Variety Of Analytical Instruments Research Articles

Proposed Digital Marketing Strategy to Increase Customer Acquisition for Travel Agent Company

This study is a comprehensive examination designed to explore a number of complex challenges encountered by PT Selaras Citanusa (Selaras Wisata) in their endeavor to attract consumers organically, particularly within the context of the thriving Umrah tourism industry. The COVID-19 pandemic has posed significant difficulties for this enterprise. Efforts to increase market share and increase public awareness of brands on the market represent one of the greatest obstacles. This study presents a comprehensive qualitative methodology that combines several resilient analytic techniques. The 7Ps marketing mix method is used to describe the essential components of Selaras Wisata’s marketing strategy. Fishbone analysis is used to identify the fundamental causes of the business’s numerous problems. The SWOT analysis aides in evaluating the company’s environmental strengths, vulnerabilities, opportunities, and threats. In addition, content analysis is used to perceive and measure the impact of the company’s numerous marketing efforts. The study also includes a comprehensive examination of the external factors influencing Selaras Wisata. By employing Porter’s Five Forces analysis, the research investigates the industry’s structure and other external factors that may impact the company. Selaras Wisata uses customer behavior analysis to obtain a deeper understanding of customer preferences, requirements, and levels of satisfaction with the services provided. The data underlying this study are collected through in-depth interviews with PT Selaras’s internal team members. This information is then thoroughly analyzed using a variety of analytical instruments, such as SWOT analysis and Fishbone analysis. The author anticipate that the outcomes of this research will provide valuable contributions to Selaras Wisata’s efforts in crafting an effective digital marketing strategy to enhance customer engagement and ultimately improve public perception.

Direct Carbonization of Tobacco Straw Cores to Prepare Porous Carbon for Supercapacitor Applications

A large amount of tobacco straw residues is produced around the world every year. These tobacco straw residues are usually incinerated or landfilled directly, which cause environmental pollution and waste of resources. Therefore, it is necessary to find a green way to recycle these tobacco straw residues. Converting tobacco straw residues into biomass carbon materials for supercapacitor electrode materials is an appropriate way. In this study, tobacco straw core carbon (TSC) was obtained from tobacco straw core waste, which was carbonized directly in the tube furnace without N2. The tobacco straw core carbon had a higher specific surface area because of the self-activation of the H2O and CO2 in the carbonization. A variety of analytical instruments were used to characterize the prepared porous carbon. Herein, this work can provide new ideas for energy materials, and solve the problem of the disposal of tobacco straw residues. What’s more, it also can provide a sustainable development opportunity for tobacco farmers to alleviate poverty, dig potential and transform.

Chemometric Evaluation of Repeatability Using the Autocorrelation Method in High-Performance Liquid Chromatography with Ultraviolet Detection.

The mixed random processes of the first order autoregressive process (AR(1)) and white noise have been proved to provide a good approximation of baseline noise in a variety of analytical instruments, and may therefore be useful for estimating precision profiles. This study aims to examine a recently proposed autocorrelation method for estimating three noise parameters involved in the mixed processes (two for AR(1) and one for white noise) of HPLC, which can then be used to calculate the precision profile. This chemometric method was applied to repeatability evaluations of estriol determination using HPLC with UV detection (HPLC-UV). The relative standard deviations (RSDs) of peak area measurements for 5.0 mg/L estriol were observed to be 1.42% for the autocorrelation method and 1.63% for actual repeated measurements of real samples (n = 6). The theoretical RSDs of the autocorrelation method fell within the 95% confidence intervals of the repeated measurements. It is found that the noise parameters are obtained from real chromatographic baseline via the autocorrelation method. Moreover, the instrumental detection limit of estriol based on ISO 11843 was obtained from the precision profile (plot of RSD of measurements against concentration). This is the first paper to describe the autocorrelation method is a practically useful technique for evaluating the precision profile of HPLC-UV analyses without recourse to the repeated measurements of real samples.

Application of Dispersive Liquid-Liquid Microextraction in Forensic Toxicological Analysis.

Currently, the main sample pretreatment methods for forensic toxic analysis are liquid-liquid extraction （LLE） and solid-phase extraction （SPE）. As a simple, convenient, and low-cost LLE method, dispersion liquid-liquid microextraction （DLLME） has high enrichment factor and good extraction efficiency, and therefore has attracted the attention of many researchers in the field of toxicology analysis in recent years. As a multi-functional microextraction method, DLLME has been widely used in the analysis of pesticides, sleeping sedatives, drugs and heavy metal poisons in forensic toxic analysis. Meanwhile, it can also be used in combination with such a variety of analytical instruments as gas chromatography-electron capture detectors （GC-ECD）, high performance liquid chromatography-diode array detectors （HPLC-DAD）. As a sample pretreatment method, DLLME has the advantages of simple operation, less use of organic solvent, reliable results and good reproducibility, thus can meet the requirements of modern court toxic analysis.

