Gel Precipitation Research Articles

Using DET and DGT probes (ferrihydrite and titanium dioxide) to investigate arsenic concentrations in soil porewater of an arsenic-contaminated paddy field in Bangladesh

Arsenic concentration in the pore water of paddy fields (Csoln) irrigated with arsenic-rich groundwater is a key parameter in arsenic uptake by rice. Pore water extracts from cores and in situ deployment of DET and DGT probes were used to measure the arsenic concentration in the pore water. Ferrihydrite (Fe) and titanium dioxide (Ti) were used as DGT binding agents. Six sampling events during different growing stages of the rice, inducing different biogeochemical conditions, were performed in one rice field. A time series of DGT experiments allow the determination of an in situ arsenic diffusion coefficient in the diffusive gel (3.34×10−6cm2s−1) needed to calculate the so-called CDGT(Fe) and CDGT(Ti) concentrations. Over 3days of a given sampling event and for cores sampled at intervals smaller than 50cm, great variability in arsenic Csoln concentrations between vertical profiles was observed, with maxima of concentrations varying from 690 to 2800μgL−1. Comparisons between arsenic measured Csol and CDET and calculated CDGT(Fe) and CDGT(Ti) concentrations show either, in a few cases, roughly similar vertical profiles, or in other cases, significantly different profiles. An established iron oxyhydroxide precipitation in the DET gel may explain why measured arsenic CDET concentrations occasionally exceeded Csoln. The large spread in results suggests limitations to the use of DET and type of DGT probes used here for similarly representing the spatio-temporal variations of arsenic content in soil pore water in specific environmental such as paddy soils.

Synthesis and characterisation of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) Zr(IV) monothiophosphate composite cation exchanger: analytical application in the selective separation of lead metal ions

In this study, poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) zirconium(IV) monothiophosphate composite cation exchanger was prepared by sol–gel precipitation method. The presence of sulphur in the cation exchanger enhances affinity towards the heavy metal ions which can improve the selectivity of the material. The selectivity studies showed that the material is selective towards Pb(II) ions. To characterise the material, several physicochemical properties were also studied which includes X-ray, scanning electron microscopy and transmission electron microscopy studies. The ion-exchange behaviour of this cation exchanger was studied by using some of the selected properties like ion-exhange capacity for various metal ions, elution, effect of eluent concentration, thermal effect on ion-exchange capacity (IEC). The results of IEC and physicochemical properties revealed that the material is nanocomposite, crystalline, chemically, mechanically and thermally stable. The analytical ability of this cation exchanger was demonstrated in binary separation of Pb(II) ions from a mixture of other metal ions. The recovery is qualitative and the separations are reproducible.

Characteristics and properties of hydoxyapatite derived by sol–gel and wet chemical precipitation methods

The synthesis of crystalline hydroxyapatite (HA) nanoparticles with expected microstructure is of primary importance because the process directly relates to the phase purity, morphology, and particle size of the final HA particles. In this work, different morphologies of HA powders were prepared via wet precipitation (HA–Wp) and sol–gel synthesis (HA–Sg) methods. The results showed that pure HA powders were successfully obtained via the two different methods, in which HA–Wp presented smaller crystallite size in accordance with the larger specific area compared with HA–Sg powders. A high surface area of 97.4m2g−1 was obtained in HA-Wp powder, whereas that of HA–Sg powder was 9.0m2g−1. Upon calcinations at 800–1000°C, the calcined powders were found to be Ca-deficient apatites as HA-Wp and HA–Sg powders decomposed to the secondary phase of β-TCP at 900°C and 1000°C, respectively. Microstructural analysis showed significant difference in terms of HA morphologies produced via the two methods. The HA-Wp powder consisted of nanoscale needle-like structures with soft agglomerated particles, whereas HA–Sg powder exhibited nanoglobular-like structures with hard agglomerated particles. The characteristics of nanocrystalline HA powder obtained from wet chemical precipitation is known to exhibit high surface activity as a bone substitute material.

