Bøger udgivet af LAP Lambert Academic Publishing

As we face global population growth, increased competition for land and water resources from industrial and urban growth, climate change and the need to protect the environment, we need new solutions to increasing agricultural productivity to combat hunger and poverty. One particularly effective form of bioconversion biotechnology is mushroom cultivation for food, and also for the production of mushroom derived substances. Mushroom production is so far the most profitable way of utilizing ligno-cellulose containing waste materials into foods of higher yields, protein and gross energy per unit area of land. This book investigates the effect of compost size/height, composting period and supplementation on the yield of mushrooms. Mushrooms are gaining popularity due to its nutritive, medicinal and spiritual uses.

Pleurotus tuberregium is of great economic importance in all parts of sub-Saharan African, especially in Nigeria. Both the sclerotium and the mushrooms grown from it are eaten. In view of its popularity (use as food condiment and in medicine), it became necessary to study the simplest and cheapest substrate that would give the highest weight yield and protein content for its production. The mushroom is important for three main reasons: as a source of food (plus health benefits), as a source of income and to maintain the health of forests.

The central problem addressed is how when an emulsion is used as a lubricant, an oil droplet may be brought to steel substrate to provide microhydrodynamic lubrication. This happens by disjoining a thin water film adhered to steel substrate separating oil from substrate. Quantum mechanical and thermodynamic insights are considered to build a model. The model may be manipulated by selection surfactants and substrates of different chemical potentials to create situations, which enable the disjoining of water film. Different types of forces using atomic force microscopy and physic-chemical methods to validate the model and come to the conclusion, that for a given chemical potential only when the droplet size is controlled by surfactant chemistry and concentration to remain below a critical size it is possible to create a strongly attractive regime between the oil and the steel to bring about the disjoining process. The author demonstrates experimentally for a range of substrates, surfactants and their concentrations in the media, that there is a combination, as suggested by his theoretical model, for which the coefficient friction, in steel on steel sliding experiment, is optimum.

A cosmological model was developed using a quantum equation of state of hidden photon gas, as well as cosmic time. One of the primary objectives of this model is to see if determining the observed rotation speed of galactic matter is possible, without using dark matter DM (halo) as a parameter. To do so, a numerical application of the evolution of variables in accordance with cosmic time and a new state equation was developed to determine precise, realistic values for a number of cosmological parameters, such as energy of the universe U, cosmological constant Λ, curvature of space k, energy density, age of the universe etc. The current version of the model partially explains several of the observed phenomena that raise questions since CMB and JWST (VETG, Hubble tension, SMBH).

The economic trajectory of Ghana has been notably dynamic in recent years, consistently ranking among the top ten fastest-growing economies in Africa since 2017. However, the year 2020 brought unprecedented challenges, as plummeting oil prices and the onset of the COVID-19 pandemic precipitated a significant economic downturn, plunging the nation into recession. Through this analytical lens, this book was able to unravel the intricate interplay of diverse socio-economic factors and their respective contributions to the observed patterns of unemployment amid the COVID-19 crisis. Notably, this book reveals that the burgeoning financial burdens stemming from unemployment, coupled with the pervasive apprehension surrounding job security, collectively exert upward pressure on the national public debt. By foregrounding these hitherto underexplored dimensions, the study advances our understanding of the nuanced determinants of unemployment amid the COVID-19 crisis, thereby offering valuable insights for policymakers, researchers, and practitioners alike.

У навчальному посібнику представлені 8 лабораторних робіт з визначення поверхневої, проекційної та об'ємної твердості металів, вимірюваних за допомогою твердомірів Брінелля, Роквелла, Віккерса, Nano Test. Кожна робота представляє закінчене наукове дослідження, що дає змогу значно поширити функціональні можливості сучасних твердомірів. Для кожного метода розроблені та апробовані відповідні формули та детально прописана методика досліджень. Ці лабораторні роботи в першу чергу орієнтовані на аспірантів та студентів технічних навчальних закладів, но можуть також використовуватися на металургійному виробництві і в машинобудуванні для оцінки якості продукції за методами визначення твердості. Всі роботи пройшли апробацію у продовж останніх 10 років, набрали позитивний досвід і можуть бути рекомендовані для активного втілення у навчальний процес технічних університетів.

In an internal combustion engine, the cylinder head (often informally abbreviated to just head) sits above the cylinders on top of the cylinder block. It closes in the top of the cylinder, forming the combustion chamber. This joint is sealed by a head gasket. In most engines, the head also provides space for the passages that feed air and fuel to the cylinder, and that allow the exhaust to escape. The head can also be a place to mount the valves, spark plugs, and fuel injectors. The major automobile component subject to high temperature variation and thermal stress is engine cylinder. Fins are used on the surface of engine cylinder to increase the heat transfer rate. Heat rejection rate in engine cylinder fins can be enhanced by increasing its surface area. The objective of the present investigation is to examine the thermal properties by varying geometry, and material cylinder fins using solid works and Ansys work bench and the models are created by changing the geometry like (i) no of fins (ii) fin thickness (iii) gap between fins.

The Burgenland Croats have been present in Austria for the last 500 years. The subject of their role in Austrian political life has not been researched so far, so this text hopefully will shed new light on this part of their presence. Besides the strong cultural heritage that they preserve, the questions of how the status of Burgenland Croats as a minority in Austria is and how strong their influence on political life in Austria is were examined, as well as their position inside the Austrian society. The literature review and the theoretical approach included various theories that helped to understand better the political status of the Burgenland Croats, along with the qualitative research method based on interviews as a collection of data, that revealed a new perspective regarding the status and understanding of Burgenland Croats in Burgenland and Vienna. One of the conclusions definitely would be that there is a big space for more political progress, both from Croatian and Austrian authorities and governments.