bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficiency Increase by Insertion of Electrodeposited CuSCN Layer into ITO/Organic Solid Interface in Bulk Hetero-junction Solar Cells Consisting of Polythiophene and Fullerene
Authors: Takahashi Kohshin , Suzaka Syouko , Sigeyama Yasunori , Yamaguchi Takahiro , Nakamura Jun-ichi , Murata Kazuhiko
Published: May 2007

When an electrodeposited CuSCN thin film was inserted into the interface of ITO/P3HT:PCBM blended solid film (P3HT: regioregular poly(3-hexylthiophene), PCBM: soluble [6,6]-phenyl C61 buttyric acid methyl ester) in ITO/P3HT:PCBM/Al sandwich-type solar cells, the cell performance was remarkably improved, resulting in 2.5% of energy conversion yield under the irradiation of AM 1.5–100 mW/cm2 simulated sunlight.
Di(tert-butyl)[(pyren-1-yl)methoxy]silyl Chloride: Synthesis and Application in Purification of Synthetic Deoxyribonucleotides
Authors: Mishra Roli , Misra Krishna
Published: May 2007

Di(tert-butyl)[(pyren-1-yl)methoxy]silyl chloride reacts selectively with the 5′-hydroxy groups in deoxynucleosides and this can be removed under conditions which do not affect other commonly used acid or base labile protecting groups, yet it, is stable to phosphorylation conditions. While incorporated terminally at 5′-OH of the long sequence viz., 26-mer, this group is also helpful in subsequent purification by HPLC as well as PAGE. Fluorescence properties of these sequences were studied to find the suitability of the approach.
Novel Hexagonally Ordered Nitrogen-doped Mesoporous Carbon from SBA-15/Polyaniline Nanocomposite
Authors: Vinu Ajayan , Srinivasu Pavuluri , Mori Toshiyuki , Sasaki Toshio , Asthana Anjana , Ariga Katsuhiko , Hishita Shunichi
Published: May 2007

A novel nitrogen-doped mesoporous carbon with well-ordered two-dimensional (2D) structure has been successfully prepared for the first time using aniline as a source for both carbon and nitrogen, and SBA-15 as a template. The above material has been unambiguously characterized by various sophisticated techniques such as XRD, HRTEM, XPS, and nitrogen adsorption. The obtained material possesses very high surface area, pore volume, and uniform pore size distribution. The XPS and CHN analysis revealed that nitrogen atom is successfully doped on the mesoporous carbon walls.
Direct Electrochemistry of Myoglobin in MnO2 Nanosheet Film
Authors: Xiao Han , Chen Xu , Ji Liyan , Zhang Xiong , Yang Wensheng
Published: May 2007

A continuous myoglobin/MnO2 nanosheet (derived via the delamination of layered manganese oxide) film was prepared by a simple method for the first time. The direct electrochemistry of myoglobin immobilized in the film was investigated using electrochemical methods.
Programmed Formation of Nanogels via a Radical Crossover Reaction of Complementarily Reactive Diblock Copolymers
Authors: Amamoto Yoshifumi , Higaki Yuji , Matsuda Yasuhiro , Otsuka Hideyuki , Takahara Atsushi
Published: May 2007

By heating two types of diblock copolymers with complementarily reactive alkoxyamine units in the side chains, nanogels were formed as a result of a radical crossover reaction of the alkoxyamine units. The transformation from the diblock copolymers to nanogels and their absolute molecular weight were obviously dependent on reaction concentrations and the mixing ratio of two types of diblock copolymers.
Synthesis and Crystal Structure of a Zirconium Complex Containing Germanolato Ligands and Its Catalytic Activity for Ethylene Polymerization
Authors: Goto Kei , Shimo Isao , Okumura Tomoko , Kawashima Takayuki
Published: May 2007

A dialkylbis(germanolato)zirconium complex was synthesized by taking advantage of a novel bowl-shaped germanol as the ligand source, presenting the first example of a zirconium complex containing germanolato ligands. The bis(germanolato) complex as well as the analogous bis(silanolato) complex was found to exhibit catalytic activity for ethylene polymerization.
Activation of Double-stranded DNA by One pcPNA Strand for Its Site-selective Scission with CeIV/EDTA
Authors: Aiba Yuichiro , Yamamoto Yoji , Komiyama Makoto
Published: May 2007

In the presence of only one strand of pseudo-complementary PNA (pcPNA), double-stranded DNA was selectively hydrolyzed by CeIV/EDTA (EDTA = ethylenediamine-N,N,N′,N′-tetraacetate) at target site. Compared with previously reported artificial restriction DNA cutters using two pcPNA strands, the present cutters are simple and promising for various applications.
Thermochromism of Polydiacetylene with a Hysteresis Loop in the Solid State and in Solution
Authors: Dei Satoshi , Matsumoto Akikazu
Published: May 2007

Partly crystalline polydiacetylene 1, which is soluble in many organic solvents at room temperature, was prepared by the solid-state polymerization of 4-methoxybenzyl 10,12-pentacosadiynoate. We found a reversible change in the UV–vis absorption spectrum of 1 in a solid film, polymer matrix, and solution with a hysteresis loop as a function of temperature.
An Alternative Electron Donor for Hyphomicrobium Copper-containing Nitrite Reductase
Authors: Nojiri Masaki , Agatahama Atsushi , Kobayashi Ryosuke , Yamaguchi Kazuya , Suzuki Shinnichiro
Published: May 2007

Cu-containing nitrite reductase from Hyphomicrobium denitrificans catalyzes the reduction of nitrite to nitric oxide by an electron from a specific electron donor protein, cytochrome c550. However, we have recently found that another periplasmic soluble cytochrome c, cytochrome cL, also donates an electron to this enzyme. The detailed electron-transfer mechanism was investigated kinetically.
Creation of Discrete Silver(I) Coordination Compounds with Nonbridging Chlorides by the Use of Mono(d-penicillaminato)cobalt(III) Metalloligand
Authors: Mitsunaga Seiichi , Tamura Motoshi , Igashira-Kamiyama Asako , Konno Takumi
Published: May 2007