Rational design of a cytotoxic dinuclear Cu2 complex that binds by molecular recognition at two neighboring phosphates of the DNA backbone.

The mechanism of the cytotoxic function of cisplatin and related anticancer drugs is based on their binding to the nucleobases of DNA. The development of new classes of anticancer drugs requires establishing other binding modes. Therefore, we performed a rational design for complexes that target two neighboring phosphates of the DNA backbone by molecular recognition resulting in a family of dinuclear complexes based on 2,7-disubstituted 1,8-naphthalenediol. This rigid backbone preorganizes the two metal ions for molecular recognition at the distance of two neighboring phosphates in DNA of 6-7 Å. Additionally, bulky chelating pendant arms in the 2,7-position impede nucleobase complexation by steric hindrance. We successfully synthesized the Cu(II)2 complex of the designed family of dinuclear complexes and studied its binding to dsDNA by independent ensemble and single-molecule methods like gel electrophoresis, precipitation, and titration experiments followed by UV-vis spectroscopy, atomic force microscopy (AFM), as well as optical tweezers (OT) and magnetic tweezers (MT) DNA stretching. The observed irreversible binding of our dinuclear Cu(II)2 complex to dsDNA leads to a blocking of DNA synthesis as studied by polymerase chain reactions and cytotoxicity for human cancer cells.

Surveillance and characterization of Riemerella anatipestifer from wild birds in South Korea.

We conducted surveillance for Riemerella anatipestifer (RA) in wild birds along the East Asian-Australasian flyway in South Korea. Detected RA were characterized by serotype, antibiotic susceptibility, and sequence analysis of the 16S rRNA gene. We collected 944 wild birds of 34 species from 19 of South Korea's major migratory wild bird habitats between 2011 and 2012. We identified RA by PCR and rRNA gene sequence in 71/102 (69.6%) pharyngeal swabs and 19/944 (2.0%) cloacal swabs of wild birds. Most RA positives (71/75 [95%] pharyngeal and 19/704 [(2.6%] cloacal) were from three duck species (family Anatidae): Mallard Duck (Anas platyrhynchos), Northern Pintail (Anas acuta), and Spot-billed Duck (Anas poecilorhyncha). Thirty-three RA isolates obtained and examined were highly resistant to aminoglycosides: kanamycin (100%), gentamicin (94%), amikacin (91%), neomycin (88%), and streptomycin (82%). Six isolates were identified as serotype 4 by agar gel precipitation. Serotypes 1 and 7, which are known virulent serotypes, were also identified in three isolates from wild duck species.

Recovery of Cobalt Ion into Polyethyleneglycol (PEG) Gel Phase as Thiocyanato Complex

This study outlines the recovery of cobalt (Co) ion as a gel phase consists of PEG and Co-thiocyanato complex (Co(NCS)4) from aqueous solution. Taking advantage of gel precipitation with composition written as (PEG)nCo(NCS)4K2, a novel process for the efficient recovery of Co was proposed. Composition of gel phase and load capacity of Co ion in it was investigated by fundamental experiment. Gel precipitation from aqueous solution of nickel sulfate (NiSO4), cobalt sulfate (CoSO4) and potassium thiocyanate (KSCN) was observed by mixing it with polyethyleneglycol (PEG#4000, molar weight; 2,70033,500) aqueous solution. The results confirmed the large load capacity of Co (6.8 © 1014mol/1 g of gel phase) compared to the sorption to polyurethane foam reported in the past. Percentage of Co ion to the total amount of Ni and Co ions in gel phase were more than 99.6 at%, revealing excellent condensation efficiency for Co. Furthermore, Co ion was extracted and separated from SCN and PEG in gel phase, by utilizing solvent extraction. From the set of experimental results, feasibility of the proposed process was discussed. [doi:10.2320/matertrans.M2014428]

Seroprevalence studies on animal chlamydiosis amongst ruminants in five states of India.

