Influence Of Environmental Pressures Research Articles

Thermal Safety Study of Emulsion Explosive Matrix under the Coupled Effects of Environmental Pressure and Bubble Content with Internal Heat Source

Emulsion explosives have become a hot topic in various studies due to their explosive combustion characteristics and detonation performance under different environmental pressures. The thermal safety of an emulsified matrix was studied with ignition energy as the characterization. A minimum ignition energy test experimental system for emulsion matrices was established in this research. The system simulated the occurrence of hot spots inside emulsion matrices using an electric heating wire. The effect of bubbles on the thermal safety of the emulsified matrix was studied by adding expanded perlite additive to the emulsified matrix. This study investigated the variation trend in the minimum ignition energy of the emulsion matrix under the coupled effect of bubbles and ambient pressure using the orthogonal experimental method. The impacts of two factors on the thermal safety of the emulsion matrix were studied at different hot-spot temperatures. Coupled analysis experiments were conducted on emulsion matrices containing 0%, 1.5%, and 3% expanded perlite under pressure environments of 1 atm, 2 atm, and 3 atm. The critical hot-spot temperature of the emulsion matrix significantly decreases with increasing bubble content at 1 atm and 2 atm pressures, as revealed by intuitive analysis and analysis of variance. However, at 3 atm of pressure, the bubble content in the emulsion matrix has no significant effect on its critical hot-spot temperature. The results show that the thermal safety of the emulsified matrix decreases with the increase in the content of expanded perlite and environmental pressure, and the influence of environmental pressure is more significant than that of the bubble content. This paper’s research content serves as a reference for a safe emulsified matrix and as an experimental basis for establishing a production line for developing new equipment.

Safety evaluation of offshore oil and gas well string based on corrosion rate prediction

The combined effects of corrosion, temperature, and pressure can cause safety issues such as shortened lifespan and failure of offshore high temperature and high pressure oil and gas well strings. This paper focuses on a certain sea area and conducts experiments on CO2 corrosion of different string materials under different temperature and partial pressure conditions. Combined with the two-phase flow wellbore temperature and pressure-coupling model, a corrosion rate prediction model based on Back Propagation Neural Network optimized by Genetic Algorithm (GA-BPNN) is established for predicting corrosion rate along the wellbore depth. At the same time, based on the API 5C3 standard, considering the degradation effect of thermally induced metal string strength and the influence of environmental pressure, a safety evaluation model of offshore oil and gas well string based on corrosion rate prediction was established, and analysis of the change law of residual strength of the string and prediction of remaining life under the influence of different factors were carried out.

Influence of environmental pressure on the energy coupling and droplet transition behavior in laser welding with filler wire

The influence of environmental pressure on droplet behavior and weld formation in laser welding with filler wire for 304 stainless steel was investigated and the energy coupling behavior was analyzed. As ambient pressure increases from 5 kPa to 700 kPa, the weld depth decreases by 77 %, the variance of the weld width increases approximately 5 times, and the continuity of the weld surface formation deteriorates. During the welding process, a high-speed camera was employed to observe the melt pool, plasma, and melt drop transition behavior. With an increase in the ambient pressure followed by an increase in the metal evaporation temperature, the effects of shielding of the plasma and its internal metal vapor particles on the laser beam lead to a reduction in the depth of the melt. The inverse bremsstrahlung absorption of laser by plasma increased by approximately 36.3 times at 700 kPa compared with that at atmospheric pressure. The number of metal vapor particles at 700 kPa is approximately 3.58 times higher than that at 101 kPa, and the average particle diameter is approximately 0.4 times higher, causing enhanced absorption of laser light by the metal vapor particles. An increase in gas density at elevated ambient pressures resulted in a significant increase in the resistance to droplet descent and decrease in the drive force, leading to an increase in the droplet transition period. This change shifts from a liquid bridge transition to a particle transition, which is the main cause of the deterioration of weld surface formation at high pressures.

Personal Public Transport in Australia: Developments and Prospects

The environmental, social, and economic cost of current car dependence is well known. But people tend to be unwilling to forgo the convenience of private transport. Personal Public Transport (PPT) is a new concept combining the environmental advantages of public transport with the flexibility of the car. The key elements of PPT are new multi-hire modes provided by maxitaxis and taxibuses to supplement single-hire taxis and scheduled services; integration of all modes into a single system; and provision of real-time information and booking systems enabling individual passengers to communicate with the transport system, whether they be at home, on street or in transit.This paper describes how PPT will integrate various technologies, such as automatic vehicle location systems, multi-hire dispatching systems, advanced passenger information systems, and smart card billing systems, together with some of the latest developments in Personal Public Transport.While the technical aspects of PPT are expected to be solvable relatively easily, establishing a complete PPT system will require institutional and regulatory change and a willingness to innovate by both transport operators and regulators. The paper describes changes occurring in Australia in the taxi and bus industries and in regulatory arrangements that will facilitate PPT, and sets out models for establishing PPT systems. It also assesses the potential for PPT from a marketing perspective and its relationship to new developments in urban planning. The paper concludes with a prognosis of how urban transport systems will evolve under the influence of environmental pressures, social values and technological developments, and of how our cities will emerge from the mass transit and private transport eras of the past to the new era of Personal Public Transport and Personal Rapid Transit.

