Isolation and characterisation of 2-Tert-butyl-8-hydroxyquinoline as a crystalline solid and its blue fluorescent Li complex

Copyright © 2014 Poopathy Kathirgamanathan et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.2-Tert-butyl-8-hydroxyquinoline (2-TB-8-hq) has been isolated as a crystalline solid and its X-ray structure elucidated, resolving three decades of controversy, since it was previously wrongly reported as yellow oil by some other workers. An improved synthetic method has been developed which increases the yield from 20% to 60%. The lithium complex of 2-TB-8-hq is blue emitting and the HOMO and LUMO levels are lowered by 0.86 eV and 0.74 eV, respectively, compared with the parent lithium 8-hydroxyquinolinolate (Li 8-hq)

Can Mixed Ligand and Catalytic Solvent Effects Transform Single Electron Transfer Living Radical Polymerization (SET-LRP) into a Commercializable Process?

Currently most of the SET-LRP and ATRP techniques uses tris(2-dimethylaminoethyl)amine (Me6-TREN) as ligand which is 80 time more expensive than its precursor tris(2-aminoethyl)amine (TREN). TREN is much less expensive than Me6-TREN but at the same time is much less efficient, thus limiting the commercial applications of SET-LRP and ATRP mediated by TREN.1-6 In this work the efficiency of TREN was increased via two mechanisms: (i) the mixed ligand effect, (ii) the catalytic effect of solvent. Me6-TREN and TREN mixed ligand effect was studied in programed “biphasic” mixtures of the dipolar aprotic solvents N-methylpyrrolidone (NMP), dimethylformamide (DMF) and N,N-dimethylacetamide (DMAc) with H2O and in the homogenous dimethyl sulfoxide (DMSO) system with methyl acrylate(MA) as monomer, initiated by bis(2-bromopropionyl)-ethane (BPE). From the kinetic studies, molecular weight evolution and chain end analysis it was concluded that Me6-TREN complemented TREN to enhance its apparent rate constant of propagation, monomer conversion, and molecular weight control in the absence of externally added Cu(II)Br2. The catalytic effect of DMSO was studied with Me6-TREN, mixed-ligand and TREN and a liner external order of reaction was observed. The catalytic activity of DMSO in SET-LRP with near 100% chain end revitalized TREN as an excellent ligand in SET-LRP. Since the highest rate of reaction in mixed-ligand system is observed at a 1/1 ratio of ligands, this suggested three possible mechanisms: (i) either a fast exchange of ligands in the catalytic system, (ii) a new single dynamic ligand generated by hydrogen-bonding of the two ligands, (iii) or a combination of both (i) and (ii)

Discovery of two new phases of zirconium tetrakis(8-hydroxyquinolinolate): synthesis, crystal structure and their electron transporting characteristics in organic light emitting diodes (OLEDs)

Two new phases of zirconium tetrakis(8-hydroxyquinolinolate) (Zrq4) have been synthesised and characterised by single crystal X-ray diffraction. Their electrical, electronic, optical and thermal properties have been studied. Their electron transporting characteristics have been investigated in organic light emitting devices where the two phases show remarkable differences in performance. One of the forms (designated a-Zrq4) gives significantly lower operating voltage, higher efficiencies and longer lifetime than the other (designated b-Zrq4) in organic light emitting devices.EPSR

Novel lithium Schiff-base cluster complexes as electron injectors: synthesis, crystal structure, thin film characterisation and their performance in OLEDs

This journal is © The Royal Society of Chemistry 2012A set of novel lithium Schiff base cluster compounds has been synthesised and characterised for the first time and tested as electron injectors in OLED devices. Their electrical, electronic, thermal and optical properties have been investigated and compared with the industry standards LiF and lithium quinolinolate (LiQ). Amongst the compounds tested, lithium 2-((o tolylimino)methyl) phenolate was found to enhance the efficiency of OLEDs by 69% compared to LiF and 15% compared to LiQ. The same electron injector was found to extend the lifetimes of OLEDs by six-fold compared to LiF and 4.3- fold compared to LiQ respectively. The crystal structure of the parent compound, lithium 2- ((phenylamino)methyl)phenolate reveals that the compound is tetrameric in contrast to hexameric LiQ. Substituting the methyl group with fluorine causes a remarkable depression of the HOMO and LUMO levels by up to 1.2 eV. Analysis of current density vs. voltage characteristics of single-layer devices for Li–Al/electron injector/Li–Al and Al/electron injector/Al reveals that both sets of devices are operating as electron-only devices indicating that the formation of free lithium is the cause of enhanced electron injection, but either the energetic aluminium atoms (as proposed previously by other workers) or energetic lithium complexes on an aluminium surface (as we have demonstrated in this paper) are all that is required for efficient electron injection