The reactions of the ΛD or ΔD isomer of [Co(d-Hpen-N,S)(en)2](ClO4)2 (1; d-H2pen = d-penicillamine) with AgNO3 in water, followed by the addition of NaCl and HCl, led to the formation of discrete CoIIIAgI dinuclear complexes, ΛD- or ΔD-[AgCl3{Co(d-Hpen-N,S)(en)2}]. A similar reaction using a 1:1 mixture of the ΛD and ΔD isomers of 1, followed by the addition of NaCl, afforded a CoIII2AgI2 tetranuclear complex, ΛDΔD-[Ag2Cl4{Co(d-Hpen-N,S)(en)2}2]2+.
Rod-shaped Oligophenyleneethynylenes Modified by Donor and Acceptor Groups in a Block Manner: Synthesis and Light-emitting Characteristics
Authors: Ochi Takanori , Yamaguchi Yoshihiro , Kobayashi Shigeya , Wakamiya Tateaki , Matsubara Yoshio , Yoshida Zen-ichi
Published: May 2007

Highly efficient blue light emmitters represented by BL-5 (Φf = 0.96, λem = 455 nm in CHCl3) and BL-8 (Φf = 0.98, λem = 464 nm in CHCl3) are created by block modification of oligophenylene ethynylenes with donor and acceptor groups. A linear relationship with positive slope between Φf and the movability of the energetically equivalent dipolar structure unit is found for the first time.
Surgical training in Sweden
Authors: Påhlman Lars
Published: May 2007

Introduction Sweden has six medical schools, from which 1,000 students graduate yearly. The programme in these schools is broadly identical and after 5.5 years at university the students do not receive a specific academic title, just a 'doctor's examination' (in Swedish). A graduate cannot, however, work as a physician after those 5.5 years. A further 18–24 months of internship are obligatory; all then work as doctors within surgery, internal medicine, psychiatry and finally as general practitioners. In total 7–7.5 years of study (with the last two years as an intern) are required, which include a final theoretical examination in surgery, internal medicine and psychiatry. Having passed those examinations the doctor receives certification from the Swedish National Board of Health and may work as a 'board-certified doctor'.
Engaging a Pariah: Human Rights Training in Burma/Myanmar
Authors: Kinley David , Wilson Trevor
Published: May 2007

The people of Burma/Myanmar have suffered for two generations under military dictatorships. Their economy, legal and social orders, cultural diversity, and political freedoms have all steadily declined during that time. The country's human rights record is considered by many to be one of the worst world-wide. In the West, responses have ranged from diplomatic condemnation, to the imposition of economic sanctions, and to the withdrawal of aid and international cooperation. Countries in the region, on the other hand, have been typically less robust, more accepting of assertions of sovereign rights and concerned to promote engagement and dialogue rather than isolation and punishment. Neither approach appears to have had any discernable impact on the attitude of Myanmar's military government or on the plight of its people. Aung San Suu Kyi remains under house arrest, her pro-democracy party banned, and its members persecuted; the rule of law is non existent, and the once flourishing economy is in terminal decline. New strategies to break the impasse are now being contemplated in both the West (more conditional engagement) and the East (more strident conditionality). This article analyzes a controversial Australian human rights initiative that ran in Myanmar from 2000 to 2003, which might be considered a forerunner to these new "third way" approaches. The article describes the objectives, nature, composition and implementation of the program; it assesses its advantages and disadvantages, its risks and potential, and explores some of the criticisms and praise the program engendered. It also provides a detailed backdrop against which one might draw some tentative lessons in terms of the protection and promotion of human rights in both the specific context of Myanmar, and also, by implication, in the global community's approach to intransigent, pariah states.
The protease domain of procollagen C-proteinase (BMP1) lacks substrate selectivity, which is conferred by non-proteolytic domains
Authors: Wermter Carsten , Höwel Markus , Hintze Vera , Bombosch Bettina , Aufenvenne Karin , Yiallouros Irene , Stöcker Walter
Published: May 2007

Procollagen C-proteinase (PCP) removes the C-terminal pro-peptides of procollagens and also processes other matrix proteins. The major splice form of the PCP is termed BMP1 (bone morphogenetic protein 1). Active BMP1 is composed of an astacin-like protease domain, three CUB (complement, sea urchin Uegf, BMP1) domains and one EGF-like domain. Here we compare the recombinant human full-length BMP1 with its isolated proteolytic domain to further unravel the functional influence of the CUB and EGF domains. We show that the protease domain alone cleaves truncated procollagen VII within the short telopeptide region into fragments of similar size as the full-length enzyme does. However, unlike full-length BMP1, the protease domain does not stop at this point, but degrades its substrate completely. Moreover, the protease domain cleaves other matrix proteins such as fibronectin, collagen I and collagen IV, which are left intact by the full-length enzyme. In addition, we show for the first time that thrombospondin-1 is differently cleaved by both BMP1 and its catalytic domain. In summary, our data support the concept that the C-terminal domains of BMP1 are important for substrate recognition and for controlling and restricting its proteolytic activity via exosite binding.
Characterization of peptidyl-tRNA hydrolase encoded by open reading frame Rv1014c of Mycobacterium tuberculosis H37Rv
Authors: Bal Naresh C. , Agrawal Himanshu , Meher Akshaya K. , Arora Ashish
Published: May 2007

