Quaternary Ammonium Chloride Research Articles

Nanofiltration, bipolar electrodialysis and reactive extraction hybrid system for separation of fumaric acid from fermentation broth

A novel approach based on a hybrid system allowing nanofiltration, bipolar electrodialysis and reactive extraction, was proposed to remove fumaric acid from fermentation broth left after bioconversion of glycerol. The fumaric salts can be concentrated in the nanofiltration process to a high yield (80–95% depending on pressure), fumaric acid can be selectively separated from other fermentation components, as well as sodium fumarate can be conversed into the acid form in bipolar electrodialysis process (stack consists of bipolar and anion-exchange membranes).Reactive extraction with quaternary ammonium chloride (Aliquat 336) or alkylphosphine oxides (Cyanex 923) solutions (yield between 60% and 98%) was applied as the final step for fumaric acid recovery from aqueous streams after the membrane techniques. The hybrid system permitting nanofiltration, bipolar electrodialysis and reactive extraction was found effective for recovery of fumaric acid from the fermentation broth.

Enhanced adsorption of aqueous perchlorate on quaternary ammonium chloride surfactant-modified activated carbon fibers

Perchlorate contamination of drinking water and groundwater is a worldwide concerned issue, and technologies are needed for the treatment of aqueous perchlorate. In this study, activated carbon fibers (ACFs) and quaternary ammonium chloride surfactant-modified ACFs were tested for perchlorate removal from aqueous solution. The ACFs modified by cetyltrimethyl ammonium chloride (CTAC) exhibited the best performance on perchlorate adsorption. Batch experiments were performed to investigate the equilibrium, thermodynamics, kinetics, and mechanism of perchlorate adsorption onto CTAC-ACFs. The results showed that the spontaneous perchlorate adsorption process followed the Langmuir isotherm and the pseudo-second-order kinetic model. Perchlorate adsorption onto CTAC-ACFs was enhanced as the initial perchlorate concentration, contact time, and solution temperature increased. Alkaline pH and higher ionic strength did not favor the adsorption of perchlorate. Ion exchange between the perchlorate and carried chloride was the major adsorption mechanism, but other adsorption processes (e.g. electrostatic attraction and physical adsorption) may also play important roles for the adsorption. The CTAC-ACF adsorbent showed a relatively high adsorption capacity of 26.74 mg/g (at an initial perchlorate concentration of 20 mg/L). Moreover, its well stability and regenerability enable it as a potential adsorbent material for the decontamination of aqueous perchlorate.

Synthesis of quaternary ammonium hydroxide from its halide salt by bipolar membrane electrodialysis (BMED): effect of molecular structure of ammonium compounds on the process performance

AbstractBACKGROUNDConventional methods for synthesis of quaternary ammonium hydroxides, such as the reaction of quaternary ammonium chloride, ion‐exchange and electro‐electrodialysis cannot achieve benign production of QAOH without secondary pollution. The objective of the present study was to develop bipolar membrane electrodialysis with a novel stack configuration as an improved method to prepare high purity quaternary ammonium hydroxide from its halide salt.RESULTSTo investigate the synthesis of quaternary ammonium hydroxide (QAOH) with high purity by using electrodialysis with bipolar membranes (BMED), four different types of quaternary ammonium hydroxides (tetramethylammonium hydroxide, TMAOH; tetrapropylammonium hydroxide, TPAOH; methyltriethylammonium hydroxide, MTAOH; and benzyltrimethylammonium hydroxide, BTAOH) were chosen as the target products. The effect of the molecular structure of four different types of halide salts (NR4X) on the BMED performance was studied by investigating operating parameters such as current density, feed concentration and feed flow velocity and energy consumption on the basis of ion dimensions and molecular weight, ion electrophoretic mobility and the interaction between ammoniums and membranes. The results indicate that it is feasible to obtain quaternary ammonium hydroxides with high purity (Cl−/Br− content < 500 ppm) by BMED with a novel four‐compartment configuration in view of environmental aspects.CONCLUSIONFor converting higher molecule size halide salts, the process performance was lower, while the energy consumption increased, at similar experimental conditions, which is in line with the theory. © 2014 Society of Chemical Industry.