Comparison of Prostate‐Specific Transglutaminase Function in the Great Apes

The copulatory plug is a hardened structure formed through semen coagulation post‐ejaculation which is theorized to protect against remating, stimulate the female reproductive tract, and aid in sperm release and transport. This structure is prevalent in species that experience high levels of sperm competition including chimpanzees and several other primates. Chimpanzees experience high levels of sperm competition due to their polygynandrous mating system. In polygynandry females will mate with multiple partners during an estrus cycle leading to direct competition between the sperm of each male to fertilize the same egg. This varies distinctly from polygynous and monogamous species, such as humans, where females mate with only one male and sperm competition is diminished. Based on previous work in rats, prostate‐specific transglutaminase 4 (TGM4) is implicated as the driving force of the formation of the copulatory plug. TGM4 is a member of the transglutaminase family of enzymes which catalyze the calcium‐dependent formation of an isopeptide bond between glutamine and lysine residues. While humans do not experience a great deal of sperm competition or form a copulatory plug, human semen goes through a similar process of post‐ejaculatory coagulation which is predicted to be carried out by TGM4 under the same mechanism. Interestingly, there are only seven amino acid differences between the human and chimpanzee TGM4s and yet the degree of coagulation between the two species is vastly different. The aim of this study to characterize and compare the function of these proteins to determine the major contributing factor in semen coagulation. The primary hypothesis was that chimpanzee TGM4 would have higher enzymatic activity and more readily cross‐link artificial substrates than human TGM4. To test this hypothesis, the coding sequences were acquired for human and chimpanzee TGM4 as well as eight other primate species. Using a maximum likelihood‐based method, we generated a gene tree of primate TGM4 and calculated dN/dS ratios for each branch. Human TGM4 had a dN/dS ratio of 1.04 suggesting neutral evolution while chimpanzee TGM4 had a ratio of >1 suggesting strong positive selection. We further predicted the sequence of TGM4 of the last human‐chimp ancestor using ancestral sequence reconstruction which utilizes the known phylogenetic tree and a maximum likelihood approach with the software package Phylogenetic Analysis by Maximum Likelihood (PAML). Coding sequences representing TGM4 from humans, chimpanzees, and the last human‐chimp ancestor were cloned into a mammalian expression vector containing a C‐terminal His6tag and were transfected into HEK‐293T cells. Purified TGM4 was used in an in‐vitro colorimetric enzymatic assay to quantify enzymatic activity. Our results suggest that mating system variation has led to differences in both sequence and function of seminal proteins. These functional differences speak to the impact of even a small number of mutations on protein function as well as the influence of environmental pressures on protein evolution.

Research on the Influence of Environmental Pressure on the Combustion Characteristics and Fire Spread of Building External Wall Insulation Materials

Building external wall insulation materials are widely used in the construction industry, which is one of the main materials for building energy saving. In order to study the combustion characteristics and fire spread behaviour of typical exterior wall materials at different pressures. Four environmental pressures of 40KPa, 60KPa, 80KPa, and 101KPa were set in an experimental cabin, measuring the quality, temperature, heat radiation, and heat flow of rigid polyurethane foam (RPU) through experiments. The experimental results are as follows: the masses loss curve of RPU combustion approximately obeyed the quadratic curve, which was similar to the general solid fuel combustion law; the mass change was the most dramatic at 101KPa, the lower the pressure, the slower the mass change; as the pressure decreased, the flame temperature increased slightly, and the spread of the fire slowed down; as the pressure decreased, the peak value of the thermal radiation curve decreased, and the curve tends became flat, but the horizontal axis time increased, indicating that the total heat release remained the same.