Background and Aim:Animal chlamydiosis, caused by different chlamydial species, is characterized by clinical or subclinical disease manifestations in cattle, buffalo, ovine, caprine and wild animal species. Animal chlamydiosis often remains underdiagnosed or undiagnosed, and its status in many parts of India is still unknown. Hence, the present study was conducted to determine the seroprevalence of animal chlamydiosis amongst ruminant livestock species of five states of India.Materials and Methods:Totally, 2127 randomly selected serum samples collected from ruminant livestock species viz. cattle (n=430), buffaloes (n=429), sheep (906) and goats (n=362), were tested by agar gel precipitation test for chlamydiosis between 2002 and 2011. Precipitating antigen was prepared from locally isolated strain of Chlamydia psittaci after treatment with sodium deoxycholate.Results:The chlamydial seroprevalence detected amongst ruminants in five states of India was: Himachal Pradesh: Cattle-10.90%, sheep-10.60% and goats- 22.46%; Punjab: Cattle-1.45%; Andhra Pradesh: Cattle-2.80%, buffaloes-0.93%, sheep-8.90% and goats-9.46%; Maharashtra: goats-8.33%; Jammu and Kashmir: sheep-12.50%. The mean seroprevalence values of each animal species are: Cattle-4.65%, buffaloes-0.93%, sheep-9.82% and goats-19.33%.Conclusion:The results indicate the endemic nature of animal chlamydiosis across five states in India. Hence, it requires further extensive studies in other parts of India also using chlamydial species-specific diagnostics to ascertain overall countrywide prevalence of the disease. The zoonotic nature of the chlamydiae of ruminant origin further adds significance to such prevalence studies.

An abiotic model for the development of textures in some South Atlantic early Cretaceous lacustrine carbonates

Abstract The cyclic distribution of various types of carbonates and Mg-clays in early Cretaceous rift-sag phase lacustrine carbonates from the subsurface of the South Atlantic provides an insight into how evolving lake chemistries in highly alkaline settings control facies development. The typically subdecametre scale symmetrical and asymmetrical cyclothems exhibit three main components: mud-grade laminated carbonates, millimetre-diameter spherulites with evidence of having been in a matrix of Mg-silicates, and millimetre–centimetre calcitic shrub-like growths. The laminites contain conspicuous numbers of ostracods and vertebrate remains and were produced by short-lived pluvial events, causing expansion of shallow lakes. Later evaporation triggered Mg-silicate precipitation and calcite nucleation within gels to produce spherulitic textures. When the rate of gel precipitation decreased or ceased, calcite growth, now less inhibited, produced shrub-like calcites resembling those produced abiotically in modern travertines, although still with some evidence of the former presence of some Mg-silicates. Physical reworking of these sediments led to the dispersion of the gels and the concentration of detrital carbonate components. Despite earlier proposals, evidence of microbial processes producing carbonates in these Cretaceous lake deposits is rare and the application of facies models based on modern and ancient microbialite analogues maybe be misplaced.

Production and characterization protein of anti HIV specific immunoglobulin Y for Immunotherapy

In this study, an approach for large-scale production of immunoglobulin Y ( Ig Y) specific anti Human Immunodeficiency Virus (HIV) for use as a potential immunotherapy for HIV disease. Lohman laying hens were immunized intramuscularly with HIV virus that had been inactivated using formaline. The immunizations were repeated two times with dose of each 1 ml of HIV antigen (20 copy/ml) with an interval of two week. The first immunizations were HIV antigen mixed with Fruend Adjuvant Complete and subsequently mixed with Freund Adjuvant Incomplete. Egg yolk was separated from egg white and immunoglobulin Y (IgY) antibody was then purified by multiple polyethylene glycol (PEG) 6000 extraction and ammonium sulfate purification steps. Antibody response in yolk was detected by agar gel precipitation test (AGPT) and the protein pattern was detected using polyacrilamid gel electrophoresis (SDS-PAGE). Specific activity of the antibody was tested using commercial ELISA. Antibody of HIV was detected and produce a specific line of precipitation in AGPT beginning the second week after the first immunization. Analysis of results obtained with ELISA showed significant increase in the HIV-specific antibodies after two weeks from the primary immunization. Through the effect of boostering; the anti-HIV antibody levels reached a plateau at six weeks from the primary immunization and remained significantly higher till the end of observation period. SDS-PAGE revealed the IgY preparation to be pure and dissociated into protein bands with molecular weights of 164; 87; 68, and 37 kDa. These results suggested that chicken IgY could be a practical strategy in large-scale production of Ig Y specific anti HIV for immunotherapy and diagnostic KIT of HIV disease.

