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Global warming associated with the greenhouse effect urge finding alternative energy strategies concerned with sustainable energy resources that are environmentally friendly and provide energy saving. Waste heat recovery engines are attracting devices that convert usually wasted energy to valuable mechanical or electrical energy. The current research aims to develop a mathematical model to investigate the effects of regenerator physical dimensions on the alpha Stirling engine performance indicators. A mathematical model integrating an internal pressure drop has been proposed to act as a thermodynamic optimization tool for the Stirling engine. The main conclusion was that both geometrical factors and working fluid initial charge (gas mass) craft the performance parameters of alpha type Stirling engine that operates with air as working material. After that, Artificial neural networks of Levenberg Marquardt and Orthogonal Distance Regression models, and Fuzzy systems trained for Mass Charge from M = 0.002 to 0.004 Kg are compared to find the least uncertainty. Results revealed that the Fuzzy system and Orthogonal Distance Regression model could predict more effectively than the Levenberg Marquardt model.

A novel and uncomplicated method for preparing nanocrystalline zinc oxide by precipitation in a basic aqueous solution with the addition of an oxidation agent and in the presence of flowing gas is presented. Firstly, the value of pH of the starting solution containing the zinc salts is adjusted to a value of 5–5.5. Then, zinc oxide is precipitated by adding NH₄OH and bubbling flowing air. Finally, the precipitated materials are washed with a basic solution (0.01 M NaOH). The X-ray diffraction patterns show nanocrystalline single-phase ZnO with a grain size of 12–14 nm (Scherrer method). No further thermal treatment of the prepared material is required. The surface of the prepared material can be successfully modified. This new route is reproducible and can be used on industrial level.

The aerobic oxidative cleavage of styrene C=C double bonds catalyzed by simple manganese porphyrin is reported. Under the catalysis of chloro(tetraphenylporphinato)manganese, the oxidative cleavage of the carbon-carbon double bond of the styrene with air yields benzaldehyde. Our results show that the oxidative cleavage and the epoxidation of the styrene double bond are the competition reactions in the styrene-manganese porphyrin-air system. The reaction temperature decided the product distribution. Under the conditions of 0.4 MPa air and 30 ppm of chloro(tetraphenylporphinato)manganese, the styrene conversion was 20.0% and the selectivity of benzaldehyde and styrene oxide was 81.7% and 12.7% respectively when the reaction temperature was 110°C. Styrene conversion was 92.5% and the selectivity of benzaldehyde and styrene oxide was 48.1% and 41.2% respectively when the reaction temperature was 120°C.

Toluene oxidation with molecular oxygen as the sole oxidant, and μ-oxo-bis[tetraphenylporphinatoiron(III)] as the catalyst, are reported. Under the reaction conditions of 438 K and 0.8 MPa, the molar total yields for the products benzaldehyde and benzyl alcohol and the turnover number of the catalyst are 4.35% and 21,830 (based on the metal ion), respectively. Compared with the reaction catalyzed by the corresponding monometalloporphyrin TPPFe^IIICl, the total yields of the oxidation products and the catalyst turnover number by the dimeric iron porphyrin were almost twice those by the former. A possible reaction mechanism of the toluene oxidation by μ-oxo-bis[tetraphenylporphinatoiron(III)] is proposed.

The five metalloporphyrins (T(p-Cl)PPM, M = Fe, Mn, Co, Cu, Zn) with different metal nuclei were synthesized, and their catalytic aerobic liquid-phase oxidations of p-xylene into p-toluic acid, p-toluic aldehyde and terephthalic acid using a low concentration of acetic acid as solvent without any halide additives, were studied. The p-xylene conversions and the oxidation product distributions were found to be affected by the structures and concentration of the metalloporphyrins as well as the reaction parameters such as time, temperature and air pressure. The formation of some intermediate oxidation products in the oxidation process also influenced the reaction conversions and the product distribution. Among the metalloporphyrins used, tetrakis(p-chlorophenylporphinato)manganese chloride (T(p-Cl)PPMnCl) was the most efficient catalyst for the oxidation of p-xylene. Under the conditions of 180 °C and 2.0 MPa, 44% conversion of p-xylene and 85% selectivity of p-toluic acid were obtained. Based on the results obtained, a preliminary mechanism of the oxidation of p-xylene over metalloporphyrins was proposed.