Reporter-Free Potentiometric Sensing of Boronic Acids and Their Reactions by Using Quaternary Ammonium Salt-Functionalized Polymeric Liquid Membranes

The tremendous applications of boronic acids (BAs) in chemical sensing, medical chemistry, molecular assembly, and organic synthesis lead to an urgent demand for developing effective sensing methods for BAs. This paper reports a facile and sensitive potentiometric sensor scheme for heterogeneous detection of BAs based on their unexpected potential responses on quaternary ammonium salt-doped polymeric liquid membranes. (11)B NMR data reveal that a quaternary ammonium chloride can trigger the hydrolysis of an electrically neutral BA in an aprotic solvent. Using the quaternary ammonium salt as the receptor, the BA molecules can be extracted from the sample solution into the polymeric membrane phase and undergo the concomitant hydrolysis. Such salt-triggered hydrolysis generates H(+) ions, which can be coejected into the aqueous phase with the counterions (e.g., Cl(-)) owing to their high hydrophilicities. The perturbation on the ionic partition at the sample-membrane interface changes the phase boundary potential and thus enables the potentiometric sensing of BAs. In contrast to other transduction methods for BAs, for which labeled or separate reporters are exclusively required, the present heterogeneous sensing scheme allows the direct detection of BAs without using any reporter molecules. This technique shows superior detection limits for BAs (e.g., 1.0 × 10(-6) M for phenylboronic acid) as compared to previously reported methods based on colorimetry, fluorimetry, and mass spectrometry. The proposed sensing strategy has also been successfully applied to potentiometric indication of the BA reactions with hydrogen peroxide and saccharides, which allows indirect and sensitive detection of these important species.

Type and Concentration Effects of some Active Ingredients on the Performance of Bentonite Lubricant Grease

Optimization study was carried out on the materials used in preparation of lubricant grease
 prepared from bentonite. This study included the selection of the optimum type and percent of
 quaternary ammonium salts to convert the bentonite from hydrophilic to organophilic; tetraethyl
 ammonium chloride and tetraethyl ammonium bromide were used for this purpose. It was seen that
 the quaternary ammonium chloride gave the best results because of the high tendency of calcium
 ion to react with chloride ion than that with bromide ion; over more it gave a less swelling.
 The effect of treated bentonite added in different percentage on the penetration point, NLGI
 (National Lubricating Greases Institute number), drop point, and water resistance of the prepared
 grease was studied. It was seen that by increasing the percentage of added organophilic bentonite
 with the prepared grease caused a decrease in the penetration point which is correspond to increase
 in the consistency of stiffness of grease. These results were in agreement with the NLGI
 classification system. It was noticed that by increasing the percentage of added organophilic
 bentonite in the prepared grease caused an increase in the dropping point and in the degree of
 water resistance.

Excited-State Proton Transfer of Fluorescein Anion as an Ionic Liquid Component

Fluorescent ionic liquids (FILs) incorporating the fluorescein anion have been prepared by anion exchange of the parent quaternary ammonium chloride (Quat(+)Cl(-)) ionic liquid. By controlling the molar ratio of fluorescein to Quat(+)Cl(-), ionic liquids incorporating different prototropic forms of fluorescein were prepared. The 1:1 molar ratio ionic liquid (FIL1) is essentially composed of monoanionic fluorescein, while dianionic fluorecein is predominant in the FIL with a 1:2 molar ratio (FIL2). The fluorescence excitation spectrum of FIL2 is markedly different from its absorption spectrum. Absorption features the fluorescein dianion, while the excitation spectrum is exclusively due to the monoanion. In FIL1, the absorption and excitation spectra are both characteristic of the monoanion. In both FILs, emission of the dianion is observed upon excitation of the monoanion. This unusual behavior is interpreted in the context of a fast deprotonation of the monoanion in the excited state. The presence of residual water in the ionic liquid is important for the proton transfer process. By lowering the pH of FIL1, the transient proton transfer is inhibited, and the emission of the monoanion could be observed. The FILs have completely different spectroscopic properties from solvated fluorescein in Quat(+)Cl(-), where the prototropic equilibrium is shifted toward the neutral forms.

