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The purpose of this paper is to discuss the chemical characterization of failures and process materials for microelectronics assembly.

The analytical techniques used for chemical structures and compositions including Fourier transform infrared spectrometer (FTIR), scanning electron microscopy, and energy‐dispersive X‐ray spectroscopy are conducted.

The residues on the golden finger are identified to be the flux used in the assembly processes. Besides, the contaminants on the processed and incoming connector pins are verified to be polyamides (–CONH functional groups) from housing material's residue. Three liquid fluxes used in wave soldering are analyzed by their chemical structure. One flux showing the OH groups at 3430 cm⁻¹ indicates higher acid contents. This consists with the acidic values specified by the supplier. Also, the solder mask under study has ever appeared peeled‐off issue. The FTIR spectra results indicated 62.2 percent degree of curing while vendor's spec is above 70 percent.

The establishment of the Infrared spectra database for fluxes and process materials help determine the root cause of the contaminants to reduce re‐occurrence of similar problems and thus enhance the manufacturing capability. The infrared spectrophotometry technique can be used by professional original design manufacturing and/or electronics manufacturing service, providers to investigate board/component defects during product pilot run stage and volume production.

Advancements in real-time water monitoring technologies permit rapid detection of water quality, and threats from waste loads. Water Framework Directive mandating the establishment of Member States’ water resources monitoring, presence of hazardous contaminants in effluents, and perception of vulnerability of water distribution system to attacks, have spurred technical and economic interests. The paper aims to discuss these issues.

As alternative to traditional analyzers, chemosensors, operate according to physical principles, without sample collection (online), and are capable of supplying parameter values continuously and in real-time. Their low selectivity and stability issues have been overcome by technological developments. This review paper contains a comprehensive survey of existing and expected online monitoring technologies for measurement/detection of pollutants in water.

The state-of-the-art in online water monitoring is presented. Application examples are reported. Monitoring costs will become a lesser part of a water utility budget due to the fact that automation and technological simplification will abate human cost factors, and reduce the complexity of laboratory procedures.

An overview of applicable instrumentation, and forthcoming developments, is given. Technological development in this field is very rapid, and astonishing advances are anticipated in several areas (fingerprinting, optochemical sensors, biosensors, molecular techniques). Online monitoring is becoming an ever-important tool not only for compliance control or plant management purposes, but also as a useful approach to pollution control and reduction, minimizing the environmental impact of discharges.

Laboratory investigation of the effect of carbonate contaminant on the rheological properties of drilling mud based on Bingham plastic flow model was carried out. The rheological properties investigated were yield point, plastic viscosity, initial gel strength and ten‐minute gel strength. Eight samples of the same mud were used in the investigation. Equipment used in studying the rheological properties was a direct‐indicating viscometer. The result of the investigation showed that carbonate contaminant in drilling mud adversely increases the yield point and gel strength. Marginal increase in the plastic viscosity of the mud was also observed. The mud flocculated as the amount of carbonate increased.

The purpose of this paper is to explore the environment around the rail track at different sites in Nile Delta region, Egypt, through the measurements of the air pollutants and corrosive ionic species present in surface soil and also to investigate the impact of the existing contaminants on the composition of iron rust formed on the rail head surface at these sites and then the durability of rail itself.

The soil characterization was studied by means of sieve shakers, pH meter, conductivity meter and ion chromatography instrument. Scanning electron microscopy, energy dispersive spectrometry, Fourier transform infrared spectroscopy and X-ray diffraction were used to characterize the rust layer formed on the rail head surface.

The results showed the relation between the contaminants and the composition of the rust layer. Magnetite and goethite were the major phases identified in the rust layers. Akaganeite was detected in the marine atmosphere. Iron sulfide and iron oxide nitrate hydroxide were detected in environments rich in H₂S and NO₂ gases, respectively. The appearance of phases like FeCl₂ and FeOCl only at marine atmospheres reflects that the corrosive species in suspended particulate matter like chloride ion have a higher effect on the rust composition of the rail head surface than that in surface soil layer.

This paper revealed the impact of air and soil contaminants on the composition of rust layer on the rail head surface and may provide guidance for the durability of rails and the necessity for their preservation.

