Scientific Research and Essays

  • Analysis of Solvent Effect on Formation Constants and Speciation of Cobalt(II), Copper(II) and Lead(II) Complexes of L-Methionine and Uracil

    The analysis of coordination of chelating agents to metal ions in the formation of complexes under different experimental conditions provide information on the effects of the conditions on the extent of the coordination of the ligands to the metal ions for potential applications in bioinorganic and environmental Inorganic Chemistry. The effect of solvent on the coordination of L-methionine (primary ligand) and uracil (secondary ligand) to Co(II), Cu(II) and Pb(II) ions in the formation of binary and ternary complexes have been potentiometrically investigated in water and 40% (v/v) ethanol- water media at 27 °C and ionic strength of 0.02 mol dm–3was maintained by using NaNO3. The proton-ligand stability constants and formation constants of the binary and ternary systems were established under the experimental conditions. The formation constants of the ternary complexes were numerically compared with the corresponding binary complexes in terms of Δ log K and percentage relative stabilization (%RS). Speciation of the metal ions, binary and ternary complexes as a function of pH in the solutions was investigated by using HYSS program. The ligands were observed to form more stable ternary complexes than binary complexes. The proton-ligand stability constants the ligands and the formation constants of the metal complexes were found to be higher in 40% (v/v) ethanol-water than water. The distribution of the species revealed a decrease in the metal ion concentrations with increase in the concentrations of the binary and ternary as pH increased. The chelating agents interacted strongly with the metal ions and showed different selectivity towards the metals ions. These properties can be exploited in combating metal poisoning, separating the metals and expounding the bioinorganic chemistry of the metal ions and the ligands.


    Introduction: Burnout Syndrome is conceptualized as a result of chronic stress in the workplace, characterized as a psychological syndrome composed of emotional exhaustion, depersonalization and reduced personal fulfillment. The prevalence of this syndrome in medical students is quite expressive, and the more the student is exposed to the academic cycle, the greater the risk of developing an anxiety disorder, especially Burnout Syndrome. Objectives: To analyze in the literature the correlation between Anxiety Disorders, Burnout Syndrome and Medical Students. Methodology: The research took place in the CAPES, PubMed and VHL Regional Portal. The terms “burnout”, “anxiety disorders” and “medical students” were considered as descriptors. Articles published between 2014 and 2019 were included. Results: Of the 69 articles found, only six were included in the review. Evidence was found that there is an association relationship between medical study and student mental exhaustion. It was also relating the time of exposure to the course with a higher prevalence of mental disorders. Relaxation techniques have shown a decline in Burnout’s cognitive and emotional stress and anxiety. Conclusion: Burnout Syndrome is a reality among medical students. However, despite the importance of the theme, the literature on this correlation is incipient. There is a need for further investigations into strategies that aim to reduce the incidence, and consequently the prevalence of this syndrome, favoring the mental health of college students and the training of good health professionals.

  • Maintenance of Bullet Train Based on Mathematical Planning and Workshop Scheduling

    Nowadays, bullet train service stations often suffer from the phenomenon of low operating efficiency due to the unreasonable arrangement of bullet trains that stay in service stations for too long. In order to solve this problem, based on the information of bullet train arrival in two periods of a bullet train service station, this paper comprehensively considered the input source, queuing rules and overhaul intensity of the train service system, determined the objective function and multiple constraint conditions, and established the 0-1 programming model and Uncorrelated Parallel Machine Optimization Model. The model established in this paper can relieve the load pressure of bullet train service station to a great extent, improve the operation efficiency of the service station under the condition of ensuring the maintenance quality of bullet train, and provide theoretical basis for realizing the shortest maintenance time of bullet train service station.


    Introduction Benzodiazepines (BZD) are drugs that act directly on the central nervous system, altering cognitive and psychomotor aspects. In Brazil, it is the third class of most prescribed drugs, being used by approximately 4% of the population. The restricted, rational and short-term use of benzodiazepines is not observed on a large scale by professionals who attend the Ipaumirim Family Health Strategy, due to the high number of people who just want the revenue renewal. General Objective: To develop an action plan to promote the reduction of drug abuse controlled by users of the Ipaumirim Family Health Strategy – CE. Methodology: This is an intervention project that consists of an action proposal to face a real problem. The interventions were performed at the Basic Health Unit of Ipaumirim – CE, from June 18 to August 16, 2018 with evaluation every three months, with 36 users. Identification was performed through medical records, interviews in routine consultations. Results: the lack of information from users was clear, resulting in changes in actions involving primary care to alternative treatments such as physical activity, food reeducation and psychotherapy, stimulating actions such as the booklet, an organizational basis, since it does not have the horus system. Conclusion: the study effectively allowed the development of a new health promotion strategy.