Antifungal activity of gemini quaternary ammonium salts

A series of gemini quaternary ammonium chlorides and bromides with various alkyl chain and spacer lengths was synthesized. The most active compounds against fungi were chlorides with 10 carbon atoms within the hydrophobic chain. Among these compounds were few with no hemolytic activity at minimal inhibitory concentrations. None of the tested compounds were cytotoxic and mutagenic. Cationic gemini surfactants poorly reduced the adhesion of microorganisms to the polystyrene plate, but inhibited the filamentation of Candida albicans. One of the tested compounds eradicated C. albicans and Rodotorula mucilaginosa biofilm, what could be important in overcoming catheter-associated infections. It was also shown that gemini surfactants enhanced the sensitivity of C. albicans to azoles and polyenes, thus they might be potentially used in combined therapy against fungi.

New surface hydroxylated and internally quaternised poly(propylene imine) dendrimers as efficient biocompatible drug carriers of norfloxacin

Objectives: This study intended to describe the development of two novel, biocompatible and potential surface hydroxylated quaternary ammonium chloride based poly(propylene imine) (PPI) dendrimers for effective delivery of the drug Norfloxacin (NFN).Methods: The synthetic pathway involved the hydroxylation and methylation of generation 2 and 3 PPI dendrimers and thus produced surface hydroxylated and internally quaternised PPI dendrimers viz., QPPI-OH (G2) and QPPI-OH (G3), respectively. The potential of these dendrimers were examined as drug carrier for NFN, by carrying out solubility, in vitro release, cytotoxicity and anti-bacterial studies.Results: It was observed that the QPPI-OH (G2)/QPPI-OH (G3) dendrimers have excellent solubilising potential/drug loading abilities of NFN in aqueous medium and can also sustain delivery of NFN. The effective complexation of NFN with QPPI-OH (G2) and QPPI-OH (G3) increased the solubility of NFN and thus elevates the NFN drug from Class 4 to Class 3 (according to BCS). These dendrimers increase the biocompatibility and increase the tolerance concentration during drug–dendrimer formulations. Anti-bacterial studies showed that the efficacy of the drug was increased in the presence of dendrimer carriers.Conclusions: These results indicate that the QPPI-OH (G2) and QPPI-OH (G3) dendrimers might be considered as potential biocompatible drug carriers of fluoroquinolines under suitable conditions.

New Role of Layered Silicates as Phase Transfer Catalyst for In Situ Polymerization of Poly(ethylenetetrasulfide) Nanocomposite

In this study, polyethylenetetrasulfide/montmorillonite nanocomposite (PETS/nanoclay) is synthesized from ethylene dichloride and sodium tetrasulfide monomers by in situ polymerization method. The effect of phase-transfer catalyst (PTC) on polymerization kinetics in addition to the structure of resulting PETS containing nanoclay is investigated. The results show that surface-modified montmorillonites by methyl tallow bis-2-hydroxyethyl quaternary ammonium chloride could properly act as PTC. Therefore, it is demonstrated that the addition of nanoclay as PTC reduces the reaction time and increases the polymerization rate during the production of final nanocomposite. The samples were characterized using Fourier transform infrared and Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), nuclear magnetic resonance spectroscopy besides energy-dispersive X-ray spectroscopy (EDS) combined with SEM (SEM–EDX). In addition, thermal behavior of nanocomposite was perused by differential scanning calorimetry and thermogravimetric analysis. XRD and AFM results show proper dispersion of clay in PETS matrix and SEM–EDX results demonstrate suitable distribution of clay in polymer matrix. PETS/nanoclay nanocomposite show a better thermal stability, and also higher glass transition and melt temperature compared to pure polysulfide polymer. The solubility of nanocomposite is also studied and results show that the solubility depends on solvent concentration in addition to reinforcement (nanoclay) deals.