Air pollution is the combination of fine particles and gases in the atmosphere that harm humans and animals. Our objective is to find the various air pollution contaminants and its repercussion on Homo sapiens’ health. We discuss how air quality is measured with the air quality index and measures that help us cope with the consequences of air pollution. To carry out this study, we carried out a systematic literature review to uncover the different dimensions of air pollution and mitigation strategies. From the existing literature and observations of the different data sets, we can conclude that air pollutants have a severe impact on the life of Homo sapiens, causing various diseases such as respiratory issues, skin diseases, etc. Today, we have ample laws, but the need of the hour is to initiate new policies to change the behavioural of Homo sapiens. Our findings will help in decision-making by stakeholders such as policy-makers, manufacturing industries, households, etc. This article will also help in highlighting the need for Homo sapiens behavioural change.

The City of New York was suddenly and deliberately attacked on September 11, 2001, killing thousands of people and leaving unbelievable destruction. Thirty-eight buildings and structures were destroyed or damaged, including seven buildings in the World Trade Center site completely leveled. Almost five years later, two very large contaminated buildings, Deutsche Bank at 130 Liberty Street and Fiterman Hall of Borough of Manhattan Community College, have yet to be cleaned up and demolished. Some 30 million square feet of commercial space was lost. Transportation was disrupted, including the loss of the World Trade Center PATH station, the 1/9 subway line and portions of Route 9A and Church Street. Cars were not allowed south of Canal Street for a week. For Americans this was a terrorist attack and a crime. It was a time for mourning losses and responding to disaster. There was the shock that something like this could happen. And there was more. The destruction of the WTC also posed competing environmental, economic and social threats.

Petroleum hydrocarbons are naturally occurring flammable fossil fuels used as conventional energy sources. It has carcinogenic, mutagenic properties and is considered a hazardous pollutant. Soil contaminated with petroleum hydrocarbons adversely affects the properties of soil. This paper aim to remove pollutants from the environment is an urgent need of the hour to maintain the proper functioning of soil ecosystems.

The ability of micro-organisms to degrade petroleum hydrocarbons makes it possible to use these microorganisms to clean the environment from petroleum pollution. For preparing this review, research papers and review articles related to petroleum hydrocarbons degradation by micro-organisms were collected from journals and various search engines.

Various physical and chemical methods are used for remediation of petroleum hydrocarbons contaminants. However, these methods have several disadvantages. This paper will discuss a novel understanding of petroleum hydrocarbons degradation and how micro-organisms help in petroleum-contaminated soil restoration. Bioremediation is recognized as the most environment-friendly technique for remediation. The research studies demonstrated that bacterial consortium have high biodegradation rate of petroleum hydrocarbons ranging from 83% to 89%.

Proper management of petroleum hydrocarbons pollutants from the environment is necessary because of their toxicity effects on human and environmental health.

This paper discussed novel mechanisms adopted by bacteria for biodegradation of petroleum hydrocarbons, aerobic and anaerobic biodegradation pathways, genes and enzymes involved in petroleum hydrocarbons biodegradation.

The gas emissions towards the atmosphere are one of the main and most actual environmental problems in the world. The effects of greenhouse gas emissions have been studied and treated recently in the Climate Change Conference in Kyoto. In the approved Kyoto Protocol, the European Union will reduce emissions by 8 per cent, the USA by 7 per cent, and Japan by 6 per cent. The data for each country are used to implement policies and make global decisions regarding the level of emissions allowed in the future. For this reason, a study more in depth about the origin and level of emissions from a regional perspective becomes necessary, due to the implications on regional development. The study provides detailed information regarding atmospheric emissions in Spanish regions. Shows that in many cases the atmospheric emissions are not directly related to the economic situations of each region. For this reason, environmental policies should pay attention to the regional differences within a country.

The filterable particles found in electronic solder fluxes vary considerably in both concentration and chemistry. Four fluxes from three manufacturers were examined, including both rosin fluxes and mildly activated resin fluxes. Individual particles were examined by optical light microscopy (OLM) and scanning electron microscopy/energy dispersive X‐ray spectroscopy (SEM/EDX). Finally, an automated SEM/EDX system was used to collect and summarise information about the size and chemistry of a hundred or more particles from each flux. The number of particles per microgram of flux was found to vary by two orders of magnitude (0.004 to 0.4 per μg). The particle diameters ranged from 0.2–20 μm with averages of 1–3 μm. A large fraction of the particles (33–75% by number) were organic substances not soluble in the flux. The bulk of the inorganic particles were composed of sulphates, silicates and metal oxides. Thus, some solder fluxes may be introducing several contaminant particles into each solder contact. These contaminants may affect the quality of the solder joint depending on particle size and composition.