The enzyme peptidyl-tRNA hydrolase (Pth, EC 3.1.1.29) is essential for the viability of bacteria. The ORF Rv1014c of Mycobacterium tuberculosis H37Rv, designated as the mtpth gene, was cloned and over-expressed and the product was purified. Generation of polyclonal antibodies against the purified recombinant protein, termed MtPth, facilitated detection of endogenously expressed MtPth in M. tuberculosis H37Rv cell lysate. MtPth could release diacetyl-[3H]-lysine from diacetyl-[3H]-lysyl-tRNALys with Michaelis-Menten kinetic parameters of K
m=0.7±0.2 μM and k
cat=1.22±0.2 s-1. Transformation of a pTrc99c/mtpth vector allowed the growth of E. coli thermosensitive Pth(ts) mutant strain AA7852 at the non-permissive temperature of 42°C, demonstrating the in vivo activity of MtPth. In addition, at 39°C, over-expression of MtPth in AA7852 cells allowed the cells to remain viable in the presence of up to 200 μg/ml erythromycin. A 3D fold based on NMR and a structural model based on the E. coli Pth crystal structure were generated for MtPth. The essential nature of conserved active-site residues N12, H22 and D95 of MtPth for catalysis was demonstrated by mutagenesis and complementation in E. coli mutant strain AA7852. Thermal and urea/guanidinium chloride (GdmCl)-induced unfolding curves for MtPth indicate a simple two-state unfolding process without any intermediates.
Mid-region parathyroid hormone-related protein (PTHrP) and gene expression of MDA-MB231 breast cancer cells
Authors: Sirchia Rosalia , Luparello Claudio
Published: May 2007

We have previously shown that PTHrP(38–94) amide restrains growth and invasion in vitro, causes striking toxicity and accelerates death of some breast cancer cell lines, the most responsive being MDA-MB231, for which tumorigenesis was also attenuated in vivo. We have also demonstrated that mid-region PTHrP gains access to the nuclear compartment of these cells and displays DNA-binding properties in vitro by recognizing targets in both cellular chromatin and isolated oligonucleotides. Here, we examined whether PTHrP(38–94) amide was able to modulate gene expression of MDA-MB231 cells, employing a combination of conventional, differential display and semi-quantitative multiplex PCR techniques. The results obtained provide first evidence that PTHrP(38–94) amide can affect gene expression in tumor cells, identifying A4-differentiation protein/PLP2 as up-regulated, and HOX7/MSX1, COX6C, FZD6, OXR1 and TMCO4 as down-regulated genes in treated cells, and suggest that the cytotoxic activity of the peptide can be ascribed, at least in part, to such transcriptional reprogramming.
Clinical chemistry reference database for Wistar rats and C57/BL6 mice
Authors: Boehm Olaf , Zur Berndt , Koch Alexander , Tran Nguyen , Freyenhagen Rainer , Hartmann Matthias , Zacharowski Kai
Published: May 2007

Clinical chemistry data are decisive for evaluating altered organ function or damage in experimental animals. Few publications provide reliable clinical chemistry reference intervals, and analytical methods are often not described. Here, we investigated common clinical chemistry values in adult male and female Wistar rats and C57/BL6 mice (n=30/group). Blood samples were taken and analysed for electrolytes, substrates, metabolites and enzymes. In addition, we investigated cystatin C, an important marker of glomerular dysfunction. All data were obtained using commercially available kits frequently employed in most clinical chemistry laboratories and compared with data from other studies, as well as with human data. Significant gender-specific differences were observed in rats (electrolytes, retention parameters and transaminases) and in mice (cholesterol, glucose). High variability was noted for sodium, potassium, glucose, creatine kinase, lactate dehydrogenase and transaminase levels. Both rodent species showed markedly higher α-amylase activity than humans. This report demonstrates significant differences between genders for many analytes in rats and for fewer parameters in mice. Some reference values displayed major discrepancies between rodents and humans.
Factors predicting the perceived effectiveness of politicians' use of humor during a debate
Authors: Bippus Amy
Published: May 2007

Prior research on humor in the political context has focused primarily on people's reactions to humor about politicians in the form of cartoons or jokes, or on specific politicians' use of humor as a rhetorical strategy. This study provides an empirical test of audience perceptions of the effectiveness of a politician's use of humor during a political debate. Data were collected during the 2004 election cycle; respondents were told a candidate had made a humorous remark during a recent congressional campaign debate. Party affiliation of the candidate and the target of the humor (himself vs. his opponent) were counterbalanced. The results indicated that self-deprecating humor was rated as more effective, and both Democrats and Republicans saw humor from a Democratic candidate as more effective than from a Republican. Being of the same versus opposite party of the candidate did not affect respondents' attributions of the candidate's motives for using humor or its overall effectiveness. Overall, the biggest predictor of perceived effectiveness was respondents' assessment of the quality (timing and funniness) of the humor.
Regional humor differences in the United States: Implications for management
Authors: Romero Eric J , Alsua Carlos J , Hinrichs Kim T , Pearson Terry R
Published: May 2007

This paper is an exploratory study examining humor differences among four regions of the United States and the managerial implications of such differences. The results indicate significant differences between the regions regarding affiliative and self-defeating humor, the creation and performance of humor, the use of humor in coping and in social situations, and attitudes toward humor. Managerial implications for researchers and practitioners are discussed.
Relative performance of duckweed ponds and rock filtration as advanced in-pond wastewater treatment processes for upgrading waste stabilisation pond effluent: a pilot study
Authors: Short M.D. , Cromar N.J. , Nixon J.B. , Fallowfield H.J.
Published: May 2007

An experimental pilot plant was operated over a five month period to assess the relative treatment performances of: a duckweed (DW) pond; a rock filter (RF); and an open pond (OP); for the upgrading of final WSP effluent prior to reuse applications. Each pilot treatment system consisted of three identical ponds arranged in three parallel series, each fed a continuous flow of wastewater from the local Bolivar treatment plant. Light penetration profiling for the DW and OP systems revealed some 55% greater light attenuation capacity for DW ponds compared to the OP system. Results showed a significantly elevated performance capacity for the RF treatment with respect to BOD5, SS, turbidity and NH4-N removal, but equal treatment performances for algal (chlorophyll) removal. No significant performance differences were evident between the DW and OP treatments for any of the monitored parameters. Soluble reactive phosphorus, faecal coliform and E. coli removals were similar for all pilot treatment systems. Rock filters not only demonstrated an enhanced performance capacity in terms of removal of loaded parameters, but also showed greater reliability of performance and produced a consistently higher quality final effluent. Rock filters demonstrated greater potential over both DW and OP systems for the upgrading of WSP effluent prior to reuse application.
Modelisation of the contribution of sediments in the treatment process case of aerated lagoons
Authors: Jupsin H. , Vasel J.-L.
Published: May 2007

