraction (Vf = 0.5, 1.0, and 1.5) of discrete steel fibres. From the experimental evaluations, the role played by the incorporation of steel fibres is found to be effective in enhancing both the strength and ductility of FRP strengthened beams at all level of volume fractions, used in this study. Finite element analysis based full-scale beam models were developed using ANSYS software to model the response of all beams, as well, and the load-deflection behaviour of the models exhibit good agreement with the experimental results.

The longevity of any reinforced concrete element is determined by the quality of the cover concrete. The only way for aggressive chemicals to get into the structural components and cause rebar corrosion and other types of damage is through the cover concrete. The controlled permeable formwork (CPF) liner is a unique approach for enhancing the quality of cover concrete. This liner permits surplus water and trapped air to escape while keeping the cement and fine particles in place on the concrete surface. Due to the modification, the water-cement (w/c) ratio is reduced, cement content is increased and surface porosity in the concrete cover zone is reduced. The influence of CPF liner on durability property and corrosion resistance of reinforced concrete was investigated in this study. Concrete samples were cast against a CPF liner and impermeable formwork (IMF) at three different water-cement ratios (0.47, 0.40, and 0.33). The rapid penetration of chloride, ingress of chloride, migration of chloride and accelerated corrosion were all examined at various ages. The results showed that CPF concretes exhibited good resistance to chloride ion intrusion of 46–56%. Furthermore, when casting of concrete is done with CPF liner, the time it takes for crack is 1.5 times longer than when concrete is cast against IMF.

An application specific integrated design using Quadrature Linear Discriminant Analysis is proposed for automatic detection of normal and epilepsy seizure signals from EEG recordings in epilepsy patients. Five statistical parameters are extracted to form the feature vector for training of the classifier. The statistical parameters are Standardised Moment, Co-efficient of Variance, Range, Root Mean Square Value and Energy. The Intellectual Property Core performs the process of filtering, segmentation, extraction of statistical features and classification of epilepsy seizure and normal signals. The design is implemented in Zynq 7000 Zc706 SoC with average accuracy of 99%, Specificity of 100%, F1 score of 0.99, Sensitivity of 98% and Precision of 100 % with error rate of 0.0013/hr., which is approximately zero false detection.

The title compounds, 4-(5-acetamido-3-acetyl-2-methyl-2,3-dihydro-1,3,4-thiadiazol-2-yl)phenyl benzoate, C20H19N3O4S (I), 4-(5-acetamido-3-acetyl-2-methyl-2,3-dihydro-1,3,4-thiadiazol-2-yl)phenyl isobutyrate 0.25-hydrate, C17H21N3O4S·0.25H2O (II), 4-(5-acetamido-3-acetyl-2-methyl-2,3-dihydro-1,3,4-thiadiazol-2-yl)phenyl propionate, C16H19N3O4S (III) and 4-(5-acetamido-3-acetyl-2-methyl-2,3-dihydro-1,3,4-thiadiazol-2-yl)phenyl cinnamate chloroform hemisolvate, C22H21N3O4S·0.5CHCl3 (IV), all crystallize with two independent molecules (A and B) in the asymmetric unit in the triclinic P\overline{1} space group. Compound II crystallizes as a quaterhydrate, while compound IV crystallizes as a chloroform hemisolvate. In compounds I, II, III (molecules A and B) and IV (molecule A) the five-membered thiadiazole ring adopts an envelope conformation, with the tetrasubstituted C atom as the flap. In molecule B of IV this ring is flat (r.m.s. deviation 0.044 Å). The central benzene ring is in general almost normal to the mean plane of the thiadiazole ring in each molecule, with dihedral angles ranging from 75.8 (1) to 85.5 (2)°. In the crystals of all four compounds, the A and B molecules are linked via strong N—H...O hydrogen bonds and generate centrosymmetric four-membered R44(28) ring motifs. There are C—H...O hydrogen bonds present in the crystals of all four compounds, and in I and II there are also C—H...π interactions present. The intermolecular contacts in the crystals of all four compounds were analysed using Hirshfeld surface analysis and two-dimensional fingerprint plots.

