Chemical Safety Concerns of Sulfur Mustard Analog, 2-Chloroethyl Ethyl Sulfide, in Laboratory Study

: Sulfur mustard (SM), a classic chemical weapon in the vesicant category, can induce severe damage, for which the therapy is still limited even today. Laboratory work is essential in unveiling toxicological effects and developing medical countermeasures. Sulfur mustard analog 2-chloroethyl ethyl sulfide (CEES), is employed in the lab for less toxicity. However, due to its similar characteristics to SM (being oily, hydrophobic, and volatile), the manipulation of CEES still needs special attention to avoid personnel injury and laboratory pollution. Here, to clear the chemical safety concerns in the laboratory study of CEES, the working procedure and experimental data are summarized, which might help educate new researchers to be skilled and professional.

An Ergonomic Analysis on Working Postures of Construction Site Workers

Risk factors related to work activity and ergonomics can enhance the probability that some persons may develop a MSD (musculoskeletal disorder). Usually the MSD develops due to high task repetition, forceful exertion, and repetitive/sustained awkward postures. MSD is also found in some cases where workers are engaged with working in awkward postures, cold temperatures, contact stress, heavy load, static postures, and vibration, etc. Many studies explain the problems for MSD, but in this chapter an effort is taken to rank the maximum body movement and body parts as per the different types of work flow system such that ergonomics design can be planned. Physical disorders can be avoided by finding and ranking the difficult task and the affected body part due to that kind of work. The prioritization of task will help the organization to think of sustainable designs of working procedure or instruments or machines to provide maximum comfort to humankind. It may also help to frame policies for occupational safety and hazards in workplace.

Human Face Detection Techniques: A Comprehensive Review and Future Research Directions

Face detection, which is an effortless task for humans, is complex to perform on machines. The recent veer proliferation of computational resources is paving the way for frantic advancement of face detection technology. Many astutely developed algorithms have been proposed to detect faces. However, there is little attention paid in making a comprehensive survey of the available algorithms. This paper aims at providing fourfold discussions on face detection algorithms. First, we explore a wide variety of the available face detection algorithms in five steps, including history, working procedure, advantages, limitations, and use in other fields alongside face detection. Secondly, we include a comparative evaluation among different algorithms in each single method. Thirdly, we provide detailed comparisons among the algorithms epitomized to have an all-inclusive outlook. Lastly, we conclude this study with several promising research directions to pursue. Earlier survey papers on face detection algorithms are limited to just technical details and popularly used algorithms. In our study, however, we cover detailed technical explanations of face detection algorithms and various recent sub-branches of the neural network. We present detailed comparisons among the algorithms in all-inclusive and under sub-branches. We provide the strengths and limitations of these algorithms and a novel literature survey that includes their use besides face detection.

Physical model of noise in the combustion chamber of a liquid-propellant engine

В статье рассмотрена задача определения резонансных характеристик камер сгорания жидкостного ракетного двигателя. Приведён и математически обоснован подход к созданию алгоритмов решения такой задачи с помощью анализа спектральной плотности мощности шумовых сигналов параметров рабочих процессов. Рассмотрены вычислительные эксперименты и продемонстрированы их результаты для модельного сигнала с единственной модой. In this article a task of determining of resonance characteristics for combustion chambers of a liquid rocket engine. The approach for development of algorithms to solve this task using analysis of power spectral density of noise signals of working procedure parameters is considered and mathematically justified. Computational experiments are considered and their results for a model signal with a single mode is demonstrated.

Use of Taguchi Methods for Hierarchy of Influence Factors in the Application of Carbonitration in a Fluidized Bed Steel for 41Cr4 Steel

The work is based on carbonitriding in a fluidized layer with methane and ammonia gas applied to 41Cr4 steel samples. To achieve the best possible results, other factors must be taken into account, than those specific to carbonitring. It was necessary to use a partially factorial working procedure due to the increase in the number of factors. An A18 matrix has been used, with 18 lines of experiments in which three levels have been modified for 6 factors. The objective function was fixed at the final hardness after carbonitriding, hardening and tempering. The carbonitriding was performed in fluidized bed with granular solid ground and sorted to 0.1- to 0.16mm, and brought to fluidization with a mixture of methane and ammonia. The hardening has been done directly after carbonitriding in the fluidized bed. The experiments have been performed according to Taguchi Methods and the results indicate an optimal regime and the influence of the factors considered on the hardness after the thermo-chemical treatment and the thermal treatment. Metallographic analysis has been performed on the carbonitrided layer.

Scaling of Rain Attenuation Models: A Survey

The scaling of rain attenuation methods is promising to quickly estimate power degradation in radio links due to rain with known findings from previous measurements. Although the frequency scaling of rain attenuation technique was introduced ages ago, it has not been addressed adequately. Furthermore, some emerging scaling techniques have recently been proposed in the literature through polarization, elevation angle, and pathlength parameters. A survey paper might play a vital role in order to comprehend all these study areas systematically. However, a survey paper on this research field is currently unavailable in the literature. This review categorizes all the research works using the inherent properties of scaling techniques. Furthermore, this study presents a comparative investigation of parameter-based scaling techniques by considering their working procedure, applicable frequency ranges, and innovative ideas incorporated with all of these models.

