During roll coating application of water-based architectural paints, fibers are formed between roller and substrate. These fibers progressively thin and break up into several tiny droplets leading to the wastage of paints. This defect is widely known as spattering. In the current study, the propensity to spatter in fully formulated mid pigment volume concentration water-based architectural paints based on varying the type of thickeners, namely a combination of cellulosic with clay, cellulosic, and hydrophobically modified poly acetal/ketal polyether (HMPAPE), at similar and varying volume solids is investigated. The spatter tendency of paint is qualitatively assessed using ASTM D4707. Also, a new approach to quantify the spread area of spattered droplets is developed by thresholding-based image segmentation using an image processing toolbox of Mathematica. This newly developed quantitative approach will greatly help the formulator to better differentiate between formulations. Rheological tests, namely viscosity curve, amplitude sweep, frequency sweep, and first normal stress difference test, are carried out to unravel the flow and viscoelastic properties of paints in depth. An in-house custom-built fiber drawing device on a contact angle drop shape analyzer instrument is fabricated to study the extensional properties of paints. At the same volume solids, the paint based on a combination of cellulosic with clay thickener spatters the most, while the paint based on HMPAPE thickener spatters the least. This is mainly attributed to the chemistry, molecular weight, and thickening mechanism of thickeners. Eventually, a reliable correlation is established between observed spatter and the frequency-dependent elastic modulus outside the linear viscoelastic range at the same and varying solids for paints based on the different types of thickener. This correlation will help chemists to quickly screen formulations to minimize the spattering during roll coat application, thus saving time, cost, and manpower.

Correction for 'Determination of ferric ions using surface-enhanced Raman scattering based on desferrioxamine-functionalized silver nanoparticles' by Fei Yan et al., Chem. Commun., 2013, 49, 7962-7964.

Hardmasks are indispensable materials during pattern transfer to the desired substrates in the semiconductor manufacturing process. Primarily there are two types of hardmask materials - organic and inorganic - and they can be coated onto substrates or underlying materials either by a simple spin-on process or by more expensive methods such as chemical vapor deposition (CVD), atomic layer deposition (ALD) and sputtering process. Most inorganic hardmasks such as SiO2, SiON, SiN and TiN are deposited using the CVD process.Future nodes require hardmasks with high etch resistance as the designs move from horizontal to vertical (3D). We have reported novel spin-on metallic hardmasks (MHM) with comparable or higher etch resistance than SiO2.(1-2) In addition to high etch resistance, they are easy to remove using wet etch chemicals. The spin-on process offers high throughput and commonly used spin tracks can be utilized; thereby reducing overall process costs when compared with CVD.Via-fill performance is also an important attribute of hardmask materials for these future nodes. Organic spin-on materials, both siloxane-and carbon-based, are used in filling applications of deep via or deep trench fill, such as those found in LELE double-patterning schemes. Inorganic materials deposited by either chemical vapor deposition (CVD) or atomic layer deposition (ALD) have higher resistance to oxygenated plasma than organic materials, but are hindered by their poor filling performance. Therefore, novel tungsten (W) containing MHM materials having both good filling performance and higher resistance to oxygenated plasma than organic materials would be of value in some filling applications. The present paper describes specific metal oxides useful for filling applications. In addition to basic filling performance and etch resistance, other properties such as optical properties, outgas and shelf life via forced aging etc. will be discussed.

Two new heteroleptic ruthenium(II) photosensitizers that contains 2,2';6,2''-terpyridine with extended π-conjugation with donor groups, a 4,4'-dicarboxylic acid-2,2'-bipyridine anchoring ligand and a thiocyanate ligand have been designed, synthesized and fully characterized by CHN, mass spectrometry, UV-vis and fluorescence spectroscopies and cyclic voltammetry. The new sensitizers have either 3,5-di-tert-butyl phenyl (m-BL-5) or triphenylamine (m-BL-6) groups, where the molar extinction coefficient of both the sensitizers is higher than the analogous ruthenium dyes. Both the sensitizers were tested in dye-sensitized solar cells using two different redox electrolytes.

In this work, CdSe/ZnS core/shell QDs with emission wavelengths of 535nm, 545nm, 555nm and 575nm were synthesized and the ligands on their surface were exchanged with mercaptopropionic acid (MPA) to make them water-soluble. Hydrophilic QDs were incorporated into a sol–gel GA matrix of 3-aminopropyl trimethoxysilane (APTMS) and 3-glycidoxypropyl trimethoxysilane (GPTMS) to fabricate QD-entrapped membranes. The fluorescence intensity of the QDs entrapped in the sol–gel membrane was increased after being activated by the energy transfer from polycyclic aromatic hydrocarbon compounds (PAHs). The signal increase of the QDs was proportional to the increase in the concentration of the PAHs. Herein, trace levels of anthracene (ANT), phenanthrene (PHE) and pyrene (PYR) were detected through the enhancement of the fluorescence intensity of the CdSe/ZnS QD-entrapped membranes. The linear detection ranges were 0.01–0.1μM for ANT and PHE and 0.005–0.05μM for PYR. The QD-entrapped sol–gel membranes also showed quite good stability for the detection of PAHs over a period of 2 months.