Effect of molecular-scale surface energy alteration of aluminium on its corrosion resistance behaviour

The degree of available energy on a surface determines how a surface interacts with its surrounding environment such as corrosion. Current approaches to protection of Aluminum surfaces from corrosion mainly focus on adding an organic or inorganic layer to either act as a barrier from oxidant or scarifying to inhibit the corrosion. Altering the surface energy of Al on a molecular level is another alternative approach to efficiently modify the Al surface without the need for another thick expensive protective or scarifying materials. Herein, an attempt was made to understand how a molecular scale energy alteration improves the anticorrosion behavior of an aluminum surface. Two different surface engineering alteration strategies have been discussed; termed ALOSH and ALTSH modification. A variety of analytical instruments, i.e., FTIR, EDAX, XPS, SEM, AFM, WCA, and SFE measurement were used to systematically characterize the samples. Electrochemical impedance spectroscopy revealed that there are different resistances after the surface modifications. The trapping air resistance appeared in ALTSH is approximately 2.4 and 36 times higher than that of ALOSH and bare samples, respectively. The potentiostat analysis results showed that the mili inch per year value of coating for ALTSH was 0.012 while that of ALOSH was 0.507. It was also found that the low surface energy alteration without using inert molecules is not enough to render corrosion inhibition property, as it needs to have a protective energy barrier with no or minimal active electrochemical behavior.

A model system to mimic environmentally active surface film roughness and hydrophobicity

This work presents the development and initial assessment of a laboratory platform to allow quantitative studies on model urban films. The platform consists of stearic acid and eicosane mixtures that are solution deposited from hexanes onto smooth, solid substrates. We show that this model has distinctive capabilities to better mimic a naturally occurring film's morphology and hydrophobicity, two important parameters that have not previously been incorporated into model film systems. The physical and chemical properties of the model films are assessed using a variety of analytical instruments. The film thickness and roughness are probed via atomic force microscopy while the film composition, wettability, and water uptake are analyzed by Fourier transform infrared spectroscopy, contact angle goniometry, and quartz crystal microbalance, respectively. Simulated environmental maturation is achieved by exposing the film to regulated amounts of UV/ozone. Ultimately, oxidation of the film is monitored by the analytical techniques mentioned above and proceeds as expected to produce a utile model film system. Including variable roughness and tunable surface coverage results in several key advantages over prior model systems, and will more accurately represent native urban film behavior.

Study of Pb²⁺, Cd²⁺ and Ni²⁺ adsorption onto activated carbons prepared from glycyrrhiza residue by KOH or H₃PO₄activation.

The activated carbons (ACs) were prepared from glycyrrhiza residue by KOH or H₃PO₄activation and were used for removing Pb²⁺, Cd²⁺ and Ni²⁺ from simulated wastewater. The changes of the physical structure and chemical properties of the glycyrrhiza residue before and after activation were characterized by using a variety of analytical instruments and methods. Kinetics and equilibrium isotherms were obtained and the effects of solution pH value and adsorbent dosage were studied in batch experiments. The results indicated that after activation, the surface structure of glycyrrhiza residue changes and surface area, micropore volume also increase accordingly. Kinetic studies showed that the adsorption followed a pseudo-second-order reaction. The Freundlich model fitted the equilibrium data better than the Langmuir isotherm. According to the Langmuir equation, the maximum adsorption capacities of ACs prepared from glycyrrhiza residue by KOH and H₃PO₄activation for Pb²⁺, Cd²⁺ and Ni²⁺ are 2.170 mmol/g, 2.617 mmol/g, 3.741 mmol/g and 2.654 mmol/g, 3.095 mmol/g, 3.076 mmol/g, respectively, which are much higher than ACs prepared from other raw materials.

Kinetic rate-limiting steps in dehydrogenation of Li–N–H and Li–Mg–N–H systems – Effects of elemental Si and Al