A novel preparation approach and denitrification performance of TiO2/Fe0 photocatalysts

Chemical vapor hydrolysis deposition (CVHD), a novel method for preparation of TiO2/Fe0 is presented. In the method, tetrabutyl titanate (TBT) and sponge iron (Fes) are used as precursor and carrier, respectively. Especially, TBT was hydrolyzed slowly with the thin water vapor to create TiO2 nanoparticles on the Fes carrier. The experiment showed that the optimal preparation conditions for TiO2/Fe0 via CVHD were calcination temperature of 723 K and TiO2-loading amount of 7.57%. The as-prepared TiO2/Fe0 catalysts were evaluated by the catalytic reaction of nitrate reduction, and exhibited a higher catalytic activity and selectivity than the similar catalysts prepared with the typical methods of sol–gel or alkoxide hydrolysis precipitation. The present results demonstrate that the selective nitrate reduction over TiO2/Fe0 catalysts with HCOOH as the hole scavenger, highlighting the validity of removal of aqueous nitrate by photocatalysis.

Occurrence of Newcastle Disease and Infectious Bursal Disease Virus Antibodies in Double-Spurred Francolins in Nigeria.

The double-spurred francolin Francolinus bicalcaratus has been identified as a good candidate for future domestication due to the universal acceptability of its meat and its adaptability to anthropogenically altered environments. Therefore, in investigating the diseases to which they are susceptible, serum samples from 56 francolins in a major live-bird market (LBM) in Ibadan, southwestern Nigeria, were screened for antibodies against Newcastle disease (ND) and infectious bursal disease (IBD) viruses. Haemagglutination inhibition (HI) test and enzyme-linked immunosorbent assay (ELISA) revealed 25.0% and 35.7% prevalence of ND virus (NDV) antibodies, respectively, while 5.4% and 57.1% prevalence of IBD virus (IBDV) antibodies was detected by agar gel precipitation test (AGPT) and ELISA, respectively. This first report on the occurrence of NDV and IBDV antibodies in apparently healthy, unvaccinated double-spurred francolins from a LBM suggests that they were subclinically infected with either field or vaccine viruses and could thus serve as possible reservoirs of these viruses to domestic poultry. Furthermore, if they are to be domesticated for intensive rearing, a vaccination plan including ND and IBD should be developed and implemented.

Apatite bone cement reinforced with calcium silicate fibers.

Several research efforts have been made in the attempt to reinforce calcium phosphate cements (CPCs) with polymeric and carbon fibers. Due to their low compatibility with the cement matrix, results were not satisfactory. In this context, calcium silicate fibers (CaSiO3) may be an alternative material to overcome the main drawback of reinforced CPCs since, despite of their good mechanical properties, they may interact chemically with the CPC matrix. In this work CaSiO3 fibers, with aspect ratio of 9.6, were synthesized by a reactive molten salt synthesis and used as reinforcement in apatite cement. 5 wt.% of reinforcement addition has increased the compressive strength of the CPC by 250% (from 14.5 to 50.4 MPa) without preventing the cement to set. Ca and Si release in samples containing fibers could be explained by CaSiO3 partial hydrolysis which leads to a quick increase in Ca concentration and in silica gel precipitation. The latter may be responsible for apatite precipitation in needle like form during cement setting reaction. The material developed presents potential properties to be employed in bone repair treatment.