A systematic study on the effect of a catalyst on the aerobic oxidation of cyclohexane was carried out using cobalt isooctanoate, metalloporphyrin p-ClTPPCo and [p-ClTPPFe]₂O as catalysts. The results showed that the metalloporphyrin-catalyzed system performed better than the traditional cobalt salt (Co isooctanoate) in terms of both the reaction conversion and the selectivity of cyclohexanol and cyclohexanone (KA oil). More importantly, we discovered that bisironporphyrin complex, which was traditionally considered to be either non-active or not-so-active for hydrocarbon oxidation, excelled at 155°C, achieving high selectivity for KA oil (80%) and good reaction conversion (13.8%). This result is in sharp contrast to earlier results by others. Meanwhile, the production of adipic acid was also increased and good selectivity of adipic acid among the by-products was also obtained. Our study suggested that [p-ClTPPFe]₂O catalyzed aerobic oxidation could be used to produce adipic acid in addition to KA oil. Some mechanistic rationales were proposed to explain the superior performance of the [p-ClTPPFe]₂O catalyst based on its unique structural and chemical properties.

Manganese tetraphenylporphyrin supported on nano-TiO₂ has been synthesized and structurally characterized. It has been shown to have excellent catalytic activity for the aerobic oxidation of α-pinene. Experimental results showed that this much-enhanced activity could arise from possible co-catalysis between metalloporphyrin and the nano-TiO₂ support. The catalyst can be reused several times with minor loss to its catalytic activity.

The Clean Air Act (CAA) and Clean Water Act (CWA) have been the lynchpins of the U.S. environmental policy for the last half century. Under both acts the federal government sets standards and the states implement, the outcomes of the CAA and CWA have not been the same however. While criteria air pollutants across the nation have been reduced or maintained under the management control strategies of the CAA, far less is known about the effects the CWA has had on water quality, even though, most agree water quality has improved since its implementation. These acts are built on similar frameworks, but the real difference lies on the embedded identification of assessment criteria. The CAA creates a rigid framework for the consistent identification and monitoring of air pollutants, while the CWA relies on a much more flexible system that varies over space and time. Thus, it is the embedded environmental assessment criteria within these acts that have led to different outcomes for similar policies.

Pollution is a global problem, yet represented by numerous smaller issues at a local level. Greenhouse warming is a global issue that despite its increasing impact remains debated. Regionally, acid rain damaged the forests and lakes of Europe and North America, but was successfully addressed by controlling emissions. Nevertheless, it persists and has become characteristic of China and India. The upper parts of the atmosphere are contaminated by chlorine derived from refrigerants that enhance ozone depletion, though international agreements have reduced this problem. Biomass burning, volcanoes, and windblown dust are seemingly natural processes, yet cause widespread health problems and disrupt air traffic. In the oceans, oil pollution has long been a major problem, although in the current decade it is plastic pollution that has come to dominate public concern. Local air pollution problems typify cities, but are also found around large industrial plants. Air pollutants arise directly as exhaust gases, but are also formed from reactions in the atmosphere, which lead to photochemical smog. Cities additionally suffer from urban runoff that runs across hard surfaces, such as roads and leads to flooding and polluted water. Factories, sewage works, and large point sources add to water pollutants. Legal and fiscal responses, add to technical controls as potential solutions to environmental problems.

Arguably, to nourish or take care of the needs of all of humankind — sustainable and affordable access to clean water, safe sanitation, and clean air, together with a sufficiency of energy, food, and shelter — should be universally available. Yet, many humans do not enjoy such access or availability, even though it has been 70 years since the 1948 United Nations (UN) declaration on human rights proclaimed “that all human beings are equal, and have inherent rights.” However, only food and shelter were explicitly mentioned in the initial declaration. Others were recently added to the UN list, but not air and energy. Nevertheless, basic human needs do not have to be declared as a human right before national actions are taken. Today’s key driver is the UN 2030 Agenda, a plan to eradicate all global poverty and set the world onto a “sustainable and resilient path,” through the achievement of 17 Sustainable Development Goals (SDGs). Adopted by all UN members, the 2030 Agenda in essence, is a 21^st century version of the 1948 proclamation. The SDGs explicitly detail, or implicitly in the case of clean air, all the necessary needs for the nourishing of tomorrow. To achieve the plan will likely require, at least, changes in national cultural values, eliminating inequalities and disparities, developing more appropriate governance strategies, and meaningful technical innovation. In this chapter, these requirements are discussed against a backdrop of presently known deficiencies in global nourishment needs.