The influence of environmental pressure on Internet Use Disorder in adolescents: The potential mediating role of cognitive function

PurposeThe current study attempts to clarify the mediating role of cognitive function on the relationship between environmental pressure (pressure caused by negative parenting styles and dysfunctional school environments) and Internet Use Disorder (IUD); this study explores the effects of sex and left-behind children (LBC). MethodsA cross-sectional sample of adolescents aged 12–15 years was recruited in 2018. A total of 3048 junior high school adolescents in rural areas of the Sichuan province in western China completed a series of psychological inventories, including the Adolescent Pathological Internet Use Scale (APIUS), the Junior High School Students' Perceived School Climate Inventory (PSCI-M), the Egna Minnen av. Barndoms Uppfostran (EMBU), and the Mental Health Screening Inventory for Children and Adolescents (MHS-C), for an analysis of IUD, school climate, parenting styles and cognition, respectively. ResultsAmong the participants, 18.5% (N = 565) exhibited significant symptoms of IUD. The correlation analysis showed that IUD was positively correlated with parents' punishment, rejection and over-interference and academic pressure, whereas IUD was negatively associated with good teacher-student relationships, good schoolmate relationships and cognitive function scores. Structural equation modelling (SEM) showed that cognitive function partially contributed to the association between family and school pressures and IUD. DiscussionCognitive function is one of the mediating pathways through which environmental pressures may predict IUD among junior high school students. Interventions may target the mediating pathway of cognitive function to alleviate the negative impact of environmental pressure on IUD.

Pressure effect on phosphor thermometry using Mg4FGeO6:Mn

This study examined the effect of ambient pressure on the luminescent lifetime of Mg4FGeO6:Mn phosphors in different morphologies. To evaluate the pressure sensitivity of phosphor in the form of particle, agglomerated particle and chemically bonded coating, samples including phosphor powder, a pressed phosphor disc, and chemically bonded phosphor coating were fabricated and calibrated using a PMT-based measurement system for a pressure range of 20–200 kPa and a temperature range of 298–873 K. The results showed no obvious pressure effect on the lifetime of the chemically bonded Mg4FGeO6:Mn coating. However, the lifetime of the phosphor powder and pressed phosphor disc decreased as the pressure increased. This pressure effect was most obvious for the pressed phosphor disc, which was further aggravated at higher temperatures. The atomic distance between the manganese ion and other atomics reduced as the pressure increased, which induced the movement of an excited state in the configuration coordinate. Considering this dependency of pressure sensitivity on phosphor morphology, it is important to adopt the same fabrication procedure for calibration and temperature measurement using Mg4FGeO6:Mn. In addition, for in-flow measurement using Mg4FGeO6:Mn tracer particles, the influence of environmental pressure must be considered.

Investigation and penalty on major industrial accidents in China: The influence of environmental pressures

Hundreds of major industrial accidents happened in China every year which resulted in serious physical and social damage to the whole society. The post-accident investigation and penalties have caused great concern in recent years. Our study extends the research on accident investigation and penalty under different kinds of environmental pressures. Using 150 major industrial accidents and their disclosed investigation reports from the State Administrative of Work Safety of China (SAWSC), we found that the number of administrative penalty, judicial penalty, fines and the accident investigation duration by the government are significantly affected by the environmental pressures including the legal environment pressure, media attention pressure, enterprise ownership pressure and the industry pressure. According to the Deterrence Theory and the Social Learning Theory, the involvement and promptness of penalties significantly influence the deterrent effect for observing peers. Our study shed light on the accident penalties under certain environmental pressure in order to achieve the optimum deterrent effect by giving suggestions to the accident-related stakeholders.

Developing a methodology for a species-based and spatially explicit indicator for biodiversity on agricultural land in the EU

In Europe agricultural areas are of great importance to biodiversity conservation. One of the aims of the Common Agricultural Policy (CAP) after 2013 is to avoid additional loss of agriculture-related biodiversity. Farmland biodiversity is a public good that provides ecosystem services necessary for the sustainability of agriculture itself as well as for a sustainable environment as a whole. To evaluate policies such as the CAP and to monitor the development of biodiversity in agricultural areas, specifically designed indicators are needed. Current EU-level indicators of agricultural biodiversity are often limited to a specific species group, for example the group of farmland birds, and are not designed for evaluation of future policies. This study presents a methodology for a new indicator that is targeted specifically at biodiversity in agricultural areas, considering a large variety of species and focussing on policy. The methodology combines maps of the potential occurrence of 132 relevant species (plants and vertebrates) on a 50km grid, with detailed information (1km grid) on the influence of environmental pressures on these species. A first indicator map on a 1km grid for the EU is provided, based on available data. This map shows great variety in the state of the biodiversity of agricultural areas in the EU. Generally speaking, biodiversity in agricultural areas in the south and east of the EU is in a better state than in the west and north. However, spatial variability is high between and even within regions. The presented indicator may be used to explore the dynamics of biodiversity following policy interventions, using the biodiversity map or by modelling the effect of policies on the environmental pressures that form the basis of the indicator.