Descriptive study to assess the awareness of ill effects of consanguineous marriage on pregnancy, fetus and child in antenatal mothers

Background: Consanguinity  refers to marriage or a reproductive relationship between two closely related individuals. Consanguinity may significantly impact the occurrence of autosomal recessive conditions and congenital anomalies. The degree of relatedness between two individuals defines the proportion of genes shared between them. Hence this study was planned to assess the awareness level, the association between awareness level and education, association between awareness level of and socioeconomic class.Methods: Direct interview through a self-structured questionnaire containing questions about demographic details, awareness of participants was conducted among (n=100) antenatal mothers attending SMC-OBG, OPD using convenient sampling. Knowledge of ≥50% is considered adequate. Data entry and analysis done using SPSS 16.0 software.  Descriptive statistics were calculated for background variables like socio-demographic characteristics. p value less than 0.05 were considered to be statistically significant.Results: 54% have an educational qualification above high school. 58% belonged to the lower socioeconomic strata. 67% had adequate knowledge. Out of the 26 people who have had consanguineous marriage, 30.8% have 2’ consanguinity, 69.2% have 3’ consanguineous marriage. Participants having educational status above high school have 1.7 times more knowledge than lesser educational qualification. People of higher socioeconomic status have 3.2 times more knowledge than lower socioeconomic status. Association between knowledge with socioeconomic status is significant.Conclusions: The target population has divergent attitudes towards consanguinity, though the awareness was decently high among many of them. Strategies to disseminate information in school programmes should be taken into consideration. Couples in consanguineous relationships can be identified, provided with information about their risk and, if needed referred for genetic counselling.

Study of whole body and hand-arm vibration in a small tractor with implements

Mechanization is the main solution to increase work output and also to improve the timeliness of operations. In this regard, tractors are the major prime movers in Indian farms. The sale of tractors in the country was 894112 units in 2023, with exports of 97745 units. The vibration studies have been conducted for tractors of higher horsepower and power tillers, which showed that continuous operation may result in health problems to the operator. Labour shortage has triggered the use of machinery and a safe and comfortable workstation is necessary to improve and increase productivity. Hence, the study on the vibration level of small tractors will aid in reducing the risk of health hazards and in designing safety measures for the tractor operator. The whole body and hand harm vibration studies were conducted at selected speed levels using cultivator and rotavator with 20.13 kW Force tractor and 17.89 kW Kubota tractor. Instruments used to measure whole body and hand-arm vibration were B & K portable four-channel PULSE Multi-analyser 3560 C, Biometrics Data LOG (MWX8) and Accelerometer S2A-16G-MF. The whole body vibration was exceeding the exposure action value of 0.5 ms-2 and Exposure Limit Value of 1.15 ms-2 while operating the cultivator, but within the limits when operating the rotavator. The hand-arm vibration was within the Exposure Action Value of 2.5 ms-2 and Exposure Limit Value of 5 ms-2 for the force tractor. Similar results were obtained for the Kubota tractor; however, the vibration was less than that of the force tractor

A study of factors determining outcome of acute kidney injury patients requiring hemodialysis