Synthesis and Properties of Biphasic Calcium Phosphate Prepared by Different Methods

Hydroxapatite (HA) is a stable phase with low dissolution rate in body fluid. Meanwhile, β-tricalcium phosphate (β-TCP) is rather soluble but the dissolution rate is too fast for bone bonding. Therefore a mixture of both is desirable to control the bioresorbability. In this work, calcium phosphate powder has been synthesized via sol gel and wet precipitation method to compare phase behaviour of these powders upon calcination. XRD result clearly revealed that both as-synthesized powders were pure HA with good purity. The decomposition of HA to TCP took place in the range of 700-800 °C and 800-900 °C for sol gel and wet chemical precipitation powder, respectively. The weight loss detected at 700-850°C in TGA analysis confirmed the presence of this biphasic mixtures.From FTIR analysis, profound change in OH-band intensity was attributed to the increased in HA crystallinity with calcination temperature.

A Novel Synthesis Process of PPTA by Nitrogen Cooling for Reaction Heat Removal

Poly (p-phenylene terephthalamide) (PPTA) was synthesized by different processes including single feeding, batch feeding and inlet nitrogen cooling. The effects of these three processes on reaction heat removal of PPTA polymerization were compared. The degree of reaction heat removal was characterized through the changes of system temperature and stirring rate with reaction time. Results suggested that during the processes of batch feeding and nitrogen cooling, system temperature could be effectively decreased and PPTA yields were both larger than 98 %. It indicated that the exothemic heat could be transferred faster and better and monomers could completely react. The inlet incorporation of nitrogen cooling led to the maximum of inherent viscosity (ηinh) of resulted PPTA. This result indicated that nitrogen cooling could effectively transfer the reaction heat and prolong the gel precipitation time of PPTA.

Occurrence of reovirus infection in Muscovy ducks (Cairina moschata) in south western Poland.

During the summer 2012 an incidence of high mortality, above 44 percent, in two flocks of Muscovy ducklings in Poland was noted. The clinical signs included considerable weight loss and inability to walk. During the post-mortem evaluations dehydration and enteritis, gouty kidneys as well as hemorrhagic liver and spleen lesions were found. The laboratory diagnosis included agar gel precipitation assay (AGP) as well as polymerase chain reaction (PCR) or reverse transcription PCR for the presence of goose parvovirus (GPV), duck circovirus (DuCV), duck reovirus (DRV) and avian reovirus (ARV). Interestingly, the examinations performed by AGP showed partial reactivity of liver homogenates from Muscovy ducklings with chicken S1133 antiserum. The presence of duck reovirus RNA was also detected by real-time RT-PCR targeting the chicken reovirus sigma NS fragment, while the sequencing showed major similarity to chicken S1133, 1733, GX/2010/1 and TARV-MN2 reovirus strains. The virus sequence was also related to a previously isolated TH11 strain from Muscovy ducks in China. Further study is needed in order to explain the particular epidemiology of the reovirus infection of Muscovy ducklings.

Prevalence of multiple subtypes of influenza A virus in Japanese wild raccoons

Raccoons (Procyon lotor), which are not native to Japan, have been suspected to transmit various pathogens by frequent intrusion into agricultural and residential areas. To determine influenza A virus seropositivity in raccoons in Japan, we examined a total of 634 raccoons captured in 19 towns (A–S) from 2009 to 2012. Agar gel precipitation tests showed that the antibody prevalence was 1.89% (12/634). All positive raccoons were captured in three towns (A–C) located within a radius of approximately 30km, and 75% had antibodies to multiple subtypes (H1, H3–5, N1, N6, and N8). H3 and N8 antibodies were most frequently detected (75%). Among all the raccoons captured, 67% (8/12) were found in town A in 2009 and 2010, and all five raccoons captured in 2010 had H3 and N8 antibodies, suggesting that transmission of the subtype might occur. H5 and N1 antibodies were also detected in two raccoons captured in town A. Virus neutralization tests examining the highly pathogenic avian influenza virus (HPAIV) H5N1 subtype (four isolates of which have been detected in Japan to date) and the low PAIV (LPAIV) H5N3 subtype showed that raccoon sera highly cross-reacted with three H5N1 strains (clade 2.5: Ck/Yamaguchi/7/04; clade 2.3.2.1: Whooper swan/Hokkaido/1/08 and Whooper swan/Hamanaka/11), while they displayed a low cross-reactivity with the antisera to the clade 2.2 virus (Ck/Miyazaki/K11/07) and H5N3 LPAIV (Whistling swan/Shimane/499/83). Thus, the origin of the H5N1 virus was not clearly defined. The viral M gene was detected in four antibody-negative raccoons captured in three towns by real-time reverse transcription-polymerase chain reaction (rRT-PCR) with high Ct values, although no virus was isolated. This study is the first report showing that raccoons of Japan were infected with multiple subtypes of influenza A virus, including H5N1. It remains to be elucidated how raccoons play a role in persistence of influenza A virus in nature and if they could pose risks to animal and human health, for example, by playing a role as “mixing vessel” to generate novel strains of influenza A virus.

