There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

http://publicationslist.org/data/meng.chong/ref-18/sdarticle.pdf

Recent Developments in Photocatalytic Water Treatment Technology: A Review

Photocatalysis has been a widely studied technology since the 1970s. Many investigations have been carried out with the aim of understanding the fundamental processes and enhancing photocatalytic efficiencies especially for water, air, and soil pollution control. In this comprehensive paper, studies focused on the treatment of hazardous wastewater (bearing heavy metals and organic compounds) by photocatalysis and the effects of various parameters such as pH, light intensity, dissolved oxygen, etc., are reviewed. In addition, the design features and efficiencies of various photoreactors used for this process are discussed. Some studies on the economic analysis of photocatalytic systems are also included. It can be concluded that the photocatalysis process is suitable for the treatment of drinking water and industrial wastewater. Also, harvesting the energy of the sun for photoreactions would make it a cleaner and more cost-effective treatment method.

Treatment of Hazardous Organic and Inorganic Compounds through Aqueous-Phase Photocatalysis: A Review

Phthalates are synthesized in massive amounts to produce various plastics and have become widespread in environments following their release as a result of extensive usage and production. This has been of an environmental concern because phthalates are hepatotoxic, teratogenic, and carcinogenic by nature. Numerous studies indicated that phthalates can be degraded by bacteria and fungi under aerobic, anoxic, and anaerobic conditions. This paper gives a review on the biodegradation of phthalates and includes the following aspects: (1) the relationship between the chemical structure of phthalates and their biodegradability, (2) the biodegradation of phthalates by pure/mixed cultures, (3) the biodegradation of phthalates under various environments, and (4) the biodegradation pathways of phthalates.

Phthalates biodegradation in the environment

Xu-dong Wang*,† and Otto S. Wolfbeis*,‡ †Department of Chemistry, Fudan University, 200433 Shanghai, P. R. China ‡Institute of Analytical Chemistry, Chemoand Biosensors, University of Regensburg, D-93040 Regensburg, Germany ■ CONTENTS Books, Reviews, and Articles of General Interest 204 Sensors for (Dissolved) Gases and Vapors 204 Hydrogen 204 Hydrocarbons 206 Oxygen 206 Carbon Dioxide 208 Nitrogen Oxides 208 Other Gases 208 Ammonia 209 Ethanol 209 Other Volatile Organic Compounds (VOC)s 210 Sensors for Humidity, Water Fractions, Hydrogen Peroxide, and Hydrazine 211 Humidity 211 Water Fractions in Organic Solvents 212 Hydrogen Peroxide 213 Sensors for pH Values, Ions, and Salinity 213 pH Values 213 Ions 214 Salinity and Ionic Strength 215 Sensors for Organic Species 216 Glucose Sensing 216 Sucrose 217 Oils 217 Other Organics 217 Biosensors 218 Nucleic Acid-Based Biosensors (DNAand Aptamer-Based) 218 Immunosensors 218 Enzymatic Biosensors 219 Other Biosensors 220 New Schemes and Materials 220 New Sensing Schemes 220 Molecularly Imprinted Polymer (MIP)-Based Sensors 221 Photonic Crystals 223 Author Information 223 Corresponding Authors 223 Notes 223 Biographies 223 Acknowledgments 223 References 223

Fiber-Optic Chemical Sensors and Biosensors (2013-2015).

Preconcentration of trace elements in sea water by complexation with 8-hydroxyquinoline and adsorption on C18 bonded silica gel

Spectrophotometric determination of manganese with 1-(2-pyridylazo)-2-naphthol and a non-ionic surfactant.

Photodegradation of chlorinated hydrocarbons in the presence and absence of dissolved oxygen in water.

Coagulation experiments were performed to find out the optimum coagulant and alkaline chemical for the removal of humic acid (HA) from environmental water. This research clearly indicates the effectiveness of coagulation method using polyaluminum chloride (PAC) with calcium carbonate as neutralizer and coagulant aid to remove HA. The removal of HA was evaluated from absorbance at 260 nm and concentration of dissolved organic carbon (DOC). The highest removal ratio was found to be 96.6% for the absorbance of HA and 91.6% for DOC concentration when 30 mg/L of PAC with calcium carbonate (CaCO3) was used as an alkaline reagent. In this method, the sludge volume (SV) was reduced about half compared with the PAC method using NaOH as neutralizer. Ca2+ which is derived from CaCO3 makes HA colloid size bigger and easier to form flocks because of the compression in the electrical double layer (EDL) between HA colloids. The adsorption of HA onto porous CaCO3 particles also plays an important role. The experiments conducted with sample water collected from Sebangau River, Indonesia consists of 33.4 mg/L of DOC and was found to have a removal efficiency of 86.5%, whereby the final concentration of DOC was 4.5 mg/L. These results suggested that CaCO3 requires a lesser amount of coagulants and also shortens the settling time. This proposed technique provides a more effective and conventional removal method for HA by coagulation–precipitation processes.

Removal of dissolved humic acid from water by coagulation method using polyaluminum chloride (PAC) with calcium carbonate as neutralizer and coagulant aid

The behavior of di(2-ethylhexyl) phthalate (DEHP) discharged from domestic waste water into river water, sediment and submerged aquatic vegetation was investigated. The concentrations of DEHP were found to be between 8-25 microg L(-1) in river water, 1,000-2,000 microg kg(-1) in sediment and less than 20-2,000 microg kg(-1) in submerged aquatic vegetation. The experiments performed in laboratory were on the biodegradation of DEHP in water and sediment, and also adsorption equilibrium of DEHP between water and sediment. The results obtained from the investigations made it clear that the high enrichment of DEHP from water to sediment was caused from not only its high adsorptive potential but also slow degradation in sediment.

Shigeru Taguchi

Papers

Preconcentration of trace elements in sea water by complexation with 8-hydroxyquinoline and adsorption on C18 bonded silica gel

Spectrophotometric determination of manganese with 1-(2-pyridylazo)-2-naphthol and a non-ionic surfactant.

Photodegradation of chlorinated hydrocarbons in the presence and absence of dissolved oxygen in water.

Removal of dissolved humic acid from water by coagulation method using polyaluminum chloride (PAC) with calcium carbonate as neutralizer and coagulant aid

Behavior of di(2-ethylhexyl) phthalate discharged from domestic waste water into aquatic environment