In aerated lagoons and even more in stabilization ponds the specific power (W/m3) is not high enough to maintain all the suspended solids in suspension. Some part of the suspended solids (including biomass) settles directly into the reactor and not in the final settling pond. The gradual accumulation of those sediments on the pond bottom affects performance by reducing the pond volume and shortening the Hydraulic Residence Time. However, the role played by these deposits is not restricted to such a physical effect. Far from being inert sediments they are also an important oxygen sink that must be taken into account when designing aerator power and oxygen supply, for example. On the other hand, under aerobic conditions, the upper layer of sediments may contribute to the treatment as a biofilm compartment in the reactor. In aerated lagoon systems another process contributes to the interaction of deposits and the liquid phase: the operating (often sequencing) of aerators may induce a drastic resuspension of deposits. In a 3,000 m3 aerated lagoon we evaluated that 3 tons of deposits were resuspended when aerators were started. Due to those processes we consider that a mathematical model of an aerated lagoon or of a stabilization pond has to take into account the contribution (positive and negative aspects) of deposits in the process. In this paper we propose a model for sediments including production but also biological processes. Simulations of the aerated lagoon with or without the “sediment compartment” demonstrate the effect and the importance of this compartment on the process. Of course a similar approach could be used for facultative or even maturation ponds. The next step would be to include anaerobic activities in the bottom layer.
Coarse filters for pond effluent polishing: comparison of loading rates and grain sizes
Authors: von Sperling M. , de Andrada J.G.B. , de Melo Júnior W.R.
Published: May 2007

A system comprising a UASB reactor, shallow polishing ponds and shallow coarse filters, treating actual wastewater from the city of Belo Horizonte, Brazil, has been evaluated. The main focus of the research was to compare grain sizes and hydraulic loading rates in the coarse filters. Two filters operating in parallel were investigated, with the following grain sizes: Filter 1: 3 to 10 cm; Filter 2: 8 to 20 cm. Two hydraulic loading rates were tested: 0.5 and 1.0 m3/m3.d. The filter with the lower rock size had a better performance than the filter with the larger rock size in the removal of SS and, as a consequence, BOD and COD. A better performance was obtained with the hydraulic loading rate of 0.5 m3/m3.d, as compared to the rate of 1.0 m3/m3.d. The effluent quality during the period with the lower loading rate was very good for discharge into water bodies or for agricultural reuse (median effluent concentrations from Filter 1: BOD: 20 mg/L; COD: 106 mg/L; SS: 28 mg/L; E. coli: 528 MPN/100 mL).
Reliability analysis of stabilisation pond systems
Authors: Oliveira S.M.A.C. , von Sperling M.
Published: May 2007

This article presents a reliability analysis of 116 full-scale pond systems in Brazil, comprising 73 primary facultative ponds and 43 anaerobic–facultative pond systems. A methodology developed by Niku et al. (1979) is used for the determination of the coefficients of reliability, in terms of the compliance of effluent BOD, COD, TSS and FC to discharge standards or effluent quality targets. The design concentrations necessary to meet the prevailing discharge standards and the expected compliance percentages have been calculated from the coefficients of reliability obtained. The results showed that few units, under the observed operating conditions, would be able to present reliable performances in terms of compliance with the analyzed standards. For the four constituents (BOD, COD, TSS and FC) and both systems (facultative ponds and anaerobic-facultative systems), the variability of the effluent quality was very large, leading to a high variability of the coefficient of variation (CV) and the coefficient of reliability (COR). The effluent quality from the facultative ponds showed a larger distance to both the desired values and the discharge standard values, compared with the anaerobic–facultative systems.
Effect of baffles on nitrification in aerated facultative lagoons in a cold climate
Authors: Houweling D. , Chazarenc F. , Leduc R. , Comeau Y.
Published: May 2007

Tracer studies performed in two aerated facultative lagoons indicate some bypass and an overall hydraulic regime close to completely-mixed. Results were used to calibrate a hydraulic model based on the tanks-in-series approach. The hydraulic model was combined with a simple “death-regeneration” biokinetic model to simulate seasonal nitrification as observed over a three year period. Modifications were made to the hydraulic model to represent the effect of baffle installations to 1) eliminate bypass and 2) impose a plug-flow regime. Simulation results indicate there is some gain to eliminating bypass but that imposing a plug-flow regime would increase biomass washout rates and hinder nitrification.
RTD (residence time distribution) predictions in large mechanically aerated lagoons
Authors: Stropky D. , Pougatch K. , Nowak P. , Salcudean M. , Pagoria P. , Gartshore I. , Yuan J.
Published: May 2007

Mechanically aerated lagoons (used for wastewater treatment in the pulp and paper industry) are typically very large (>500,000 m3) and have complex three-dimensional fluid flow patterns due to mechanical agitation, sludge accumulation, internal baffling, and confined inlet/outlet flow channels. RTD data is frequently used for evaluation of hydraulic performance. however, obtaining accurate data with traditional dye measurements is a difficult and time-consuming process. Moreover, the mixing impact of factors such as aerator positions, sludge accumulation, and internal baffles would require a significant and costly number of local field measurements. Recent applications of CFD to mechanically aerated lagoons have helped engineers to understand the complex flow interactions. This paper provides a practical method for the evaluation of the hydraulic performance of large mechanically aerated lagoons using CFD. A method, based on random-walk Lagrangian particle tracking, has been developed to significantly shorten the computational time needed to produce RTD curves for these lagoons. Comparison of the particle method with the more conventional scalar transport yields excellent results. These methods allow wastewater engineers to combine their existing knowledge and expertise with the established power of CFD. The results quantify the hydraulic impact of different inlet/outlet configurations, aerator configurations, influent flow rates, and bottom sludge profiles.
Nitrogen removal in maturation ponds: tracer experiments with 15N-labelled ammonia
Authors: Camargo Valero M.A. , Mara D.D.
Published: May 2007