Disinfectant and Antibiotic Susceptibility Profiles of Escherichia coli O157:H7 Strains from Cattle Carcasses, Feces, and Hides and Ground Beef from the United States

The disinfectant and antibiotic susceptibility profiles of 344 Escherichia coli O157:H7 strains from cattle carcasses, feces, and hides and ground beef from the United States were determined. A low prevalence of antibiotic resistance was observed (14%). The highest prevalences of resistance were to sulfisoxazole (10.5%), tetracycline (9.9%), streptomycin (7%), and chloramphenicol (4.9%). Four strains were resistant to eight antibiotics (two strains from ground beef and one strain each from hide and preevisceration carcass swabs of cull cattle at harvest). Pulsed-field gel electrophoresis analysis of the E. coli O157:H7 strains revealed two major groups (designated 1 and 2) composed of 17 and 20 clusters, respectively. Clusters 1A, 1B, 1C, and 1G.1 were associated with multidrug-resistant strains. There was no observed correlation between disinfectant resistance and antibiotic resistance. Sixty-nine (20%) of the 344 strains were resistant to chlorhexidine or benzalkonium chloride or the MICs of benzyldimethyldodecylammonium chloride were elevated. Inducible resistance was observed at elevated concentrations of antibiotics (1.4%) and disinfectants (6.1%). The highest rate of disinfectant inducible resistance was to OdoBan, quaternary ammonium chlorides, and the surface disinfectants F25, FS512, and MG, which are used in dairies, restaurants, and food processing plants. High MICs (1,024 to 4,096 m g/ml) of acetic, lactic, and citric acids were found. The decreasing order of acid potency based on molar MICs (MICs(molar)) was acetic, citric, and lactic acid. The correlation of the concentration of dissociated organic acids and MICs(molar) strongly suggests that the observed inhibition of E. coli O157:H7 was primarily due to dissociated forms of the acids.

Medical Implications of Antimicrobial Coating Polymers- Organosilicon Quaternary Ammonium Chloride

Hospital-Associated Infections (HAI) are commonly caused by the invasive device and prosthesis implanted in the body. The practice of coating antimicrobial agents on biomedical surfaces or modifying the composite resin with such agents has been shown effective in reducing the incidence of HAI. Quaternary Ammonium Chloride (QAC) salts and the Organosilicon derivatives (OrganoSiQAC) are surface active to serve these applications. Clinically, Benzalkonium chloride (BAC) is effective against a board range of microorganisms. However, it has been recognized as the source of several hospital outbreaks due to contamination with gram-negative bacteria. Safety aspects such as potential toxicities and in vivo efficacies were poorly defined. On the other hand, physical antimicrobial polymers formed by OrganoSiQAC compounds were found to be chemically stable and nonleachable from the bonded surface, whereas the biocidal effects were exerted by the end satellite QAC groups. Recent studies have also reported the application of such bioactive films on animated surfaces such as skin and mucosal lining. This opens the future perspective with multiple applications in infection control, in the regards of reduce use of antibiotics, treatment alternatives for multiple antibiotic resistance, blocking the route of transmission of specific organisms in clinical and community settings.

Branched Polymeric Media: Perchlorate-Selective Resins from Hyperbranched Polyethyleneimine

Perchlorate (ClO(4)(-)) is a persistent contaminant found in drinking groundwater sources in the United States. Ion exchange (IX) with selective and disposable resins based on cross-linked styrene divinylbenzene (STY-DVB) beads is currently the most commonly utilized process for removing low concentrations of ClO(4)(-) (10-100 ppb) from contaminated drinking water sources. However, due to the low exchange capacity of perchlorate-selective STY-DVB resins (∼0.5-0.8 eq/L), the overall cost becomes prohibitive when treating groundwater with higher concentration of ClO(4)(-) (e.g., 100-1000 ppb). In this article, we describe a new perchlorate-selective resin with high exchange capacity. This new resin was prepared by alkylation of branched polyethyleneimine (PEI) beads obtained from an inverse suspension polymerization process. Batch and column studies show that our new PEI resin with mixed hexyl/ethyl quaternary ammonium chloride exchange sites can selectively extract trace amounts of ClO(4)(-) from a makeup groundwater (to below detection limit) in the presence of competing ions. In addition, this resin has a strong-base exchange capacity of 1.4 eq/L, which is 1.75-2.33 times larger than those of commercial perchlorate-selective STY-DVB resins. The overall results of our studies suggest that branched PEI beads provide versatile and promising building blocks for the preparation of perchlorate-selective resins with high exchange capacity.

