Studies in organobismuth chemistry

Perturbations in the bismuth market resulted in Mining and Chemical Products Ltd., seeking further outlets in the market. Together with Manchem Ltd. they were anxious to evaluate the possibility of using bismuth compounds as a replacement for lead/calcium soaps in paint driers. A range of new organobismuth compounds were synthesised of the type RBiX2 and R3BiX2 (X= halogen, OOCR, dithiocarbamate). A variety of synthetic techniques were explored, including the use of mathematical reactions, phase-transfer catalysis and microwave energy. The preparation of a range of trivalent and pentavalent organobismuth carboxylates is reported and their infra-red , 13C, lH nmr spectra. The compounds were evaluated as paint driers and in cases found to enhance paint drying to a greater degree than the standard driers, to which they were being compared. The drying times of paint films containing the organobismuth compounds are reported, together with a comparison of the drying times with the addition of bismuth tris-diethyldithiocarbamate, which may promote the cross-linking reaction that occur in paint films during the drying process. Examples are reported to illustrate the great reductions in reaction times possible when using microwave energy. Reactions such as metallation of aromatic rings, ligand redistribution and synthesis were carried out in PTFE containers in a conventional domestic microwave oven. An X-ray diffraction study of (phenylazophenyl-C,N')mercury(II) chloride has shown it to be dimeric via long Hg-Cl bridging interactions of 3.367A. Its crystal structure is reported, together with its 13C nmr spectra and mass spectrum. The Lewis acidity of compounds of the type RBiX2 was investigated. The donor group being anchored to the organo group (R). The dithiocarbamates bis- (diethyldithiobarbamato)phenylbismuth(Ill) and [2-2-pyridyl)phenylbismuth(III) were synthesised, and their crystal structures, 14N, 13C nmr ar1d infra-red spectra are reported. Both compounds are pseudo-pentagonal bipyramidal in geometry, with two long Bi-S bonds and two short Bi-S bonds. The reaction of RBiBr2 (R= 2-(pyridyl) with various ligands is reported. The infra-red evidence suggesting that the coordination of extra ligands is accompanied by a reduction of the strength of the Bi-interaction

Optimization and analysis of cutting parameters using cryogenic media in machining of high strength alloy steel

In this research, liquid Argon is used as a cryogenic media to optimize the cutting parameters for evaluation of tool flank wear width of Tungsten Carbide Insert (CNMG 120404-WF 4215) while turning high strength alloy steel. Robust design concept of Taguchi L9 (34) method is applied to determine the optimum conditions. This analysis revealed is revealed that cryogenic impact is more significant in reduction of the tool flank wear

Industrial Sector Input Demand Responsiveness and Policy Interventions

In Pakistan, government intervention in the input market of the industrial sector is considerable. It regulates prices of virtually all energy and certain other non-labour inputs. To stimulate industrial production and output growth, it also encourages the provision of extended credit facilities to the industrial producers. Further, it has also often announced adjustments/reductions in duties and tariffs on products used in industrial production. Conversely, government also imposes taxes on outputs. It may desire to levy new taxes on the industrial inputs. All interventions have profound implications for producers, consumers and the government alike. Therefore, it is important to know how they may affect the industrial input demand. Further, it is equally important to know how effective they may be for the government in the realisation of its objectives. The most pertinent approach to ascertain the industrial input demand responsiveness to government interventions is to obtain valid estimates of price elasticities. In fact, competent elasticity estimates of the producer input demand derived with a sound methodology can serve as a solid basis to predict producer responsiveness to market changes and thereby the effectiveness and desirability of government interventions. While the price elasticities of products over the years have been estimated for Pakistan, renewed interest on estimating responsiveness of producer input demand with modern estimation procedures has recently surged. Idrees (1997) and Khan (1998) have determined elasticities for the domestic large-scale manufacturing sector from a demand system. Although these research studies make a good addition to the literature, their scope is extremely limited because they have combined industrial inputs into large aggregates. At present, there is no study that has investigated the input demand elasticities of the domestic industrial sector at the dis-aggregated level.

IMPROVING PROJECT MANAGEMENT PLANNING AND CONTROL IN THE SERVICES OPERATION ENVIRONMENT BY USING THE 6S TECHNIQUE

In today's business land-scape, more is needed for companies to have a solid organizational system and values; they must also continuously improve their quality management systems to ensure zero accidents and complete safety. With intense competition among organizations to produce quality products, creating a positive and productive workplace for employees is a common challenge. Modern technology and the latest methods must be utilized to achieve desired goals and overcome industry challenges. One of the most modern and latest techniques available to organizations is the 6S methodology, which can help achieve industry goals. This study targets to assess the current level of project management planning and control, determine the awareness and understanding of the 6S methodology, and evaluate its impact on project management planning and control. We have chosen a questionnaire methodology for this quantitative research to examine the relationship between familiarity with the 6S methodology and its implementation in a service operating environment. This study will provide insights and recommendations on incorporating the 6S methodology into project management planning and control in a service operating environment. To ensure the successful implementation of the 6S methodology, organizations should provide adequate training and resources to their project management teams and encourage collaboration and communication among team members