A primary maturation pond (M1) was spiked with labelled ammonium chloride (15NH4Cl) to track ammonium transformations associated with algal uptake and subsequent sedimentation. Conventional sampling based on grab samples collected from M1 influent, water column and effluent, and processed for unfiltered and filtered TKN, ammonium, nitrite and nitrate, found low total nitrogen removal (8%) and high ammonium nitrogen removal (90%). Stable isotope analysis of 15N from suspended organic and ammonium nitrogen fractions in M1 effluent revealed that labelled ammonium was mainly found in the organic fraction (69% of the 15N recovered), rather than the inorganic fraction (5%). Algal uptake was the predominant pathway for ammonia removal, even though conditions were favourable for ammonia volatilization (8.9 < pH <10.1 units, 15.2 < temperature <18.8 °C). Total nitrogen was removed by ammonia volatilization at 15 g N/ha d (3%), organic nitrogen sedimentation at 105 g N/ha d (20%), and in-pond accumulation due to algal uptake at 377 g N/ha d (71%). Algal uptake of ammonium and subsequent sedimentation and retention in the benthic sludge, after partial ammonification of the algal organic nitrogen, is thus likely to be the dominant mechanism for permanent nitrogen removal in maturation ponds during warm summer months in England.
Nitrogen removal via ammonia volatilization in maturation ponds
Authors: Camargo Valero M.A. , Mara D.D.
Published: May 2007

A simple apparatus was designed to collect ammonia gas coming out from waste stabilization ponds (WSP). The apparatus has a capture chamber and an absorption system, which were optimized under laboratory conditions prior to being used to assess ammonia volatilization rates in a pilot-scale maturation pond during summer 2005. Under laboratory conditions (water temperature = 17.1 °C and pH = 10.1), the average ammonia volatilization rate was 2,517 g NH3-N/ha d and the apparatus absorbed 79% of volatilized ammonia. On site, the mean ammonia volatilization rate was 15 g N/ha d, which corresponds to 3% of the total nitrogen removed (531 g N/ha d) in the maturation pond studied. A net nitrogen mass balance showed that ammonia volatilization was not the most important mechanism involved in either total nitrogen or ammonia removal. Nitrogen fractions (suspended organic nitrogen, soluble organic nitrogen, ammonia, nitrite and nitrate) from the M1 influent and effluent showed that ammonia is removed by biological (mainly algal) uptake and total nitrogen removal by sedimentation of dead algal biomass.
Sewage reuse for aquaculture after treatment in oxidation and duckweed pond
Authors: Ghangrekar M.M. , Kishor N. , Mitra A.
Published: May 2007

The benefits of treating sewage by pond systems offer, through a simple and low-cost technology, social and commercial benefits, from the waste raw materials. The objective of this work was to demonstrate an effective treatment of the sewage by using natural treatment systems, and use of treated wastewater for aquaculture. The study was conducted for the sewage generated from the IIT Kharagpur campus. After characterization of the sewage, laboratory scale experiments were conducted for treatment using oxidation pond and duckweed pond. Survival and growth of fishes were observed in the experimental ponds using treated sewage. Based on the experimental results, full-scale treatment plant was designed to meet the aquaculture water quality. From the economics of the proposed full-scale plant, and utilization of the treated sewage for aquaculture, it is estimated that, the amount of Rs. 20,0000 can be generated every year. This amount recovered from the aquaculture will be more than the operating cost of the treatment plant, hence, making the operation of sewage treatment plant self sufficient. Use of a UASB reactor as the first stage treatment before sewage passes to the oxidation pond, can be a more attractive alternative because of less land requirement as compared to the oxidation pond alone, and additional land can be made available for aquaculture to increase revenue.
Nitrification in bulk water and biofilms of algae wastewater stabilization ponds
Authors: Babu M.A. , Mushi M.M. , van der Steen N.P. , Hooijmans C.M. , Gijzen H.J.
Published: May 2007

Nitrogen removal in wastewater stabilization ponds is poorly understood and effluent monitoring data show a wide range of differences in ammonium. For effluent discharge into the environment, low levels of nitrogen are recommended. Nitrification is limiting in facultative wastewater stabilization ponds. The reason why nitrification is considered to be limiting is attributed to low growth rate and wash out of the nitrifiers. Therefore to maintain a population, attached growth is required. The aim of this research is to study the relative contribution of bulk water and biofilms with respect to nitrification. The hypothesis is that nitrification can be enhanced in stabilization ponds by increasing the surface area for nitrifier attachment. In order to achieve this, transparent pond reactors representing water columns in algae WSP have been used. To discriminate between bulk and biofilm activity, 5-day batch activity tests were carried out with bulk water and biofilm sampled. The observed value for Rnitrbulk was 2.7 × 10−1 mg-N L−1 d−1 and for Rbiofilm was 1,495 mg-N m−2 d −1. During the 5 days of experiment with the biofilm, ammonia reduction was rapid on the first day. Therefore, a short-term biofilm activity test was performed to confirm this rapid decrease. Results revealed a nitrification rate, Rbiofilm, of 2,125 mg-N m−2 d−1 for the first 5 hours of the test, which is higher than the 1,495 mg-N m−2 d−1, observed on the first day of the 7-day biofilm activity test. Rbiofilm and Rnitrbulk values obtained in the batch activity tests were used as parameters in a mass balance model equation. The model was calibrated by adjusting the fraction of the pond volume and biofilm area that is active (i.e. aerobic). When assuming a depth of 0.08 m active upper layer, the model could describe well the measured effluent values for the pond reactors. The calibrated model was validated by predicting effluent Kjeldahl nitrogen of algae ponds in Palestine and Colombia. The model equation predicted well the effluent concentrations of ponds in Palestine.
Influence of CO2 scrubbing from biogas on the treatment performance of a high rate algal pond
Authors: Heubeck S. , Craggs R.J. , Shilton A.
Published: May 2007