Biofilm formation by Shiga toxin-producing Escherichia coli O157:H7 and Non-O157 strains and their tolerance to sanitizers commonly used in the food processing environment.

Shiga toxin-producing Escherichia coli (STEC) strains are important foodborne pathogens. Among these, E. coli O157:H7 is the most frequently isolated STEC serotype responsible for foodborne diseases. However, the non-O157 serotypes have been associated with serious outbreaks and sporadic diseases as well. It has been shown that various STEC serotypes are capable of forming biofilms on different food or food contact surfaces that, when detached, may lead to cross-contamination. Bacterial cells at biofilm stage also are more tolerant to sanitizers compared with their planktonic counterparts, which makes STEC biofilms a serious food safety concern. In the present study, we evaluated the potency of biofilm formation by a variety of STEC strains from serotypes O157:H7, O26:H11, and O111:H8; we also compared biofilm tolerance with two types of common sanitizers, a quaternary ammonium chloride-based sanitizer and chlorine. Our results demonstrated that biofilm formation by various STEC serotypes on a polystyrene surface was highly strain-dependent, whereas the two non-O157 serotypes showed a higher potency of pellicle formation at air-liquid interfaces on a glass surface compared with serotype O157:H7. Significant reductions of viable biofilm cells were achieved with sanitizer treatments. STEC biofilm tolerance to sanitization was strain-dependent regardless of the serotypes. Curli expression appeared to play a critical role in STEC biofilm formation and tolerance to sanitizers. Our data indicated that multiple factors, including bacterial serotype and strain, surface materials, and other environmental conditions, could significantly affect STEC biofilm formation. The high potential for biofilm formation by various STEC serotypes, especially the strong potency of pellicle formation by the curli-positive non-O157 strains with high sanitization tolerance, might contribute to bacterial colonization on food contact surfaces, which may result in downstream product contamination.

Mechanical and Gas Barrier Properties of Nylon 6/Clay Nanocomposite Blown Films

Nylon 6/clay nanocomposite films were prepared by melt mixing nylon 6 with organoclay using a twin screw extruder attached to a blown film die. The type of surfactant used in the pretreatment of organoclay was expected to affect the degree of clay dispersion, which would in turn affect the degree of crystallinity, crystalline phase and bulk properties of the polymer composite. Two different surfactants used to treat the surface of montmorillonite clay were trimethyl tallow quaternary ammonium chloride (M 3 T, a single-chain surfactant) and dimethyl bis (hydrogenated-tallow) ammonium chloride (M 2 (HT) 2 , a double-chain surfactant). The addition of the resulting organoclay into nylon 6 was found to enhance the formation of γ-phase and increase the degree of crystallinity and crystallization temperature of the nylon 6. In fact nanocomposite films containing the single-chain surfactant showed a higher degree of clay dispersion in nylon 6 matrix, up to 148% higher stiffness and up to 100% lower oxygen permeability than those films containing the corresponding double-chain surfactant at the same inorganic loadings investigated. As expected, the nanocomposite films exhibited 58% higher stiffness in the machine direction than the transverse direction.