The title compound, C11H8O5·(CH3)2SO, is a new coumarin derivative. The asymmetric unit contains two coumarin molecules (A and B) and two dimethylsulfoxide solvent molecules (A and B). The dihedral angle between the pyran and benzene rings in the chromene moiety is 3.56 (2)° for molecule A and 1.83 (2)° for molecule B. In molecule A, the dimethyl sulfoxide sulfur atom is disordered over two positions with a refined occupancy ratio of 0.782 (5):0.218 (5). In the crystal, molecules are linked by O—H...O hydrogen bonds, forming chains running along the c-axis direction. The chains are linked by C—H...O hydrogen bonds, forming layers parallel to the ac plane. In addition, there are also C—H...π and π–π interactions present within the layers. The intermolecular contacts in the crystal have been analysed using Hirshfeld surface analysis and two-dimensional fingerprint plots, which indicate that the most important contributions to the packing are from H...H (33.9%) and O...H/H...O (41.2%) contacts.

The title compounds, 8-amino-6-methyl-3,4-diphenyl-1H-isochromen-1-one, C22H17NO2, (I), and 8-amino-3,4-diethyl-6-methyl-1H-isochromen-1-one, C14H17NO2, (II), are new isocoumarin derivatives in which the isochromene ring systems are planar. Compound II crystallizes with two independent molecules (A and B) in the asymmetric unit. In I, the two phenyl rings are inclined to each other by 56.41 (7)° and to the mean plane of the 1H-isochromene ring system by 67.64 (6) and 44.92 (6)°. In both compounds, there is an intramolecular N—H...O hydrogen bond present forming an S(6) ring motif. In the crystal of I, molecules are linked by N—H...π interactions, forming chains along the b-axis direction. A C—H...π interaction links the chains to form layers parallel to (100). The layers are then linked by a second C—H...π interaction, forming a three-dimensional structure. In the crystal of II, the two independent molecules (A and B) are linked by N—H...O hydrogen bonds, forming –A–B–A–B– chains along the [101] direction. The chains are linked into ribbons by C—H...π interactions involving inversion-related A molecules. The latter are linked by offset π–π interactions [intercentroid distances vary from 3.506 (1) to 3.870 (2) Å], forming a three-dimensional structure.

The title compounds, C27H20Br2N6O4·2H2O, (I), and C30H28N6O4·[+ solvent], (II), both crystallize with one half-molecule in the asymmetric unit. The whole molecule of (I) is generated by twofold rotation symmetry, with the twofold rotation axis bisecting the C atom of the –O—CH2—O– bridge. This results in a folded or U-shaped conformation of the molecule. The whole molecule of (II) is generated by inversion symmetry, with the central CH2—CH2 bond of the –O—(CH2)4—O– bridge being located about a center of inversion. This results in a step-like conformation of the molecule. The central C(=O)N—N=C regions of the isonicotinohydrazide moieties in both compounds are planar and the configuration about the imine C=N bonds is E. In compound (I), the benzene and pyridine rings are inclined to each other by 37.60 (6)°. The two symmetry-related pyridine rings are inclined to each other by 74.24 (6)°, and the two symmetry-related benzene rings by 7.69 (6)°. In compound (II), the benzene and pyridine rings are inclined to each other by 25.56 (11)°. The symmetry-related pyridine rings are parallel, as are the two symmetry-related benzene rings. In the crystal of (I), a pair of water molecules link the organic molecules via Owater—H...O and Owater—H...N hydrogen bonds, forming chains along [001], and enclosing an R42(8) and two R12(5) ring motifs. The chains are linked by N—H...Npyridine hydrogen bonds, forming a supramolecular framework. There are also a number of C—H...O hydrogen bonds, and C—H...π and offset π–π interactions [interplanar distance = 3.294 (1) Å] present reinforcing the framework. In the crystal of (II), molecules are linked by N—H...Npyridine hydrogen bonds, forming a supramolecular framework. Here too there are also a number of C—H...O hydrogen bonds present, and a C—H...π interaction, reinforcing the framework. For compound (II), a region of disordered electron density was corrected for using the SQUEEZE [Spek (2015). Acta Cryst. C71, 9–18] routine in PLATON. Their formula mass and unit-cell characteristics were not taken into account during refinement.