Background: High mortality rate in acute kidney injury (AKI) has interested many authors to conduct studies about factors predicting its outcome. The need for both dialysis and ICU care defines a group of critically ill patients who may have poor prognosis and consume vast amounts of resources. In this study we determine the variables predicting the outcome of patients with severe acute kidney failure requiring haemodialysis and to ascertain the aetiology of acute kidney injury in this group.Methods: We prospectively analysed 114 patients admitted with severe renal failure requiring renal replacement therapy over a period of one year. The influence of various factors such as demographic variables, pre morbidities, details of admission, clinical presentation and extent of organ dysfunction on the clinical outcome such as mortality and progression to end stage kidney disease were statistically analyzed using SPSS version 12 (SPSS Inc., Chicago, Ill).Results: Univariate and multivariate analysis showed that parameters such as chronic liver disease, preexisting heart disease, mechanical ventilation and vasopressor requirement, oliguria, sepsis, hepatorenal syndrome, cardiogenic shock and admission in ICU were associated with high mortality (p<0.05). Of the 114 patients, 49 died (42.98%), 61 (53.5%) were dialysis independent and 4 patients (3.5%) progressed to end stage renal disease (ESRD).Conclusions: AKI patients requiring hemodialysis were associated with high hospital mortality.  Patients who were diagnosed to have acute glomerulonephritis especially rapidly progressing glomerulonephritis as the cause of AKI were more prone to ESRD. Most survivors were dialysis independent at the time of discharge

Intraarticular use of tranexamic acid during primary total knee arthroplasty

Background: Tranexamic acid (TXA) is effective in reduction of blood loss after major surgical procedures. In TKA surgeries, it is commonly administered intravenously. Since there are contraindications of systemic use of TXA, local/intraarticular TXA can also be used. The efficacy of both systemic and local TXA administration is demonstrated in the literature. The aim was to assess the effect of intraarticular TXA during total knee arthroplasty in terms of total blood loss and transfusion rate. Methods: A total of 50 TKA in 34 patients were included in this prospective study.  Patients received one dose of intraarticular TXA of 3 g after skin closure and before deflation of the tourniquet. Results: The mean total blood loss in intra-articular TXA was 456.9 ml. None of the patients required transfusion postoperatively including those who underwent bilateral staged TKR. Mean postoperative hemoglobin loss was 1.07. Conclusions: TXA reduced blood loss and transfusion requirement. Intra-articular administration of TXA seems to be more effective in terms of reducing total blood loss and transfusion rates. We recommend administration of topical TXA in primary TKA in healthy patients to decrease perioperative blood loss

Film coefficient of heat transfer of Freon-12 condensing inside a single horizontal tube

Digitized by Kansas State University Librarie

Engineering hydrophobically modified chitosan for enhancing the dispersion of respirable microparticles of levofloxacin

The potential of amphiphilic chitosan formed by grafting octanoyl chains on the chitosan backbone for pulmonary delivery of levofloxacin has been studied. The success of polymer synthesis was confirmed using FT-IR and NMR, whilst antimicrobial activity was assessed against Pseudomonas aeruginosa. Highly dispersible dry powders for delivery as aerosols were prepared with different amounts of chitosan and octanoyl chitosan to study the effect of hydrophobic modification and varying concentration of polymer on aerosolization of drug. Powders were prepared by spray-drying from an aqueous solution containing levofloxacin and chitosan/amphiphilic octanoyl chitosan. L-leucine was also used to assess its effect on aerosolization. Following spray-drying, the resultant powders were characterized using scanning electron microscopy, laser diffraction, dynamic light scattering, HPLC, differential scanning calorimetry, thermogravimetric analysis and X-ray powder diffraction. The in vitro aerosolization profile was determined using a Next Generation Impactor, whilst in vitro antimicrobial assessment was performed using MIC assay. Microparticles of chitosan have the property of mucoadhesion leading to potential increased residence time in the pulmonary mucus, making it important to test the toxicity of these formulations. In-vitro cytotoxicity evaluation using MTT assay was performed on A549 cell line to determine the toxicity of formulations and hence feasibility of use. The MTT assay confirmed that the polymers and the formulations were non-cytotoxic. Hydrophobically modifying chitosan showed significantly lower MIC (4-fold) than the commercial chitosan against P. aeruginosa. The powders generated were of suitable aerodynamic size for inhalation having a mass median aerodynamic diameter less than 4.5 lm for formulations containing octanoyl chitosan. These highly dispersible powders have minimal moisture adsorption and hence an emitted dose of more than 90% and a fine particle fraction (FPF) of 52%. Powders with non-modified chitosan showed lower dispersibility, with an emitted dose of 72% and FPF of 20%, as a result of high moisture adsorption onto the chitosan matrix leading to cohesiveness and subsequently decreased dispersibility