Improvement of trickling biofilter purification performance on treating chlorobenzene in waste gases using surfactant

A laboratory-scale trickling biofilter column, filled with Raschig rings and inoculated with Pseudomonas putida （ATCC 1785） was used to ＇purify chlorobenzene contained waste gases. Sodium dodecyl sulfonate （SDS） was used to enhance the performance of trickling biofilter. Purification performance of the trickling biofilter was examined for chiorobenzene inlet concentration of 1.20,-5.04 g/m^3 at different EBRTs between 76N153 s. Without SDS addition, with simultaneous increase in chlorobenzene inlet loading rate and gas flow rate, 100% removal efficiency was achieved at EBRT of 109 s and inlet loadings below 5120 mg/m^3. Addition of SDS to nutrient solution led to improvement of trickling biofilter purification performance. By introducing 25 mg/L SDS, the removal efficiency was increased by 21% and elimination capacity up to 234 g/（m^3.h） was achieved at chlorobenzene inlet loading of 241 g/（m^3.h）. Although SDS concentration experienced a low rate reduction after continuous nutrient solution recirculation, this result has period little influence on trickling biofilter＇s removal efficiency in monitoring period.

Logically Sensing Aggregate Process and Discriminating SDS from Other Surfactants with the Assistance of BSA

An amphiphilic fluorescent probe, 3-dodecylamino dihydrogen imidazo[2,l-a]benz[de]isoquinolin-7-one （compound 3）, was used to sense the aggregate formation process of bovine serum albumine （BSA）, sodium dode- cyl sulfate （SDS） and their mixed system. The fluorescence intensity of 3 was significantly affected by the adding order of SDS and BSA, and SDS can be distinguished from other surfactants with the aid of BSA, but only when 3 is allowed to interact with BSA first. The results revealed that compound 3 is preferentially sited in the hydrophobic region of BSA, and thermodynamically in SDS-BSA mixed aggregate. Sodium phosphate buffer solution （PBS） and BSA played important but distinct roles in distinguishing SDS micelle from the others.

Validation of Metformin Hydrochloride in Human Plasma by HPLC-Photo Diode Array （PDA） for Application of Bioequivalence Study

A sensitive and specific high performance liquid chromatography （HPLC） method was developed and validated for the simultaneous determination of metformin hydrochloride （HCI） in human plasma. The HPLC method consists of isocratic eluation with a mixture of 60% buffer （10 mM sodium dihyrogenphosphate-10 mM sodium dodecyl sulphate） and 40% acetonitrile with final pH 7.0 with flow rate of 1.0 mL/min on a Kromasil~ Akzo Nobel RP-18 （4.6 mm ID ~ 250 mm, 5 ~tm） column at an ambient temperature. Photo diode array detection was performed in program mode at 234 rim. The analyte and diazepam as internal standard （IS） were extracted from plasma using 10% trichloroacetic acid. The assay was linear over the therapeutic concentration range of 20-2,500 ng/mL for metformin HCI with correlation coefficient of r = 0.9999. Limit of quantitation was 20 ng/mL. The results obtained for intraJinter day accuracy and precision complied very well with the generally accepted criteria for bio-analytical assay. The method was applied to bioequivalence （BE） study of metformin HCI in healthy Indonesian volunteers after treatment with 750 mg XR metformin HCI. This BE study shows that the two formulations are equivalent so that they were therapeutically interchangeable for each other.

The Effect of Audit Objectives on Audit Quality Why is There Little Disclosure of Significant Deficiencies in Japanese Internal Control Audits？

Many prior research findings indicate that audit quality differs between the Big 4 and non-Big 4 audit firms using an indicator variable. However, most previous research focuses on only outcome measures, such as audit fees, going concern reports, and non-audit services. This study investigates audit quality differentiation between the Big 4 and non-Big 4 audit firms hypothesis from an audit objective point of view. One of the material objectives of Japanese internal control audit institutions is to facilitate assessment and improvement of internal controls by corporations themselves. The findings of this study indicate that the Big 4 audit firms accomplish this objective better than non-Big 4 audit firms. Consequently, most Big 4 clients do not disclose significant deficiencies （SDs）, implying that they improve the quality of internal controls through internal controls auditing. This paper concludes that Big 4 firms produce a higher audit quality level than non-Big 4 firms, and this quality difference iS related to how an audit objective is interpreted and implemented.

