39 research outputs found
Evaluating the Performance of Georgia\u2019s CRCPs Using Ground Penetrating Radar (GPR)
PI#0015304In an effort to provide reliable decisions regarding highway pavements, condition assessment is often conducted to evaluate pavement performance. For Continuously Reinforced Concrete Pavements (CRCP) evaluated in this study, pavement distress is classified as having transverse and longitudinal cracks and/or punchouts. This report evaluated the influence of reinforcement placement and concrete cover on distresses through the use of non-destructive testing methods that included Ground Penetrating Radar (GPR) and eddy current technology. In addition, this research evaluated whether an eddy current technology could be used in the absence of a cored sample for the calibration process of GPR in the field. Ultimately, information on pavement distress type and severity, reinforcement location, and cover depth was collected for six CRCP sites on major interstates in Georgia. This study confirmed that the location and depth of reinforcements affect the performance of CRCPs in terms of cluster cracking and punchouts
Development of a reverse transcription-polymerase chain reaction (RT-PCR) assay for the detection of Amasya cherry disease
A reverse transcription-polymerase chain reaction (RT-PCR) procedure was developed to detect Amasya cherry disease (ACD) in naturally infected sweet cherry (Prunus avium) leaves sampled from Turkey. The procedure was based on detection of the presence of a mycoviral-like double-stranded RNA (dsRNA) of 5.3 kbp always found in association with ACD, which is probably caused by a fungus. Specific primers were designed to amplify a fragment of the diagnostic dsRNA. The method will improve routine diagnosis of ACD in Prunus spp.Peer reviewe
Molecular, serological and transmission electron microscopic analysis of the barley yellow dwarf virus- PAV and the cereal yellow dwarf virus-RPV in canary seed ( Phalaris canariensis L.)
Canary seed (
Phalaris canariensis
L.) is a cereal crop belonging to the tribe
Phalarideae
of the
Poaceae
family. A prevailing virus infection, which causes dwarfing of plants and yellowing of leaves, was observed in canary seed fields in the Tekirdag province of Turkey. The aim of this study was to identify, clone and sequence the cereal viruses naturally occurring on
P. canariensis
by employing serological tests as DAS-ELISA and TAS-ELISA tests combined with transmission electron microcopy (TEM) and molecular analysis. One hundred and one plant samples showing symptoms were collected and tested serologically using polyclonal antisera against
Barley yellow dwarf virus
-PAV (BYDV-PAV) and
Cereal yellow dwarf virus
-RPV (CYDV-RPV). The results of both immunoassays showed that 48% of the samples were infected with BYDV-PAV, 2% with CYDV-RPV and 14% were mixed infection. 36% of the samples were uninfected or infected at level below detection. Aphid transmission experiments revealed that barley (cv. Rubina) exhibited characteristic of CYDV-RPV. Investigations of infected canary grass seedlings using transmission electron microscopy (TEM) supported the findings of serological tests and revealed the presence of isometric particles of approximately 25 nm in diameter. These results were also confirmed by using BYDV-PAV and CYDV-RPV specific primers. Sequence analysis of cDNA and probable translation products revealed a high level of homology to BYDV-PAV and CYDV-RPV isolates found in other plant species. The sequence data obtained from this research were deposited in the EMBL/GenBank Data Libraries under the accession nos. EGO19056 and EF372272
Bond energies of ThO(+) and ThC(+): A guided ion beam and quantum chemical investigation of the reactions of thorium cation with O2 and CO
Kinetic energy dependent reactions of Th(+) with O2 and CO are studied using a guided ion beam tandem mass spectrometer. The formation of ThO(+) in the reaction of Th(+) with O2 is observed to be exothermic and barrierless with a reaction efficiency at low energies of k/kLGS = 1.21 ± 0.24 similar to the efficiency observed in ion cyclotron resonance experiments. Formation of ThO(+) and ThC(+) in the reaction of Th(+) with CO is endothermic in both cases. The kinetic energy dependent cross sections for formation of these product ions were evaluated to determine 0 K bond dissociation energies (BDEs) of D0(Th(+)-O) = 8.57 ± 0.14 eV and D0(Th(+)-C) = 4.82 ± 0.29 eV. The present value of D0 (Th(+)-O) is within experimental uncertainty of previously reported experimental values, whereas this is the first report of D0 (Th(+)-C). Both BDEs are observed to be larger than those of their transition metal congeners, TiL(+), ZrL(+), and HfL(+) (L = O and C), believed to be a result of lanthanide contraction. Additionally, the reactions were explored by quantum chemical calculations, including a full Feller-Peterson-Dixon composite approach with correlation contributions up to coupled-cluster singles and doubles with iterative triples and quadruples (CCSDTQ) for ThC, ThC(+), ThO, and ThO(+), as well as more approximate CCSD with perturbative (triples) [CCSD(T)] calculations where a semi-empirical model was used to estimate spin-orbit energy contributions. Finally, the ThO(+) BDE is compared to other actinide (An) oxide cation BDEs and a simple model utilizing An(+) promotion energies to the reactive state is used to estimate AnO(+) and AnC(+) BDEs. For AnO(+), this model yields predictions that are typically within experimental uncertainty and performs better than density functional theory calculations presented previously