The title compounds, 2-(4-{2-[(2-oxo-2H-chromen-4-yl)oxy]acetyl}piperazin-1-yl)acetamide, C17H19N3O5, (I), and N-(2,4-dimethoxybenzyl)-2-[(2-oxo-2H-chromen-4-yl)oxy]acetamide, C20H19NO6, (II), are new coumarin derivatives. In compound (I), the six-membered piperazine adopts a chair conformation. The dihedral angles between the mean planes of the chromene ring and amide plane is 82.65 (7)° in (I) and 26.2 (4)° in (II). The dihedral angles between the mean planes of the chromene ring and the four planar C atoms of the piperazine ring in (I) and the benzene ring in (II) are 87.66 (6) and 65.0 (4)°, respectively. There are short intramolecular contacts in both molecules forming S(5) ring motifs, viz. N—H...N and C—H...O in (I), and N—H...O and C—H...N in (II). In the crystals of both compounds, molecules are linked by N—H...O hydrogen bonds, forming chains along [1\overline{1}0] in (I) and [010] in (II). The chains are linked by C—H...O hydrogen bonds, forming layers parallel to the ab plane in the crystals of both compounds. In the crystal of (I), there are also C—H...π and offset π–π interactions [intercentroid distance = 3.691 (1) Å] present within the layers. In the crystal of (II), there are only weak offset π–π interactions [intercentroid distance = 3.981 (6) Å] present within the layers. The intermolecular contacts in the crystals of both compounds have been analysed using Hirshfeld surface analysis and two-dimensional fingerprint plots.

In the title compounds, C32H25ClN2O4 (I) and C33H28N2O5 (II), the six-membered pyran and piperidine rings adopt envelope and chair conformations, respectively. The five-membered pyrrolidine rings adopt twist conformations. Compound (II) crystallizes with two independent molecules (A and B) in the asymmetric unit. In all three molecules there is a C—H...O intramolecular hydrogen bond present enclosing an S(7) ring motif. In (I), both oxygen atoms of the nitro group are disordered, while in (II) the methoxybenzene group is disordered in molecule B. The geometries were regularized by soft restraints. In the crystal of (I), molecules are linked by C—H...O hydrogen bonds, forming chains along [010]. The chains are linked by C—H...Cl hydrogen bonds, forming layers parallel to (10\overline{1}). Within the layer there are C—H...π interactions present. In the crystal of (II), the A and B molecules are linked via C—H...O hydrogen bonds, forming a square four-membered A–B–A–B unit. These units are linked by a number of C—H...π interactions, forming a three-dimensional supramolecular structure.

The title compound, C35H27ClN4O3, crystallized with two independent molecules (A and B) in the asymmetric unit. In both molecules, the pyran and pyridine rings adopt envelope and chair conformations, respectively. The conformation of the pyrrolidine and cyclopentene rings differ in the two molecules; twisted and flat, respectively, in molecule A, but envelope and twisted, respectively, in molecule B. In both molecules, there is a C—H...N intramolecular hydrogen bond present. In both molecules, the oxygen atoms of the nitro groups are disordered as is the chlorine atom in molecule B. In the crystal, the B molecules are linked by C—H...O hydrogen bonds, forming –B–B–B– chains along [010], and by C—H...π interactions. The A and B molecules are also linked by a number of C—H...π interactions, resulting in the formation a supramolecular three-dimensional structure. In molecule A, the nitro group oxygen atoms are disordered over two positions with refined occupancy ratios of the nitro group oxygen atoms O3A and O4A in 0.59 (2):0.41 (2) while in molecule B one of the nitro O atoms is disordered over two positions with a refined occupancy ratio of 0.686 (13):0.314 (13) and the chlorine atoms is disordered over two positions with a refined occupancy ratio of 0.72 (3):0.28 (3).

The kinetics of oxidation of methionine (Met) by tetraethylammonium chlorochromate (TEACC) in dimethyl sulfoxide (DMSO) leads to the formation of the corresponding sulfoxide. The reaction is first order each in Met and TEACC. The reaction is catalyzed by hydrogen ions. The hydrogen ion dependence has the form : kobs = a + b [H+]. The reaction rate has been determined at different temperatures and activation parameters are calculated. The solvent effect has been analyzed using Kamlet’s multi parametric equation. A correlation of data with Kamlet–Taft solvatochromic parameters (α, β, π∗) suggests that the specific solute–solvent interactions play a major role in governing the reactivity. The reaction does not induce polymerization of acrylonitrile. A suitable mechanism has been proposed.