Preparation and characterization of negatively charged organic–inorganic hybrid ultrafiltration membranes for protein separation

Negatively charged organic–inorganic hybrid ultrafiltration membranes with adjustable charge density were fabricated from blends of water soluble poly vinyl alcohol and N-O-sulfonic acid benzyl chitosan (NSBC) in combination with tetraethyl orthosilicate (TEOS) silica precursor by the sol–gel method and precipitation in a mixture of methanol and water (80wt%:20wt%) solvent. The porous hybrid membrane morphologies, structures and surface properties were characterized comprehensively using scanning electron microscopy, Fourier transform infrared spectroscopy in the attenuated total reflection mode, as well as contact angle measurements. The results confirmed that the fabricated membranes were porous, hydrophilic and mildly charged in nature. The water flux and flux recovery ratio (i.e. protein fouling resistance) of the membranes were highly dependent on the fraction of NSBC. The protein transmission as a function of pH and the fraction of NSBC was studied for two model proteins (bovine serum albumin; BSA and lysozyme; LYZ) and found to be controlled by size exclusion and the fraction of NSBC, and therefore the membrane charge density. The highest transmission of proteins at their isoelectric points was obtained for the membrane containing 40wt% of NSBC. The best separation of LYZ from BSA in the model mixture solution was obtained at pH=11 when membrane C-40 was used in ultrafiltration of protein solution.

Prognostic impact of diastolic blood pressure on long-term outcome in patients with non-ST-segment elevation myocardial infarction

Raccoons (Procyon lotor), which are not native to Japan, have been suspected to transmit various pathogens by frequent intrusion into agricultural and residential areas. To determine influenza A virus seropositivity in raccoons in Japan, we examined a total of 634 raccoons captured in 19 towns (A–S) from 2009 to 2012. Agar gel precipitation tests showed that the antibody prevalence was 1.89% (12/634). All positive raccoons were captured in three towns (A–C) located within a radius of approximately 30 km, and 75% had antibodies to multiple subtypes (H1, H3–5, N1, N6, and N8). H3 and N8 antibodies were most frequently detected (75%). Among all the raccoons captured, 67% (8/12) were found in town A in 2009 and 2010, and all five raccoons captured in 2010 had H3 and N8 antibodies, suggesting that transmission of the subtype might occur. H5 and N1 antibodies were also detected in two raccoons captured in town A. Virus neutralization tests examining the highly pathogenic avian influenza virus (HPAIV) H5N1 subtype (four isolates of which have been detected in Japan to date) and the low PAIV (LPAIV) H5N3 subtype showed that raccoon sera highly cross-reacted with three H5N1 strains (clade 2.5: Ck/Yamaguchi/7/04; clade 2.3.2.1: Whooper swan/Hokkaido/1/08 and Whooper swan/Hamanaka/11), while they displayed a low cross-reactivity with the antisera to the clade 2.2 virus (Ck/Miyazaki/K11/07) and H5N3 LPAIV (Whistling swan/Shimane/499/83). Thus, the origin of the H5N1 virus was not clearly defined. The viral M gene was detected in four antibody-negative raccoons captured in three towns by real-time reverse transcription-polymerase chain reaction (rRT-PCR) with high Ct values, although no virus was isolated. This study is the first report showing that raccoons of Japan were infected with multiple subtypes of influenza A virus, including H5N1. It remains to be elucidated how raccoons play a role in persistence of influenza A virus in nature and if they could pose risks to animal and human health, for example, by playing a role as “mixing vessel” to generate novel strains of influenza A virus.