Antiviral Efficacy of Citra-kill®, Disinfectant Solution Against Avian Influenza Virus

본 연구에서는 4급 암모늄에 속하는 quaternary ammonium chloride와 구연산의 합제인 Citra-<TEX>$Kill^{(R)}$</TEX>의 조류인플루엔자에 대한 살바이러스 효과를 확인하기 위해 국립수의과학검역원의 소독제 효력시험 중 바이러스 소독제 효력시험에 따라 수행하였다. 소독제와 조류인플루엔자바이러스를 증류수, 경수, 그리고 유기물 조건에서 반응시킨 후, 중화액을 이용하여 중화시킨 다음, 중화된 용액 0.2 ml를 10일령의 계태아 요막에 주입하여 5일 동안 배양시킨 다음, 요막액을 채취하여 바이러스의 생존여부를 혈구응집반응을 통해 확인하여 소독제의 효력배수를 결정하였다. 본 연구의 결과, Citra-<TEX>$Kill^{(R)}$</TEX>은 증류수, 경수, 그리고 유기물 조건에서 각각 2,000, 1,500, 그리고 500배에서 조류인플루엔자바이러스를 불활성화시켜, 조류인플루엔자에 대해 뛰어난 소독효과를 갖고 있는 것이 확인되었다. 따라서 향후, 야외적용시험을 통해 실제적용에 따른 효과를 확인할 필요가 있을 것으로 사료된다. Highly pathogenic avian influenza virus (HPAIV) is already panzootic in poultry and caused a considerable economic loss in poultry industry. In addition, HPAIV continues to cross species barriers to infect humans and other mammals, often with fatal outcomes. In this study, the virucidal efficacy of Citra-<TEX>$Kill^{(R)}$</TEX> composed to quaternary ammonium chloride and citric acid was investigated against avian influenza H9N2 virus (AIV). A virucidal efficacy was determined with the viability of AIV contacted with the disinfectant in the allantoic membrane of chicken embryos. Citra-<TEX>$Kill^{(R)}$</TEX> and AIV was reacted on the distilled water (DW), hard water (HW) or organic matter suspension (OM) condition. On DW condition, AIV was inactivated with 2,000 fold dilutions of Citra-<TEX>$Kill^{(R)}$</TEX>. When the antiviral effect on HW condition was evaluated, the antiviral activity of the disinfectant showed on 1,500 fold dilutions against AIV. With the investigation of the antiviral effect of the disinfectant on OM condition, AIV was inactivated on 500 fold dilutions of Citra-<TEX>$Kill^{(R)}$</TEX>. As Citra-<TEX>$Kill^{(R)}$</TEX> possesses virucidal efficacy against AIV, the disinfectant solution can be used to limit the spread of animal viral diseases.

Infection control in general practices in Buffalo City and OR Tambo District Municipalities, South Africa

BackgroundGood infection control practices are effective in reducing rates of infection in health care settings. Studies in primary care in developed countries indicate that many general practitioners (GPs) do not comply with optimal infection control practices. There are no published studies from developing countries in Southern Africa.ObjectivesThe aim of this study was to describe infection control practices in private GP surgeries in the Buffalo City and OR Tambo District Municipalities in the Eastern Cape Province, South Africa.MethodA literature review was conducted to appraise current best practice with respect to Standard Infection Control and Transmission Based Precautions. A questionnaire, inquiring into GPs’ actual practices, was posted to each surgery.ResultsThe valid response rate was 34% (47/140). Methods used to sterilise instruments in 40 practices were: ultraviolet sterilisation (23), chemical disinfection (14), boiling water (7), and steam autoclave (2). Compounds used for chemical disinfection included organotin quaternary, chlorhexidine and benzyl ammonium chloride with a quaternary complex. Twenty-two (47%) used a hand rub. Sixteen (35%) GPs stated that they had a policy to promptly triage patients who are coughing, and 23 (50%) had a policy for airflow movement in the surgery. All practices appropriately disposed of sharps. Thirty-seven (80%) expressed interest in a seminar on infection control.ConclusionsOverall, GPs were aware of infection control precautions. Ultraviolet sterilisers and chlorhexidine are not recommended, however, for sterilisation or high level disinfection of medical instruments, and their use should be discontinued. Hand rubs are underutilised. GPs should implement Transmission Based Precautions to prevent airborne and droplet infections.