In mobile ad hoc networks, communication among mobile nodes occurs through wireless medium The design of ad hoc network protocol, generally based on a traditional “layered approach”, has been found ineffective to deal with receiving signal strength (RSS)-related problems, affecting the physical layer, the network layer and transport layer. This paper proposes a design approach, deviating from the traditional network design, toward enhancing the cross-layer interaction among different layers, namely physical, MAC and network. The Cross-Layer design approach for Power control (CLPC) would help to enhance the transmission power by averaging the RSS values and to find an effective route between the source and the destination. This cross-layer design approach was tested by simulation (NS2 simulator) and its performance over AODV was found to be better.

ABSTRACT Aquatic weeds are higher plants found in the aquatic ecosystem and in anaerobic rice fields, where they have no economic benefits. The continuance of aquatic weeds is more widespread than terrestrial weeds because in aquatic ecosystems there is very little fluctuation in the environmental conditions compared with terrestrial ecosystems. Scientists have been working to address the harmful allelopathic effects of aquatic weeds on the aquatic ecosystem, but limited information is available on the allelopathic influence of aquatic weeds on agro-ecosystems through the release of phytotoxic compounds. Phytotoxic chemicals released by different aquatic weeds into irrigation water and/or directly into rice ecosystems might have a significant inhibitory influence on germination, growth and yield field crops, soil properties and nutrients availability, population and community structure, and weed invasion. However, aquatic weeds might also be used as a potential organic alternative to chemical weed-control, due to the higher susceptibility of terrestrial weeds to the phototoxic chemicals released by aquatic weeds. Natural alternatives to chemical weed control are need of time and are crucial for a sustainable weed control. Chemical weed control is challenged, due to recent increases in herbicides resistance from weeds and to the harmful side-effects of herbicides on the environment. This review is focused on the influence of aquatic weeds on agro-ecosystems, with examples of common weeds in aquatic ecosystems and invasive aquatic weeds found in anaerobic rice.

Triethylammonium chlorochromate (TriEACC) oxidation of some para-substituted benzhydrols (BH) in dimethylsulfoxide (DMSO) leads to the formation of corresponding benzophenones. The reaction was run under pseudo-first-order conditions. The reaction is catalyzed by hydrogen ions. The hydrogen ion dependence has the form: kobs = a + b[H+]. Various thermodynamic parameters for the oxidation have been reported and discussed along with the validity of isokinetic relationship. Oxidation of benzhydrol was studied in 18 different organic solvents. The rate data showing satisfactory correlation with Kamlet–Taft solvatochromic parameters (α, β and π∗) suggests that the specific solute–solvent interactions play a major role in governing the reactivity, and the observed solvent effects have been explained on the basis of solute–solvent complexation. A suitable mechanism of oxidation has been proposed.

Nanocomposite material that consists of DBSA (dodecylbenzensulfonic acid) doped polyaniline (PANI) was prepared by solvent free mechanochemical intercalation method. Organic aniline monomer was first intercalated into the interlayer regions of Na-MMT (sodium montmorillonite) clay hosts and followed by one-step oxidative polymerization. The as synthesized polyaniline clay nanocomposites were treated with DBSA to get PANI-DBSA clay nanocomposites. PANI-DBSA clay nanocomposites in the form of coatings at different concentrations of DBSA on C45 steel were found much superior in corrosion protection over those of conventional polyaniline, based on the series of electrochemical measurement of corrosion potential, polarization resistance and corrosion current in 3.5% aqueous NaCl electrolyte. UV–visible spectroscopy, FT-IR and SEM studies confirm the formation of intercalated polyaniline clay nanocomposites inside the clay nanolayers.