Investigation of Outbreaks of Infectious Bursa Disease in Zaria, Nigeria

Aim: To investigate outbreak of IBD in Zaria, Nigeria. Study Design: Prospective study. Place and Duration of Study: Sample: Poultry Unit of the Ahmadu Bello University Veterinary Teaching Hospital, Faculty of Veterinary Medicine, Ahmadu Bello University, Zaria between March 2009 to July 2009. Methodology: Poultry cases reported to the clinics were investigated. Date, age, address, flock size, morbidity rate, mortality rate, breed, species, type of birds, vaccination history were noted; post mortem and agar gel precipitation test were done on 10 flocks, the incidence rate, morbidity rate, mortality rate and organ (bursa, spleen and thymus) to body weight ratio of the 10 flocks were calculated. Results: Chicks in all the flocks revealed the clinicopathologic manisfestation of IBD which include depressions, somnolence, anorexia, ruffled feathers, trembling, postration followed by death. In all the flocks, the BF were either turgid, swollen and or Original Research Article International Journal of TROPICAL DISEASE & Health, 4(4): 411-426, 2014 412 haemorrhagic, severe haemorrhages on the thigh and pectoral muscles, haemorrhages at the junction of proventriculus and gizzard or oesophagus, congested or pale carcasses, swollen kidneys with prominent tubules and enlarged pale or congested liver were also observed during postmortem examination. All the bursal homogenates from the 10 flocks gave precipitation line in the AGPT. An incidence of 12.1% was recorded. Average morbidity (40.5%) and mortality (40.7%) rates were recorded in ten outbreaks of IBD. Improved breeds of chickens were more likely to suffer from IBD with broilers 3.87 times at risk. Birds, 3-6 weeks-old were at a risk of being infected with IBDV. Chickens vaccinated once against IBD were 4.8 times more likely to suffer from IBD. Conclusion: IBD is a disease of improved breeds of poultry with clinical disease seen only in chickens. The disease mostly affects chickens of 3 to 6 weeks of age. Birds vaccinated twice are less susceptible to the disease.

Zeolite Synthesis under Insertion of Silica Rich Filtration Residues from Industrial Wastewater Reconditioning

Zeolite synthesis was studied using two silica rich filtration residues (FR 1 and FR 2) as Si-source and sodium aluminate in a direct synthesis at 60°C at strong alkaline conditions (8 M - 16 M NaOH). In addition to these one-pot syntheses, a two-step process was investigated. Here, an alkaline digestion of FR at 60°C was followed by gel precipitation with sodium aluminate and gel crystallization under usual conditions of 80°C - 90°C. The results show that the substitution of chemical reagent sodium silicate by a waste material like FR as Si-source is possible but requires fine tuning of the reaction conditions as zeolite crystallization is a process under kinetic control. The solubility behaviour and impurities of the inserted filtration residues strongly influenced the course of reaction. Thus zeolites like hydrosodalite or intermediate zeolite between cancrinite and sodalite, or zeolite NaA or Z-21 in cocrystallization with hydrosodalite could be observed in the one pot syntheses already in a short time interval between 1 - 4 h depending on the alkalinity. The two step process yield to zeolites NaA and NaX in very good quality. The reaction process of FR in both reaction methods was characterized by chemical analyses, X-ray powder diffraction, Fourier transform infrared spectroscopy as well as scanning electron microscopy. Surface area and water content of selected products were further characterized by the BET-method and by thermogravimetry. Summing up the results, we can show that zeolite formation from filtration residues is possible by several reaction procedures as model cases for a re-use of industrial waste materials. Beside the importance for environmental protection, the reactions are of interest for zeolite chemistry as the re-use of FR is possible under economically conditions of low energy consumption at 60°C and short reaction periods.