Environmental Pressures and Adoption of Training and Development Practices: Understanding the Moderator and Mediator Role of Organizational Values

In this paper, we endeavor to contribute to the theoretical framework of institutionalism concerning the organizational processes of adoption of practices. We chose to investigate, under the conditioning of organizational values, the influence of environmental pressures on the adoption of practices for training and development of industries in the city of Curitiba and its Metropolitan Region. The choice of this type of practice is justified by its instrumental nature within organizations so that their design and implementation can mirror both technical pressures for effectiveness and institutional ones related to social adequacy of the implemented practices. Confronted with this, under the framework of organizational institutionalism, we assume that environmental pressures, usually treated as isomorphic, offer a limited clarification for the phenomenon in question, given the tendency of being seen in the literature as demands for conformity taken for granted while acting on organizational forms and practices. In contrast, we believe that pressures for uniformity do not wipe out the space for organizational action. If, on the one hand, environmental circumstances push towards homogenization, on the other hand, the performance of the isomorphic mechanisms does not eliminate the system of interpretation of each organization, making room for different reference contexts in compliance with the contextual situation in relation to preferences and organizational values. As a result, we assume an ontological attitude based on intersubjectivity, supported by the interpretive capacity of social actors who, under the concept of bounded rationality, add meaning to contextual stimuli. The survey was performed with 54 medium and large industrial organizations located in the city of Curitiba and its Metropolitan Region. The results indicate that both institutional and technical pressures positively influence the adoption of organizational practices. In addition, we can see that competitive and professional values also have an effect on the adoption of such practices, and mediate the impact of pressures on the adoption practices of training and development. This means that companies incorporate as values environment elements, reducing its influence. Finally, we assess the moderating effect of organizational values, comparing the effect of pressures on groups of greater and lesser presence of these values. We can see that in groups of companies whose valuation is high, the influence of institutional pressures is lower than in groups with lower valuation. In the case of technical pressures, they have already shown inconsequential for the highest valuation group, while the group with lesser emphasis on values, they tend to slow down the adoption of practices of training and development. We conclude this article by pointing out some implications of the results shown here for the organizational institutionalism.

Body size and growth: The significance of chronic malnutrition among the Casiguran Agta

Primary objective: The Agta are a short statured, hunter–gatherer population who have been living under demographic and environmental stress. This article shows the influence of these factors and the resulting nutritional deficiency on the anthropometric measurements and mortality of Agta individuals.Research design: The joint analysis of cross-sectional measurements of Agta children and adults and of the mortality schedules in this population aims to stress the influence of environmental pressures on the ongoing evolution of short stature.Methods and procedures: Recumbent length, height, weight, mid-upper arm circumference, and triceps skinfolds were taken using standard methods from a total of 253 Agta individuals. Exact or nearly exact ages were taken from a long-term demographic database. z-Scores and growth curves were calculated using the NutStat program and 2000 CDC reference. Mortality schedules are from published material, improved through interviews in the field.Main outcomes and results: Agta individuals are both short and thin when compared to other populations. Thirty-four per cent of the adults are under-nourished, while 17% of the children are wasted, according to international standards. A major and delayed peak of mortality in early infancy overlaps with a period of average decrease in body length in relation to the reference.Conclusion: Demographic indicators of poor health-related quality of life are consistent with slowed patterns of growth observed, stressing the importance of environmental pressure in maintaining the short stature of the Agta population.

Catalytic Total Oxidation of Methane. Part II. Catalytic Processes to Convert Methane: Partial or Total Oxidation

The introduction of solid catalysts into a traditionally non-catalytic free-radical process such as combustion occurred in recent years under the influence of environmental pressures. The major applications of catalytic combustion are two-fold: at low temperatures to eliminate volatile organic compounds (VOCs) and at high temperatures (>1000°C) to reduce NOx emission from gas turbines, jet motors, etc. It is the high temperature application that is reviewed here. Some recent developments in high-temperature catalytic combustion are trend setters in catalysis and hence of particular interest. For instance, novel materials are being developed for catalytic applications above 1000°C for sustained operation longer than one year. Where material/catalyst developments are still inadequate, systems engineering is coming to the rescue by developing multiple-monolith catalyst systems and the so-called hybrid (catalytic + thermal) reactors.

The Influence of Environmental Pressures, Diversification Strategy, and Union/Nonunion Setting on Employee Participation

This study tests the hypotheses that environment, diversification strategy, and union/nonunion setting affect the number and variety of employee participation programs. A survey of large U.S. manufacturing firms measured the implementation of employee participation programs. Regression results suggest that environmental pressures exert a direct effect on participation in union settings. However, in nonunion settings, environment and diversification strategy both correlated directly with participation. These results suggest that unions could potentially affect participation program implementation.