LTE-A (Long Term Evolution-Advanced) is the fourth generation technology to increase the speed of wireless data network. The LTE-A Physical layer provides both data and control information between an enhanced base station and mobile user equipment which is quite complex and consists of a mixture of technologies. Since there is requirement for more resources to accommodate all the channels in a single FPGA, Partial Reconfiguration (PR) technique is introduced to configure the total hardware into sub modules that configure and operate in different instants of time. PR enables a part of FPGA to be reconfigured, while the rest continues to function without any interruptions and reduces the hardware resource power and fabric area. This work proposes the realization of transmitter and receiver architecture of Physical Hybrid Indicator Channel (PHICH) channel for LTE-A using partial reconfiguration on xc6vlx240tff1156-1 FPGA. The receiver architecture for PHICH is to report the correct reception of uplink user data to the User Equipment (UE) in the form of Acknowledgment (ACK), or Negative ACK (NACK) in a 1 millisecond duration sub-frame of Long Term Evolution (LTE) System. The modules for the different diversities are reconfigured based on the control signals from the transmitter.

The oxidation of some aliphatic alcohols by triethylammonium chlorochromate (TriEACC) in dimethyl sulfoxide leads to the formation of the corresponding carbonyl compounds. The reaction is first order with respect to TriEACC. The reaction exhibited Michaelis–Menten type kinetics with respect to alcohol. The reaction is catalyzed by hydrogen ions. The hydrogen-ion dependence has the form: kobs = a + b[H+]. The oxidation of [1,1-2H2] ethanol (MeCD2OH) exhibits a substantial primary kinetic isotope effect. Oxidation of aliphatic alcohol was studied in 19 different organic solvents. The solvent effect has been analysed using Kamlet’s and Swain’s multi-parametric equation. A suitable mechanism has been proposed.

The oxidation kinetics of some para-substituted anilines by benzimidazolium fluorochromate (BIFC) have been studied in aqueous acetic acid media in the presence of perchloric acid. The reaction is first order with respect to both aniline and BIFC and is catalysed by a hydrogen ion. The rate data obey Hammett relationship. The products of oxidation are the corresponding azo benzenes. Based on the kinetic results and product analysis, a suitable mechanism has been proposed for the reaction of BIFC with anilines.

The kinetics of oxidation of some organic diols by tripropylammonium fluorochromate (TriPAFC) have been studied in dimethylsulfoxide (DMSO). The main product of oxidation is the corresponding hydroxy aldehydes. The reaction is first order with respect to TriPAFC and exhibited Michaelis-Menten type kinetics with respect to organic diols. The reaction is catalyzed by hydrogen ions. The hydrogen ion dependence has the form: kobs = a + b[H+]. Various thermodynamic parameters for the oxidation have been reported and discussed along with the validity of isokinetic relationship. Oxidation of diols was studied in 18 different organic solvents. The rate data are showing satisfactory correlation with Kamlet–Taft solvotochromic parameters (α, β and π∗). A suitable mechanism of oxidation has been proposed.

The kinetics of oxidation of methionine (Met) by benzimidazolium fluorochromate (BIFC) has been studied in the presence of chloroacetic acid. The reaction is first order with respect to methionine, BIFC and acid. The reaction rate has been determined at different temperatures and activation parameters calculated. With an increase in the mole fraction of acetic acid in its aqueous mixture, the rate increases. The solvent effect has been analyzed using the Kamlet’s multi parametric equation. A correlation of data with the Kamlet–Taft solvatochromic parameters (α, β, π∗) suggests that the specific solute–solvent interactions play a major role in governing the reactivity. The reaction does not induce polymerization of acrylonitrile. A suitable mechanism has been proposed.

3,4-Dihydropyrimidin-2(1H)-one, 3,4-dihydropyrimidin-2(1H)-thione, and 3,4-dihydropyrimidin-2(1H)-imine derivatives were synthesized by modified Biginelli cyclocondensation reaction catalyzed by triphenylphosphine as Lewis base. The structures of the synthesized compounds have been elucidated by IR, 1H NMR and elemental analysis.