The study is focused on the (LiNH 2 + LiH) and the (2LiNH 2 + MgH 2) hydrogen storage systems. Efforts were made to achieve an in-depth understanding of the dehydrogenation mechanisms following the introduction of elemental Si and Al to both systems. A variety of analytical instruments were employed, such as Temperature-Programmed Desorption, Mass Spectrometry, X-ray diffraction (XRD) and InfraRed spectroscopy. Unlike the effect of elemental Al in the (LiNH 2 + LiH) system, which showed no promising improvement in the dehydrogenation, a significant kinetic improvement in the (LiNH 2 + LiH) system was achieved upon addition of elemental Si. Kinetic improvement by elemental Si was described as a result of the LiH destabilisation through the formation of a Li 2Si phase and an increase in H − anion concentration. On the other hand, once elemental Al is added to the (2LiNH 2 + MgH 2) system, the overall dehydrogenation kinetics of the system is delayed through the formation of a LiAl Phase. The results suggest that dehydrogenation mechanism in both the (LiNH 2 + LiH) and the (2LiNH 2 + MgH 2) systems are identical. Dehydrogenation reaction starts with the electrostatic interaction of the oppositely charged hydrogen atoms in amide and hydride and proceeds by mass transfer of reactant species across the product layer at the later stage of the dehydrogenation. However, it was particularly identified that each system has a unique kinetic rate limiting step. Dehydrogenation kinetics seems to be controlled by the diffusion of the H − anion in the (LiNH 2 + LiH) system but by the diffusion of the Li + cation in the (2LiNH 2 + MgH 2) system.

A Continuous-Flow Gas Chromatography 14C Accelerator Mass Spectrometry System

Gas-accepting ion sources for radiocarbon accelerator mass spectrometry (AMS) have permitted the direct analysis of CO2 gas, eliminating the need to graphitize samples. As a result, a variety of analytical instruments can be interfaced to an AMS system, processing time is decreased, and smaller samples can be analyzed (albeit with lower precision). We have coupled a gas chromatograph to a compact 14C AMS system fitted with a microwave ion source for real-time compound-specific 14C analysis. As an initial test of the system, we have analyzed a sample of fatty acid methyl esters and biodiesel. Peak shape and memory was better then existing systems fitted with a hybrid ion source while precision was comparable. 14C/12C ratios of individual components at natural abundance levels were consistent with those determined by conventional methods. Continuing refinements to the ion source are expected to improve the performance and scope of the instrument.

Synthesis of Nanostructured Silicon Carbide through an Integrated Mechanical and Thermal Activation Process

Changes of crystal structures and microstructures of SiO2 and graphite powder mixtures induced by high‐energy milling, the effect of these changes on the reactivity of reactants, and the mechanism of enhanced SiC formation have been studied using a variety of analytical instruments, including X‐ray diffractometry, scanning electron microscopy, transmission electron microscopy, solid‐state 29Si nuclear magnetic resonance, and nitrogen adsorption (i.e., the BET method). High‐energy milling before carbothermic reduction leads to substantial changes in the structural and energy states of the reactants, which in turn increases the reactivity of the reactants and enhances the formation of nanostructured SiC particles. Furthermore, the structural and energy‐state changes contribute to the enhanced SiC formation through the increased reaction kinetics as well as the increased reaction driving force.

Role of Modern Analytical Chemistry in Material Analyses for Trace Metals

AbstractThe trend in the modern analytical laboratory is toward lower and lower analytical concentration measurements. The analyst has a variety of analytical instruments and techniques in which to meet the ever growing need for lower concentration measurements with improved precision and accuracy. Techniques available to the analyst include flame and electrothermal atomization‐atomic absorption spectrometry, inductively coupled plasma atomic emission spectrometry, inductively coupled plasma/mass spectrometry, laser enhanced ionization spectrometry, neutron activation analysis, spectrophotometry, isotope dilution mass spectrometry, X‐ray fluorescence spectometry, electroanalytical, and chromatography. However, there is no analytical technique that is a panacea for all analytes in the modern analytical laboratory. Steps the analyst must consider to obtain the highest degree of precision and accuracy include the obtaining of a representative sample, the selection of the “best” analytical method, the preparation of the sample, the calibration of the instrumentation, the deciding on the level of effort for the chemical measurement and the evaluation of the data are discussed.

INSTRUMENTATION IN TOXICOLOGY: ASSESSING TOXIC MATERIALS AND PRODUCTS IN THE BODY*

AbstractSome examples of potentially toxic materials occurring in occupational or general environmental situations are given in table 1 to illustrate the magnitude of the toxicological assessment problem on which current health protection is based. The field of drugs, especially the narcotics and hallucinogens, is another area of toxicology that has assumed recent importance.The specific requirements in assessing toxic materials and their breakdown products in the body are: (a) to establish the concentration levels and to follow the course of the metabolism. (b) to identify target organs and measure functional changes or tissue damage in the target organs.Important advances in the knowledge needed to meet these two requirements have been made possible by the technical ingenuity of instrument designers. Some instruments are available that permit aspects of toxicological assessment to be realized on intact body organs. Where this ideal methodology is not possible, blood samples may be drawn and small samples of tissue from selected organs may be secured by needle biopsy without harming the individuals. This material may be examined histologically by microscopy, and chemically with a variety of analytical instruments. Then there are the main body effluents—urine, feces, and exhaled air, which can also be examined in a variety of ways.