Anti-diabetic potential of aerial parts of Galium tricornutum (Dandy) Rubiaceae

Purpose: To evaluate the anti-diabetic potential of methanol extract of the aerial parts of Galium tricornutum (Dandy) in diabetic rats.Methods: The methanol extract of the aerial parts of Galium tricornutum was first subjected to acute toxicity studies. Thereafter, the effect of the extract on oral glucose tolerance was determined. In addition, the effect of the extract on fasting blood glucose, as well as serum lipid profile, urea, creatinine, alanine transaminase (ALT), aspartate transaminase (AST), bilirubin, alkaline phosphatase (ALP) and protein were investigated in alloxan-induced diabetic rats.Results: No acute toxicity were observed in the rats after administration of the plant extract up to a dose of 2000 mg/kg. The effect of the extract on glucose tolerance test was significant from 30 to 180 min after treatment. In the diabetic rats, the extract showed significant (p < 0.05) anti-hyperglycemic activity at 400 mg/kg. It also led to significant increases in body weight and HDL-cholesterol, and significant reductions in serum LDL, triglycerides and transaminases (p < 0.05).Conclusion: These results indicate that the aerial parts of G. tricornutum possess significant antidiabetic potential.Keywords: Diabetes, Galium tricornutum, Glibenclamide, Glucose tolerance tes, Lipid profil

A space-time pseudospectral discretization method for solving diffusion optimal control problems with two-sided fractional derivatives

We propose a direct numerical method for the solution of an optimal control problem governed by a two-side space-fractional diffusion equation. The presented method contains two main steps. In the first step, the space variable is discretized by using the Jacobi-Gauss pseudospectral discretization and, in this way, the original problem is transformed into a classical integer-order optimal control problem. The main challenge, which we faced in this step, is to derive the left and right fractional differentiation matrices. In this respect, novel techniques for derivation of these matrices are presented. In the second step, the Legendre-Gauss-Radau pseudospectral method is employed. With these two steps, the original problem is converted into a convex quadratic optimization problem, which can be solved efficiently by available methods. Our approach can be easily implemented and extended to cover fractional optimal control problems with state constraints. Five test examples are provided to demonstrate the efficiency and validity of the presented method. The results show that our method reaches the solutions with good accuracy and a low CPU time.Comment: This is a preprint of a paper whose final and definite form is with 'Journal of Vibration and Control', available from [http://journals.sagepub.com/home/jvc]. Submitted 02-June-2018; Revised 03-Sept-2018; Accepted 12-Oct-201

Statistical analysis of the effect of machining parameters on fatigue life of aerospace grade aluminum alloy (AL 6082T6)

In this research work, aerospace grade aluminium alloy (Al 6082-T6) was analysed for the effect of cutting parameters on the fatigue life of the machined samples and optimization of cutting parameters for response factor. Different combinations of machining parameters were selected according to the ISO 3685 for sample preparation. Fatigue life of the samples was the response variable under investigation. Specimens for the rotating bending fatigue test were prepared according to the BS ISO 1143:2010 standards. The cutting inserts were selected from Sandvik Coromant catalogue recommended for machining of Al 6082-T6 alloy. A Designed of Experiment (DoE) with full factorial design was employed and a total of 81 experiments were performed for combination of cutting parameters. Fatigue life of the samples was observed to decreases with increasing feed rate, which is attributed to the compressive residual stresses at the surface of the samples. However, fatigue life increased with higher cutting speed and Depth of Cut (DoC)

A model for power efficiency of mobile devices through lightweight method level computational offloading

Mobile devices have become an integral part of our daily lives. However, the restricted battery timing curtails longer operational hours. To tackle the limited battery timing issue, a technique, computational offloading is used. In computational offloading, the intensive tasks are offloaded from mobile devices to remote server in order to execute the task remotely and save battery life. Computational offloading frameworks/models based on VM migration, whole application migration, or traditional method level offloading are resources intensive and time consuming. The dynamic partitioning of application, execution of task at cloud server, service call by Simple Object Access Protocol (SOAP) and no defined mechanism for predefined parameters, make the previous method level computational frameworks/models inefficient for energy saving. In order to address the inefficiencies of previous method level computational offloading frameworks/models, a lightweight method level computational offloading model is proposed. Four distinct components are deployed in the proposed model which eliminates the shortcomings of previously developed frameworks/models. A Representational State Transfer (REST) based technique developed for calling the remote services which is based on JSON instead of XML, and hence is lightweight. REST also reduces the size of communication data at approximately 100% as compared to SAOP service call. Surrogate server is configured at a single hop distance which reduces the RTT and ultimately reduces the power consumption. The application is partitioned at method level by a novel dynamic technique in source code, which counters the inefficiencies of existing partitioning techniques. A mechanism for selection of predefined parameters is defined. These parameters are important to consider before each offload. The predefined parameters consist of battery level, network type, and execution time which affirms the energy saving during offloading. The proposed framework is implemented in the real mobile cloud computing environment. Execution time and energy consumption of both local execution and traditional offloading are benchmarked in order to investigate and validate the performance of the proposed lightweight method level model. The prototype is developed with three components which are REST-Offload, Local Execution and Traditional- Offload and then tested in real mobile cloud environment for Execution Time and Energy Consumption. The result of this research indicates that the proposed solution diminishes resources utilization. The REST-Offload is significantly useful compared to both Local Execution and Traditional Offloading methods. It reduces about 50% Execution Time and approximately 38% Energy Consumption