A new high molar extinction coefficient organic-ruthenium(II) polypyridyl complex sensitizer (RD-Cou) that contains 2,,6,-tetramethyl-9-thiophene-2-yl-2,3,5,6,6a,11c-hexahydro1H,4H-11oxa-3a-aza-benzoanthracene-10-one as extended -conjugation of ancillary bipyridine ligand, 4,-dicaboxy-2, ,-bipyridine, and a thiocyanate ligand in its molecular structure has been synthesized and completely characterized by CHN, Mass, 1H-NMR, UV-Vis, and fluorescence spectroscopies as well as cyclic voltammetry. The new sensitizer was tested in dye-sensitized solar cells using a durable redox electrolyte and compared its performance to that of standard sensitizer Z-907.

A strong interaction between cyanide anion and copper(I) cation in combination with non-resonant Raman fingerprinting allows the selective sensing of aqueous free cynanide with high sensitivity to parts per billion (ppb)-level.

This paper describes a direct optical approach based on Raman scattering for selective and sensitive detection of cyanide ions in aqueous environment without requiring time-consuming sample pretreatment and the formation of hydrogen cyanide. Due to the strong affinity between copper (I) and cyanide ion, evaporated copper (I) iodide (CuI) thin films are shown to be excellent substrates for selective recognition of free cyanide ions in aqueous matrices. The amount of cyanide ion retained by the copper (I) in the CuI thin films reflects its actual concentration in tested samples, and the subsequent Raman measurements of the substrate are shown to be capable of detecting toxic cyanide content at levels under international drinking water standard and environmental regulatory concentrations. Measurements obtained from the same batch of evaporated CuI thin films (∼100-nm thickness) show excellent linearity over a variety of cyanide concentrations ranging from 1.5μM to 0.15mM. This detection method offers the advantage of selectively detecting cyanides causing a health hazard while avoiding detection of other common interfering anions such as Cl−, Br−, PO43−, SO42−, NO2−, S2− and SCN−. Coupled with portable Raman systems that are commercially available, our detection approach will provide on-site monitoring capability with little sample preparation or instrument supervision, which will greatly expedite the assessment of potential environmental cyanide risks.

We are currently developing a detection system based on the principles of infrared (IR) spectroscopy that operates in heterogeneous aqueous environments and provides fast detection (<10 min) and high sensitivity/selectivity to nonvolatile toxic materials with minimal false alarms. The key enablers to using IR spectroscopy for aqueous-based detection are the development of selective and robust sampling protocols. In this paper, we describe a new sampling approach based on the use of reactive thin films sublimed onto an IR amenable support. The films chemically react with a predefined class of compounds and identification of the specific chemical is provided by IR spectral analysis. Proof of concept of this approach is demonstrated for the detection of cyanide in water. Specifically, CuI has been vacuum sublimed on silicon wafers, and upon exposure to solutions of NaCN, CuCN is formed producing a single sharp band at 2173 cm-1. The intensity of this band varies linearly with NaCN concentration, and it is shown that a detection limit below 100 ppb (parts per billion) is achievable.

Two efficient heteroleptic ruthenium (II) complexes, cisdi(thiocyanato)(4,4'-dicarboxylic acid-2,2'-bipyridine)(4,4'-bis(2(3,5-di tert- butylphenyl) ethenyl)-2,2'-bipyridine)ruthenium (II) (HRD-1) and cis-di(thiocyanato)(4,4'-dicarboxylicacid-2,2'-bipyridine)(4,4'-bis(2-(2,3,5-trimethylphenyl)ethenyl)-2,2'-bipyridine) ruthenium (II) (HRD-2) were synthesized and characterized, which when anchored onto nanocrystalline TiO2 shows efficiency of 5.77 and 4.87% respectively, using durable redox electrolytes.

The resistance changes of CuBr upon exposure to carbon monoxide (CO) are explored as the sensing principle in this study. X-ray diffraction and thermal analysis were used to characterize the CuBr. Thick-films of CuBr deposited on an alumina substrate with gold interdigitated electrodes were used as the sensing element. Interaction with CO led to decrease in electrical resistance of the films. The presence of H-2 in the background gas did not influence the resistance. Humidity, on the other hand did change the background resistance, but at constant humidity, the sensor exhibited resistance changes with CO. This sensor could be useful for CO detection in the hydrated environment of polymeric-based fuel cell systems that use hydrocarbons. (C) 2003 Elsevier Science B.V. All rights reserved.