Introduction : The premature loss of primary teeth may reduce arch length required for the succeeding tooth and, hence, predisposes crowding, rotation and impaction of the permanent teeth. There are only limited studies carried out about the prevalence of early loss of primary teeth. Aim : The present study was performed to evaluate the prevalence of early loss of primary teeth in school children in Chidambaram town in Tamilnadu, India. Settings and Design : A total of 1121 school children (561 boys and 560 girls) between 5 and 10 years of age were selected for the study. Materials and Methods : An experienced examiner performed all clinical examinations under natural light. Data including age and missing tooth was collected. Statistical Analysis Used : Microsoft Excel/2000 (Microsoft Office XP) data spreadsheet was used and later exported to the Statistical Package for Social Science (SPSS) for Windows (version 10.0). Descriptive statistics was applied and, from the results, chi-square tests were applied at a level of significance of 5% (P < 0.05). Results and Conclusions: The results showed that 16.5% of the sample had early loss of primary teeth, but no differences were observed between genders (P > 0.05). The greatest prevalence was found among the 8-year olds (5.08%), and the most commonly missing teeth were the right lower primary first molars (16.82%). It can be concluded that the prevalence of early loss was high and that the lower primary molars were the most commonly missing teeth in the present study

Polyaniline clay nanocomposite can be prepared by mechano-chemical method in which intercalation of anilinium ion into the clay lattices accomplished by mechanical grinding of sodium montmorillonite (Na+MMT) in presence of anilinium hydrochloride at room temperature using mortar & pestle for about 30 min and subsequent grinding with oxidizing agent, ammonium peroxysulfate. The appearance of green colour indicates the formation of polyaniline/clay nanocomposite (PANI/Clay). Similarly aniline derivatives like o-toludine and o-anisidine in the form of HCl salt can form intercalation into the clay lattices. The intercalated aniline derivatives were ground mechanically in presence of oxidizing agent ammonium peroxysulfate lead to formation of substituted polyaniline/ clay nanocomposites. The characteristics of various polyaniline-clay nanocomposites were investigated using UV-Visible, FT-IR, cyclic voltammetry studies.

The kinetics of oxidation of benzaldehyde (BA) and para-substituted benzaldehydes by imidazolium dichromate (IDC) has been studied in aqueous acetic acid medium in the presence of perchloric acid. The reaction is first order each in [IDC], [Substrate] and [H+]. The reaction rates have been determined at different temperatures and the activation parameters calculated. Electron withdrawing substituents are found to increase the reaction and electron releasing substituents are found to retard the rate of the reaction and the rate data obey the Hammett relationship. The products of the oxidation are the corresponding acids. The rate decreases with the increase in the water content of the medium. A suitable mechanism is proposed.

A new series of transition metal complexes of Cu(II), Ni(II), Co(II) and Zn(II) have been designed and synthesized using a Schiff base (L) derived from 4-aminoantipyrine, benzaldehyde and o-phenylenediamine. The structural features were derived from their elemental analyses, magnetic susceptibility and molar conductivity, as well as from mass, IR, UV–Vis, 1H-NMR and ESR spectral studies. The FAB mass spectral data and elemental analyses showed that the complexes had a composition of the ML type. The UV–Vis and ESR spectral data of the complexes suggested a square-planar geometry around the central metal ion. The magnetic susceptibility values of the complexes indicated that they were monomeric in nature. Antimicrobial screening tests were also performed against four bacteria, viz. Salmonella typhi, Staphylococcus aureus, Escherichia coli, and Bacillus subtilis and three fungi, viz. Aspergillus niger, Aspergillus flavus and Rhizoctonia bataicola. These data gave good results in the presence of metal ion in the ligand system. The nuclease activity of the above metal complexes shows that only the copper complex cleaves CT DNA in the presence of an oxidant.

The external bonding of fibre reinforced polymer (FRP) to reinforced concrete (RC) members has become a popular method of retrofitting/strengthening concrete structures in recent years. Extensive research has been conducted pertaining to RC beams strengthened with FRP laminates. However, the experimental studies on fibre reinforced concrete (FRC) beams strengthened using externally bonded FRP system are limited. The purpose of this research is to investigate the behaviour of steel fibre reinforced concrete (SFRC) beams strengthened with glass fibre reinforced polymer (GFRP) laminates. The beam specimens were incorporated with 1.0% volume fraction of short-steel fibres randomly distributed throughout the section. The beam cross-section was 150 mm wide and 250 mm deep and to a length of 3000 mm. All the beams were tested until failure. The study parameters of this investigation included service load, ultimate load, ductility, crack width and failure modes. Beams tested for this investigation consisted of reference (RC) beam, GFRP laminated RC beam, SFRC beam, and GFRP laminated SFRC beam. The test results showed that the SFRC beams strengthened with GFRP laminates exhibited better performance.