Development of Polymeric Resin Ion‐exchanger Based Chloride Ion‐selective Electrode for Monitoring Chloride Ion in Environmental Water

AbstractA chloride ion‐selective electrode (ISE) membrane was developed by using a copolymeric ion‐exchanger resin (trimethyl ethenyl quaternary ammonium chloride polystyrene‐divinylbenzene copolymer resin, TMEQAC PSDVB), the ionophore ({μ‐[4,5‐Dimethyl‐3,6‐bis(dodecyloxy)‐1,2‐phenylene]}bis(mercury chloride), ETH9033), the plasticizer (bis(2‐ethylhexyl) sebacate, DOS), and the membrane substrate (polyvinylchloride, PVC). At 25 °C, the electrode exhibited an ideal Nernstian response of 59.2 mV/decade with the linear calibration concentration range from 1.0 × 10−4‐1.0 × 10−2 M (r2 = 0.9930). The limit of detection was 2.45 ppm (6.9 × 10−2 mM) and the measurement response time was less than 10 seconds. The working temperature range of electrode was 10‐45 °C. The working pH range for chloride ion measurement was 2.0‐11.0. Among the various anions examined in this work, only I−, SCN−, and MnO4− ions show significant interference to the electrode measurement. The chloride ISE can be used at least 72 days. The determination of chloride ion content in three kinds of environmental water sample with the electrode method was accurate (92‐95%) and precise (RSD &lt; 4.4%) and did not show significance difference from the high‐performance liquid chromatography method.

Highly active catalysts for olefin metathesis in water

Preparation of novel, highly water soluble Ru complexes, which contain quaternary ammonium chloride tags is presented. The “on-site” quaternisation method can be used to obtain polar metathesis catalysts in an easy and efficient manner. Application profiles of three representative catalysts are described.

Antimicrobial Efficacies of Citra-Kill®, Disinfectant Solution against Salmonella Typhimurium and Brucella Ovis

Salmonellosis and brucellosis have caused a considerable danger of farmed animals and economic loss in animal farming industry. In this study, the disinfection efficacy of Citra-Kill<TEX>$^{(R)}$</TEX>, a commercial disinfectant, composed to quaternary ammonium chloride and citric acid was evaluated against S. typhimurium and Brucella ovis. A bactericidal efficacy test by broth dilution method was used to determine the lowest effective dilution of the disinfectant following exposure to test bacteria for 30 min at <TEX>$4^{\circ}C$</TEX>. Citra-Kill<TEX>$^{(R)}$</TEX> and test bacteria were diluted with distilled water (DW), hard water (HW) or organic matter suspension (OM) according to treatment condition. On OM condition, the bactericidal activity of Citra-Kill<TEX>$^{(R)}$</TEX> against S. typhimurium and Brucella ovis was lowered compared to that on HW condition. As Citra-Kill<TEX>$^{(R)}$</TEX> possesses bactericidal efficacy against animal pathogenic bacteria such as S. typhimurium and Brucella ovis, this disinfectant solution can be used to control the spread of animal bacterial diseases.

Quaternary ammonium salt substituted polyhedral oligosilsesquioxanes (POSSes) as structure directing agents in the generation of porous silica materials

AbstractThe sol-gel base catalysed hydrolytic polycondensations of tetramethoxysilane (TMOS) were studied in the presence of quaternary ammonium chloride substituted polyhedral oligosilsesquioxanes (POSSes): octa{3-[(2- hydroxyethyl)dimethylammonio]propyl chloride}octasilsesquioxane or octa[3-(noctyldimethylammonio) propyl chloride]octasilsesquioxane. Small amounts of these POSSes added to the sol-gel system markedly affected the morphology of the silica gel polycondensation products. The morphology was highly dependent on the POSS concentration. Amorphous mesoporous silica gels were obtained showing a high porosity and the surface area up to 615 m2g-1. Most of gels had a fairly large average pore diameters, 4-11 nm and pore volume 0.4-1.3 cm3g-1. TMOS having inserted hexamethyltrisiloxane chain, 1,1,1,7-tetramethoxyhexamethyltetra siloxane, (TMOSD3) in the mixture with TMOS was also used as the monomer in the sol-gel polycondensation; but obtained gels showed a low porosity.