Biogas produced by anaerobic treatment of wastewater can be collected and used for power generation. However, the biogas may require scrubbing to prevent corrosion by H2S and to improve engine efficiency by reducing the CO2 content. HRAP can be used to scrub biogas during the daytime when they are carbon-limited and have high pH. This study investigates the influence of the carbon dioxide addition from biogas scrubbing on high rate algal pond wastewater treatment performance (in terms of BOD, NH4-N, DRP and E. coli removal) and algal production (growth and species composition). Batch culture experiments were conducted in laboratory microcosms (2 L) and outside mesocosms (20 L). Results indicate that CO2 addition and reduced culture pH increased algal production and nutrient assimilation, decreased high pH mediated nutrient removal processes (phosphate precipitation and ammonia volatilisation), but had little influence on the ability of the culture to remove filtered BOD5. Disinfection, as indicated by E.coli removal; was reduced, however, further research on virus removal, which is not affected by culture pH, is required. These preliminary findings indicate the potential to scrub CO2 from biogas using high rate pond water without decreasing the effectiveness of wastewater treatment and enabling increased recovery of wastewater nutrients as algal biomass.
Nitrogen removal in recirculated duckweed ponds system
Authors: Benjawan L. , Koottatep T.
Published: May 2007

Duckweed-based ponds (DWBPs) have the potential for nitrogen (N) removal from wastewater; however, operational problems such as duckweed die-off regularly occur. In this study, effluent recirculation was applied to the DWBPs to solve the above problem as well as to investigate N removal mechanisms. Two pilot scale recirculated DWBPs were employed to treat municipal wastewater. The average removal efficiencies for TN, TKN and NH4-N were 75%, 89% and 92%, respectively at TN loading of 1.3 g/m2.d and were 73%, 74% and 76%, respectively at TN loading of 3.3 g/m2.d. The effluent of the system under both operational conditions had stable quality and met the effluent standard. Duckweed die-off was not observed during the study, which proves the system stability and effluent recirculation which is thought to be a reason. N-mass balance revealed that nitrification–denitrification and duckweed uptake play major roles in these recirculated DWBPs. The rates of nitrification–denitrification were increased as TN loading was higher, which might be an influence from an abundance of N and a suitable condition. The rates of N uptake by duckweed were found similar and did not depend on the higher TN loading applied, as the duckweed has limited capacity to assimilate it.
Three dimensional fluorescent spectroscopy analysis for the evaluation of organic matter removal from industrial estate wastewater by stabilization ponds
Authors: Musikavong C. , Wattanachira S. , Nakajima F. , Furumai H.
Published: May 2007

The fluorescent excitation emission matrix (FEEM) was utilized to evaluate the removal of organic matter by stabilization ponds, which consist of aeration, facultative, and oxidation ponds of a central wastewater treatment plant of an industrial estate in northern Thailand. The result shows that six fluorescent peaks of influent wastewater and effluent water after aeration, facultative, and oxidation ponds were detected from the FEEMs at 230 nmEx/295 nmEm (A), 275 nmEx/300 nmEm (B), 240 nmEx/355 nmEm (C), 280 nmEx/355 nmEm (D), 275 nmEx/410 nmEm (E) and 330 nmEx/410 nmEm (F). The putative origins of peaks A and B, C and D, and E and F were tyrosine-like, tryptophan-like, and humic and fulvic acid-like substances, respectively. The aeration pond was the main course of action used to reduce the tyrosine-like substances at peaks A and B by 88 and 52%, respectively, and tryptophan-like substances at peaks C and D by 43 and 39%, respectively. There was only a 20 per cent decrease of humic and fulvic acid-like substances at peak E and an 18 per cent decrease at peak F through the use of aeration ponds. Total per cent reductions of total fluorescent organic matter after aeration ponds; facultative ponds; and oxidation ponds were 46, 51 and 54%, respectively. These values were notably similar to the total percent reduction of DOC by the same respective processes at 54, 53, and 55%.
Treatment of oilfield produced water by waste stabilization ponds
Authors: Shpiner R. , Vathi S. , Stuckey D.C.
Published: May 2007

Produced water (PW) from oil wells can serve as an alternative water resource for agriculture if the main pollutants (hydrocarbons and heavy metals) can be removed to below irrigation standards. Waste stabilization ponds seem like a promising solution for PW treatment, especially in the Middle East where solar radiation is high and land is available. In this work, hydrocarbon removal from PW in a biological waste stabilization pond was examined at lab-scale followed by an intermittent slow sand filter. The system was run for 300 days and removed around 90% of the oil in the pond, and 95% after the sand filter. COD removal was about 80% in the pond effluent, and 85% after the filter. The system was tested under various operational modes and found to be stable to shock loads. Installation of oil booms and decantation of surface oil seem to be important in order to maintain good system performance over time.
Influence of annual climate variability on design and operation of waste stabilisation ponds for continental climates
Authors: Heaven S. , Salter A.M. , Clarke D.
Published: May 2007

WSPs are widely used in North America, and offer huge potential for other continental climate regions. The standard design and operating protocol is robust even at high latitudes, but may be conservative elsewhere. A simple model based on first-order kinetics for biochemical oxygen demand (BOD) is used to consider some alternative design and operating protocols, using long-term daily climate records for cities across continental central Asia. Options include changing the discharge period; retaining treated water in the pond over the winter; and changing the facultative pond loading. Annual variability in climate parameters has a major effect, in particular on the date at which treated wastewater meets appropriate standards for discharge or re-use: the earlier the discharge, the greater the variability in effluent quality. Skilful management of these systems may therefore be required to maximise their performance. While current models require development, it is clear modelling could provide tools and guidelines that would allow the design of continental climate WSP to be tailored to specific regional and local climate conditions.
Anaerobic pond treatment of wastewater containing sulphate
Authors: Rajbhandari B.K. , Annachhatre A.P.
Published: May 2007