  • Experimental Study on the Performance of on-site Mixed Emulsion Explosives and Rock Impedance Matching

    The proportion of on-site mixed emulsion explosives in mining is getting higher and higher, in order to better use the explosive performance of mixed explosives to improve energy utilization. Based on the wave impedance theory, the wave impedance of mixed explosives is changed to make rocks The wave impedances are matched to achieve the purpose of improving the blasting effect and reducing the bulk rate. After field test, increasing the sensitizer content within a certain range is beneficial to the improvement of explosive performance. When the explosive sensitizer content is 1.15%, the best matching coefficient of mixed explosive and rock impedance is 2.51, the rock after blasting is large. The block rate is reduced and the rock crushing effect is better. After this matching test, it is shown that it is feasible to improve the blasting performance by adjusting the explosive performance of the explosive by the optimal wave impedance coefficient according to the hardness of the rock, which can provide reference for the peers.

  • Numerical simulation of propeller jet field based on Star-ccm+

    During the ship’s voyage, the propeller jet affects the movement of silt at the bottom of the bed. To research the influence of the bottom boundary on the propeller jet field, this paper takes the standard propeller DTRC4119 propeller as the research object and uses the CFD software Star-ccm+ to carry out a numerical simulation of the propeller jet under uniform flow. The flow velocity distribution of the jet under four operating conditions is mainly analyzed, including the axial velocity, tangential velocity and radial velocity of the jet. The results show that the distance between the propeller and the boundary does not affect the magnitude and distribution of the velocity on the initial plane but affects the shape of the axial velocity and the velocity on the central axis in the development zone; The closer to the bottom boundary, the greater the disturbance of tangential velocity and radial velocity, the peak value of tangential velocity will be affected and changed from central symmetry of velocity to unanimous trend earlier. The radial velocity contributes less to the overall velocity and can be ignored

  • Development of a workpiece transfer machine based on a gas-electric hybrid system

    To solve the problem of transferring the workpiece to the next process, design a gas-electric hybrid workpiece transfer machine. The mechanical structure of workpiece transfer in automatic production line is discussed. The transfer of workpiece can be realized by pulse motor, pneumatic system is used to clamp and lift the workpiece,and design this system, analyze the principle of pneumatic system and design the PLC circuit. The results show that the designed device has the characteristics of simple structure, operability and practicability.

  • Finding Waldo: Two Routes for Processing Visual Search in Complex Scenic Images

    This paper reviews the cognitive mechanisms underlying visual search in complex visual images. Visual search is a type of task that we are constantly engaged in our everyday lives. Here, the current paper introduces the current literature that suggests that there are two different processing routes that support visual search in human observers: Bottom-up and Top-down processing. Bottom-up processing allows the visual system to process the sensory information from the visual image as it is, whereas top-down processing guides the visual system to efficiently allocate attention to a part of the image to facilitate the search process. The two processing routes via bottom-up and top-down processing work in concert during complex visual search, guiding our search behavior to be more efficient and adaptive. In closing remark, this review also briefly discusses how the current knowledge about the roles of bottom-up and top-down processing in visual search can contribute to development of computer vision and artificial intelligent.

  • Influence of Elements of Work Realities on HRD Mandate Capability in Banking Organisations in Nairobi County, Kenya

    Globally, business organizations recognize that engaging human resource management practices on an international standard is imperative. But realizing target performance from just scarce resources is a challenge to most organisations. Many organisations are continuously spending time trying to control and master change making them losers. With the current practice, HR has not been able to deliver on training line management in methods of achieving high employee production. This paper investigated the Influence of Elements of Work Realities on HRD Mandate Capability in Banking Organisations in Nairobi County, Kenya. The main objectives pursued included to establish the relationship between employer-employee champion and HRD mandate capability in Banking Organisations in Nairobi County, Kenya; to determine the association between continuous transformation agent and HRD mandate capability in Banking Organisations in Nairobi County, Kenya. A survey of banking institutions was used while a questionnaire and interview schedule and content analysis were used to gather primary data. The target population was 850 and a sample size of 272 was used. Statistical analysis was done using Statistical Package of Social Sciences (SPSS) current version. The findings confirmed that there are problems facing human resource mandate delivery capability. It was concluded that all the two elements of work realities have significant influence on HR mandate delivery capability. It was therefore recommended that organisations need to consider factors such as employer-employee champion and continuous transformation agent elements which are capable of influencing HR mandate delivery capability. Human resource should therefore discontinue their non-value adding traditional practices to service delivery.


    The paper discusses a unique technique developed initially at Nation Institute of Technology, Surat that is remodeled in real world applications. The concept consists primarily of a user-friendly software facilitating direct communication with any intelligent or learning system/robot operating under known parameters of motor specifications. Any software base permitting high level PC interface without ASCII interrupt can be used and here Visual Basic is represented for easy programing. This allow for a learning operation mode where a prevention of time lag implementation stores machine data based on movements by the machine stored or actions taught. Such learning aspects make the machine more efficient where the robot can either perform individual actions as needed or learn new methods for the same results and can perform a series of actions continuously. Using the stored data, the machine is also capable of autonomous movements based on the path of least resistance as calculated by the time it takes to perform an act. Unlike the ALPHA model, new and improved model is tested on a CNC 6 axis manufacturing machine This paper focuses on methodology of interface through VB programing and does not contain associated files to retain any possible patent applications.