G. Sauerbrey

Bio: G. Sauerbrey is an academic researcher. The author has contributed to research in topics: Thin layers. The author has an hindex of 1, co-authored 1 publications receiving 4625 citations.

Gas Sensors Based on Conducting Polymers

Abstract: The gas sensors fabricated by using conducting polymers such as polyaniline (PAni), polypyrrole (PPy) and poly (3,4-ethylenedioxythiophene) (PEDOT) as the active layers have been reviewed. This review discusses the sensing mechanism and configurations of the sensors. The factors that affect the performances of the gas sensors are also addressed. The disadvantages of the sensors and a brief prospect in this research field are discussed at the end of the review.

Sub–10 nm polyamide nanofilms with ultrafast solvent transport for molecular separation

Abstract: Membranes with unprecedented solvent permeance and high retention of dissolved solutes are needed to reduce the energy consumed by separations in organic liquids We used controlled interfacial polymerization to form free-standing polyamide nanofilms less than 10 nanometers in thickness, and incorporated them as separating layers in composite membranes Manipulation of nanofilm morphology by control of interfacial reaction conditions enabled the creation of smooth or crumpled textures; the nanofilms were sufficiently rigid that the crumpled textures could withstand pressurized filtration, resulting in increased permeable area Composite membranes comprising crumpled nanofilms on alumina supports provided high retention of solutes, with acetonitrile permeances up to 112 liters per square meter per hour per bar This is more than two orders of magnitude higher than permeances of commercially available membranes with equivalent solute retention

Cross-reactive chemical sensor arrays.

Abstract: Conventional approaches to chemical sensors have traditionally made use of a “lock-and-key” design, wherein a specific receptor is synthesized in order to strongly and highly selectively bind the analyte of interest.1-6 A related approach involves exploiting a general physicochemical effect selectively toward a single analyte, such as the use of the ionic effect in the construction of a pH electrode. In the first approach, selectivity is achieved through recognition of the analyte at the receptor site, and in the second, selectivity is achieved through the transduction process in which the method of detection dictates which species are sensed. Such approaches are appropriate when a specific target compound is to be identified in the presence of controlled backgrounds and interferences. However, this type of approach requires the synthesis of a separate, highly selective sensor for each analyte to be detected. In addition, this type of approach is not particularly useful for analyzing, classifying, or assigning human value judgments to the composition of complex vapor mixtures such as perfumes, beers, foods, mixtures of solvents, etc.

Aggregation and deposition of engineered nanomaterials in aquatic environments: role of physicochemical interactions.

Abstract: The ever-increasing use of engineered nanomaterials will lead to heightened levels of these materials in the environment. The present review aims to provide a comprehensive overview of current knowledge regarding nanoparticle transport and aggregation in aquatic environments. Nanoparticle aggregation and deposition behavior will dictate particle transport potential and thus the environmental fate and potential ecotoxicological impacts of these materials. In this review, colloidal forces governing nanoparticle deposition and aggregation are outlined. Essential equations used to assess particle−particle and particle−surface interactions, along with Hamaker constants for specific nanoparticles and the attributes exclusive to nanoscale particle interactions, are described. Theoretical and experimental approaches for evaluating nanoparticle aggregation and deposition are presented, and the major findings of laboratory studies examining these processes are also summarized. Finally, we describe some of the chall...