Design and Realization of Recovery System of Chang’e-5 Reentry Spacecraft

On December 17, 2020, the Chang’e-5 reentry spacecraft landed safely and brought back the lunar sample without damage. This paper describes the recovery system that has critically contributed to the scientific success of the Chang’e-5 missions and presents the technical requirements and constraints of the recovery system for the Chang’e-5 reentry spacecraft and discusses the design process of the recovery system, including the system composition, working procedure, and some other key aspects. Finally, the ground cover rejection tests and air drop and flight tests were carried out to confirm the design configuration. The results showed that the Chang’e-5 reentry spacecraft recovery system was designed correctly, and its functions and performances met the design requirements. A breakthrough in the recovery technology of the reentry spacecraft was achieved for Chinese first lunar sample-return mission.

Assessment of Job Risks in the Chemical Laboratory of the Pharmacy Study Program with Job Safety Analysis (JSA) Techniques

Chemistry laboratory organizes practicum, one of them quantitative pharmaceutical chemistry which uses a variety of chemicals and tools where if not careful, not following instructions or procedures even underestimate will cause work accidents and/ or occupational illness. Is observational descriptive research on the job risk assessments in chemical laboratories prodi pharmacy with JSA techniques aimed at finding out the risk of work performed. Population is type practicum work in chemistry laboratory and the sample is quantitative pharmaceutical chemistry practicum. Data collection techniques i.e. the work that has been selected is further determined with the working procedure and the working steps and then determines the findings of errors from each step of the work then further identify the potential hazards of each step of the work. Data analysis techniques is data from each finding of errors determined potential injury / danger / loss and its impact is then calculated risk value (risk matrix) i.e. the value of consequences multiplied by opportunity value where the results are could grouped into risk extreme, high, medium or low that continued with to determine safeguards measures that can be done to control the such danger. The results showed that performs the titration step has high very risk level value compared to another work step other of pharmaceutical chemical practicum quantitative. Titration activities carry an extreme or significant risk of harm when performed incompatible with working measures and unsafe with potential danger (disadvantage) is liquid evaporates (inhaled), disturbances The End Point of the Titration: change in color and determination of concentration, and perform movements manual repetitive continuously namely mixing the liquid or rotating the container (erlenmeyer) contains a chemical liquid by hand continuously. Chemistry laboratory organizes practicum, one of them quantitative pharmaceutical chemistry which uses a variety of chemicals and tools where if not careful, not following instructions or procedures even underestimate will cause work accidents and/ or occupational illness. Is observational descriptive research on the job risk assessments in chemical laboratories prodi pharmacy with JSA techniques aimed at finding out the risk of work performed. Population is type practicum work in chemistry laboratory and the sample is quantitative pharmaceutical chemistry practicum. Data collection techniques i.e. the work that has been selected is further determined with the working procedure and the working steps and then determines the findings of errors from each step of the work then further identify the potential hazards of each step of the work. Data analysis techniques is data from each finding of errors determined potential injury / danger / loss and its impact is then calculated risk value (risk matrix) i.e. the value of consequences multiplied by opportunity value where the results are could grouped into risk extreme, high, medium or low that continued with to determine safeguards measures that can be done to control the such danger. The results showed that performs the titration step has high very risk level value compared to another work step other of pharmaceutical chemical practicum quantitative. Titration activities carry an extreme or significant risk of harm when performed incompatible with working measures and unsafe with potential danger (disadvantage) is liquid evaporates (inhaled), disturbances The End Point of the Titration: change in color and determination of concentration, and perform movements manual repetitive continuously namely mixing the liquid or rotating the container (erlenmeyer) contains a chemical liquid by hand continuously.

Image Analysis for Spectroscopic Elemental Dot Maps: P, Al, and Ca Associations in Water Treatment Residuals as a Case Study

The associations of elements upon a heterogeneous surface may control nutrients or pollutants sorption and release, having agricultural and environmental implications. This chemical behavior can be elucidated by spatial spectroscopy, followed by image analysis. The purpose of this paper is to present a working procedure for image analysis using the free program ImageJ that can be applied for dot maps of three or more elements produced by solid-state spectroscopy. Detailed step-by-step instructions lead to visual and quantitative information regarding elements associations. The working procedure was demonstrated for P, Al and Ca dot maps produced by scanning electron microscopy energy dispersive spectroscopy (SEM-EDS) for surfaces of Al-based water treatment residuals (Al-WTRs), a by-product of drinking water pretreatment with alum coagulant. Al-WTR was reused to adsorb the macro-nutrient P from polluted soil leach and dairy wastewater (WW). Surficial P onto Al-WTR, SL-Al/O-WTR, and WW-Al/O-WTR (0.56, 0.93, and 2.15%, respectively) displayed sorption dynamics, mostly with Al and Ca. Quantification of the spatial proportions of individual elements and their associations indicated P-Al pool > P-Ca pool (45–24% and 17–7%, respectively). Upon introducing P-rich dairy wastewater, the behavior of P sorption by Al and Ca changed and became more clustered. A ternary phase of P-Al-Ca covered 38% of the area with signal, compared to 4.3 and 4.6% of the area in Al-WTR and SL-Al-WTR, where it was limited to particles edges only. Thus, the presented protocol may promote employing image analysis for geochemical applications, elucidating chemical behavior and affinities. Advantages and pitfalls are discussed.