Anaerobic ponds are usually used for treatment of industrial and agricultural wastes which contain high organic matter and sulphate. Competition for substrate between sulphate reducing bacteria and methane producing archaea, and the inhibitory effects of sulphide produced from microbial sulphate reduction reported in the literature varied considerably. In this research, a laboratory scale column-in-series anaerobic pond reactor, consisting of five cylindrical columns of acrylic tubes, was operated to evaluate the effect of COD and sulphate ratio on pond performance treating wastewater containing high organic matter and sulphate from a tapioca starch industry. The result depicted that no adverse effect of COD:SO4 ratios between 5 and 20 on overall COD removal performance of anaerobic pond operated with organic loading rate (OLR) of 150 to 600 g COD/m3d. Sulphate reducing bacteria could out-compete methane producing archaea for the same substrate at COD:SO4 ratio equal to or lower than 5 and OLR greater than 300 g COD/m3d. Sulphide inhibition was not observed on overall performance of pond up to an influent sulphate concentration of 650 mg/L.
Modeling of anaerobic treatment of wastewater in ponds
Authors: Rajbhandari B.K. , Annachhatre A.P. , Vasel J.L.
Published: May 2007

A mathematical model to simulate the performance of anaerobic ponds was developed incorporating both settling of particulate components and the biological anaerobic digestion process. The biological activity includes solubilization of particulate organic matter; methanogenesis and the sulphate reduction process. The model considers that an anaerobic pond comprises a series of equal size columns. Each column has three compartments viz. liquid layer, active sediment layer and inert sediment layer. The existence of organic matter and sulphate removal mechanisms both in the bulk as well as sediment layer of the ponds and the exchange of the soluble components between the layers has been included in the model. The model was transferred to a computer program using VisSim Basic software. The model was verified by comparing simulated results with full-scale as well as with laboratory-scale anaerobic pond performance data. A good agreement between the simulated and the observed pond performance was achieved.
Über Osonhydrazone. II. Mitteil.: Zur Konstitution des Fructoson‐methyl‐phenylhydrazons
Authors: Henseke Günter , Hantschel Heinrich
Published: May 2007

Für das d‐Fructoson‐methyl‐phenylhydrazon wurde die Konstitution eines 1‐[Methyl‐phenylhydrazons] des Fructosons bewiesen. Das von E. E. Und E. G. V. Percival als Pyrazolverbindung formulierte Anhydro‐Derivat des Mischosazons A. erwies sich als ein 3.6‐Anhydro‐1‐[methyl‐phenyl]‐2‐phenyl‐psicose‐osazon, während das Mischosazon A ein 1‐[Methyl‐phenyl]‐2‐phenyl‐fructosazon darstellt.
Umsetzungen von Komplexen aus Verbindungen mit polarisierter C‐C‐Doppelbindung und Lithiumaluminiumhydrid (Reduktionen mit LiAlH4, VII. Mitteil.)
Authors: Dornow Alfred , Bartsch Werner
Published: May 2007

Einige Umsetzungsprodukte aus Verbindungen mit polarisierter C‐C‐Doppelbindung und Lithiumaluminiumhydrid dienen zur Hervon 1.4‐Diolen.
Synthese eines Benzolanalogen eines Chlordan‐Bestandteils
Authors: Bernimolin Jacques
Published: May 2007

Die beiden Diastereoisomeren des 1.2.4.5.6.7‐Hexachlor‐hydrindens wurden dargestellt und die insecticide Wirksamkeit des einen untersucht. Es besitzt nur eine unbedeutende Aktivität.
Derivate der 2.4.6‐Trijod‐3‐amino‐benzoesäure
Authors: Priewe Hans , Rutkowski Rudi , Pirner Klaus , Junkmann Karl
Published: May 2007

Derivate, insbesondere Dicarbonsäure‐dianilid‐Derivate, der 2.4.6‐Trijod‐3‐amino‐benzoesäure werden beschrieben, von denen das Adipinsäure‐bis‐[2.4.6‐trijod‐3‐carboxy‐anilid] Anwendung als neuartiges Gallenweg‐Röntgenkontrastmittel gefunden hat.
Über das physikalischchemische Verhalten des Dinatriumsalzes des Adipinsäure‐bis‐[2.4.6‐trijod‐3‐carboxy‐anilids] und anderer Trijodbenzolderivate
Authors: Neudert Walter , Röpke Horst
Published: May 2007

An dem Gallenweg‐Röntgenkontrastmittel – dem Dinatriumsalz des Adipinsaure‐bis‐[2.4.6‐trijod‐3‐carboxy‐anilids]1) (I) – und der entsprechenden freien Säure ((I)‐Säure) werden einige physikochemische Untersuchungen über UV‐Spektrophotometrie, Kapillar‐ und Kolloideigenschaften, Löslichkeiten, elektrochemische und Dissoziationsverhältnisse, Refraktometrie, Dichte usw. beschrieben, z. Tl. im Vergleich mit dem Natriumsalz der 2.4.6‐Trijod‐3‐acetamino‐benzoesäure (II), der entspr. (II)‐Säure und anderen Trijodbenzolderivaten. Hierbei wurden folgende Ergebnisse erhalten:

Die Trijod‐Substitution im Benzolkern bewirkt im UV‐Spektrum eine starke Erhöhung des molaren Extinktionskoeffizienten und eine Vereinfachung des Spektrums.

Trijodbenzolderivate mit einer freien NH2‐Gruppe zeigen ein kleines, zusätzliches Maximum im langwelligen UV.