Determination of Anionic Surfactants in Environmental Water Samples Using Fluorescence Enhancement Method Based on Fe_3O_4@PAA-RB Fluorescent Nanoparticles

[ Objective] The study aims at developing a novel fluorescence enhancement method to determine anionic surfactants. [ Method] Based on Fe3O4 @ PAA-RB fluorescent nanoparticles as fluorescent probes, we have developed a novel fluorescence enhancement method for the determi- nation of an anionic surfactant sodium dodecyl sulfate （SDS） through the gradual optimization of experiment conditions. [ Result] Under the opti- mum conditions, the extent of fluorescence enhancement is directly proportional to SDS concentration varying from 0.5 to 16.0 μmol/L, and the de- tection limit reaches 0.051 μmol/L. The relative standard deviation （RSD） for 4.0 μmol/L SDS is 3.3% （ n =6）. The proposed method has been successfully applied to the determination of SDS in environmental water samples, with recovery of 96.3% -105.5%. E Conclusion] The novel fluo- rescence enhancement method is not only simple and rapid, but also has avoided using tedious solvent-extraction and toxic organic solvents.

A Time/Space Separation Based 3D Fuzzy Modeling Approach for Nonlinear Spatially Distributed Systems

Spatially distributed systems （SDSs） are usually infinite-dimensional spatio-temporal systems with unknown nonlinearities. Therefore, to model such systems is difficult. In real applications, a low-dimensional model is required. In this paper, a time/space separation based 3D fuzzy modeling approach is proposed for unknown nonlinear SDSs using input-output data measurement. The main characteristics of this approach is that time/space separation and time/space reconstruction are fused into a novel 3D fuzzy system. The modeling methodology includes two stages. The first stage is 3D fuzzy structure modeling which is based on Mamdani fuzzy rules. The consequent sets of 3D fuzzy rules consist of spatial basis functions estimated by Karhunen-Love decomposition. The antecedent sets of 3D fuzzy rules are used to construct temporal coefficients. Going through 3D fuzzy rule inference, each rule realizes time/space synthesis. The second stage is parameter identification of 3D fuzzy system using particle swarm optimization algorithm. After an operation of defuzzification, the output of the 3D fuzzy system can reconstruct the spatio-temporal dynamics of the system. The model is suitable for the prediction and control design of the SDS since it is of low-dimension and simple nonlinear structure. The simulation and experiment are presented to show the effectiveness of the proposed modeling approach.

Sodium dodecyl sulfate sensitized electrochemical method for sub-picomole level determination of topotecan hydrochloride at a novel disposable electrode

A sub-picomole level topotecan hydrochloride determination method was first proposed using sodium dodecyl sulfate (SDS) as a sensitized reagent at a novel disposable electrode (an improved wax-impregnated graphite electrode).The effects of different kinds of surfactants on the electrochemical response to topotecan hydrochloride were examined.The results indicate the electrochemical signal was apparently improved by SDS.At optimal conditions,the oxidative peak current increased linearly with the logarithm of concentrations for topotecan hydrochloride in the ranges of 2.0 × 10-12 to 1.0 × 10-11 mol/L and 8.0 × 10-11 to 8.0 × 10-10 mol/L with a detection limit of 6.4 × 10-13 mol/L.The proposed method could be applied in determining topotecan hydrochloride in urine.

Chitosan-collagen/organomontmorillonite scaffold for bone tissue engineering

A novel composite scaffold based on chitosan-collagenlorganomontmo- rillonite （CS-COL/OMMT） was prepared to improve swelling ratio, biodegradation ratio, biomineralization and mechanical properties for use in tissue engineering applications. In order to expend the basal spacing, montmorillonite （MMT） was modified with sodium dodecyl sulfate （SDS） and was characterized by XRD, TGA and FTIR. The results indicated that the anionic surfactants entered into interlayer of MMT and the basal spacing of MMT was expanded to 3.85 nm. The prepared composite scaffolds were characterized by FTIR, XRD and SEM. The swelling ratio, biodegradation ratio and mechanical properties of composite scaffolds were also studied. The results demonstrated that the scaffold decreased swelling ratio, degradation ratio and improved mechanical and biomineralization properties because of OMMT.