Durch Wasserabspaltung entstehen bei der I‐Säure Molekülaggregate vom 16 fachen Mol.‐Gew. (im Durchschnitt) und bedingen kolloide Eigenschaften.

Gemäß ihrer Struktur zeigt I kapillaraktive Eigenschaften (Mizellbildung) und hat somit Ähnlichkeit mit den Seifen (ausgeprägte dynamische Oberflächenspannungserniedrigung).
Die elektrolytische Oxydation von Alkinolen
Authors: Wolf Viktor
Published: May 2007

Die elektrolytische Oxydation von primären und sekundären Acetylenalkoholen führte in saurer Lösung zu Acetylencarbonsäuren und Acetylenketonen. Die Reaktion wurde in Abhängigkeit von elektrochemischen Faktoren untersucht.
Synthese der bi‐homologen Reihe der symm. Dialkyl‐glykolsäuren (IX. Mitteil. über isomere und homologe Reihen))
Authors: Breusch Friedrich L. , Baykut Fikret , Ulusoy Emin
Published: May 2007

Die symmetrischen Dialkyl‐glykolsäuren bis zur Di‐n‐octadecyl‐glykolsäure wurden durch Kondensation von Oxalsäure‐monoäthylester‐chlorid mit Alkyl‐zinkjodiden dargestellt.
Die Umsetzung von Gramin und verwandten Verbindungen mit aromatischen Aminen. Über die Hofmann‐Martius‐Umlagerung beim Methyl‐phenyl‐skatyl‐amin
Authors: Thesing Jan , Mayer Hans
Published: May 2007

Beim Erhitzen von Gramin oder Gramin‐methosulfat mit Methylanilin bzw. Dimethylanilin entstehen unter C‐Alkylierung die entsprechenden p‐Skatyl‐aniline. Im Gegensatz dazu führt die Einwirkung von Alkali auf eine wäßr. Lösung von Gramin‐methosulfat und Methylanilin‐acetat bei Zimmertemperatur unter N‐Alkylierung zum Methyl‐phenyl‐skatyl‐amin. Letzteres bildet sich auch aus Indol, Formaldehyd und Methylanilin in Alkohol. Daβ dagegen bei der gleichen Umsetzung in Eisessig N‐Methyl‐p‐skatyl‐anilin gebildet wird, beruht darauf, daβ intermediär Methyl‐phenyl‐skatyl‐amin entsteht, das sich in Eisessig im Sinne einer Hofmann‐Martius‐Umlagerung zu N‐Methyl‐p‐skatyl‐anilin umlagert. Es wird nachgewiesen, daβ diese „Umlagerung”︁ in Wirklichkeit eine intermolekular ablaufende Reaktion ist.

Die Einwirkung von Methyljodid auf Methyl‐phenyl‐skatyl‐amin in Aceton führt unter Umlagerung zu N.N‐Dimethyl‐p‐skatyl‐anilin sowie zu dessen Jodmethylat. N.N.‐Dimethyl‐p‐skatyl‐anilin entsteht auch unter Abspaltung von Methylanilin, Phenylhydroxylamin bzw. Wasser bei der Einwirkung von Methyl‐phenyl‐skatyl‐amin, N‐Phenyl‐N‐skatyl‐hydroxylamin bzw. von 3‐Oxymethyl‐indol auf Dimethylanilin bei Zimmertemperatur in Eisessig.
Über die Kondensation von Dimethyl‐alloxan mit o‐Phenylendiamin
Authors: Bredereck Hellmut , Pfleiderer Wolfgang
Published: May 2007

Die Kondensation von o‐Phenylendiamin‐hydrochlorid mit Dimethyl‐alloxan führt zum 1.3‐Dimethyl‐alloxazin. Bei der alkalischen Spaltung entsteht als Endprodukt die 3‐Methylamino‐chinoxalin‐carbonsäure‐(2).

Die entsprechende neutrale Kondensation liefert 3‐Oxy‐chinoxalin carbonsäure (2) N‐methyl‐amid, aus dem mit Alkali die 3‐Oxychinoxalin‐carbonsäure‐(2) hervorgeht.
Über die katalytische Oxydation von Methylchinolinen zu Chinolinaldehyden in der Gasphase
Authors: Mathes Wilhelm , Sauermilch Walter
Published: May 2007

Es wird ein technisch anwendbares Verfahren zur Darstellung von Chinolinaldehyden durch katalytische Oxydation der entsprechenden Methylchinoline beschrieben.
Über die Sulfonierungsprodukte des 2‐Acetylamino‐thiophens und die Darstellung der 2‐Amino‐thiophen‐sulfonsäure‐(5
Authors: Scheibler Helmuth , Keintzel Ernst , Falk Klaus
Published: May 2007

Die Versuchsbedingungen für die Bildung der einzelnen bei der Einwirkung von Schwefelsäure auf 2‐Acetylamino‐thiophen entstehenden Sulfonsäuren wurden ausgearbeitet und diese in Form der freien Säuren isoliert. Aus 2‐Amino‐thiophen‐disulfonsäure‐(3.5) wurde über die Diazoverbindung Thiophen‐disulfonsäure‐(3.5), aus 2‐Acetylamino‐sulfonsäure‐(5) die 2‐Amino‐thiophen‐sulfonsäure‐(5) dargestellt. Diese unterscheidet sich in ihren chemischen Eigenschaften deutlich von der Sulfanilsäure, dem entsprechenden Benzolderivat.
Über Sulfonamide der Thiophenreihe
Authors: Scheibler Helmuth , Falk Klaus
Published: May 2007

Aus der 2‐Acetylamino‐thiophen‐sulfonsäure‐(5) wurde das Sulfonsäurechlorid dargestellt, aus dem das Sulfonamid, das Sulfanilid, das Sulfonamidopyridin‐Derivat und der Sulfonsäure‐äthylester erhalten wurden.