Characterization of bending fatigue mini-specimens for nuclear materials

New materials with superior radiation and corrosion resistance are needed to improve the economy and performance of current nuclear reactors as well as future nuclear reactors. Measurement of mechanical properties of the material of equipment is required to estimate its safe operating life. Studying fatigue of irradiated specimens is challenging due to space limitation in research reactors (e.g. ATR). The mini-specimen bending fatigue (Krouse-type) of nuclear materials was used to study fatigue properties and compare the obtained results with that of reference data of full size specimen. These Krouse-type were made of austenitic SS304, SS316, HT9 ferritic martensitic steel, and Incoloy alloy MA956 oxide dispersion strengthens (ODS). A comparison between the mini-specimens and the standard specimen ASTM B593 had similar design but a smaller size. The bending fatigue machine VSS-40H was designed and LEF-150 was modified with a specially designed adapter to test the fatigue of the mini-specimen. Consequently, the S-N curve for both HT9 and Incoloy alloy MA956 were defined. The endurance limits were measured to be 94 MPa for HT9 and 132 MPa for Incoloy alloy MA956. The finite element model code ABAQUS was used to estimate the level of stress in the bent mini specimen. The plots indicated that the 3- parameter Weibull distribution fits the data well. The correlation coefficient value for 3-parameter Weibull was improved and increased by 33.66 % for the HT9, 30.88% for the as-received and 26.51% for the thermal aging for Incoloy alloy MA956. The thermal aging process had little impact on the mini-specimens fatigue life. The analysis of error propagation of specimen\u27s stress has been observed that the most of the error was in deflection measurements. Thus this Krouse-type was seen as the solution to studying fatigue of irradiated specimens as it can solve the challenge of limitation of space in research reactors. --Abstract, page iv

Aggressive Driving is a Major Cause of Traffic Accidents and Road Rage in Jordan

Motor vehicle accidents are a major cause of death among Jordanians. Roughly 700 people died last year in car accidents out of a total population of five million people. Many factors contribute to this. Some involve planning, design, construction, operation, surface condition, and policing of the roadways. The most deadly factor is human error. This includes unawareness of traffic rules and roadway condition; lack of driving skills; poor judgment; failure to interact and adjust to prevailing roadway conditions; and most importantly, aggressive driving. Preliminary findings of a survey questionnaire conducted in this study show that improper engineering design, inadequate traffic control, lack of traffic management, and traffic congestion are the main factors leading to aggressive driving and road rage on Jordan roadways. The study includes 200 questionnaires. The main objective of this study is to identify aggressive driving behaviors in Jordan and underline their effect on traffic safety. In addition, the study attempts to increase drivers’ awareness of their actions on the roadway and point out the consequences associated with these actions. Many drivers justify their aggressive driving as temporary retaliatory measures to counteract other aggressive drivers, and therefore, this leads to road rage and traffic chaos. Aggressive driving behaviors such as pushing a car off the roadway, deliberate obstruction of passing vehicles, pursuing a vehicle, excessive high speed, and tailgating are considered at the top of the list according to the study findings. Most drivers admit that driving 20km/hr above speed limit causes danger to pedestrians but not to other vehicles

Aggressive Driving is a Major Cause of Traffic Accidents and Road Rage in Jordan

Motor vehicle accidents are a major cause of death among Jordanians. Roughly 700 people died last year in car accidents out of a total population of five million people. Many factors contribute to this. Some involve planning, design, construction, operation, surface condition, and policing of the roadways. The most deadly factor is human error. This includes unawareness of traffic rules and roadway condition; lack of driving skills; poor judgment; failure to interact and adjust to prevailing roadway conditions; and most importantly, aggressive driving. Preliminary findings of a survey questionnaire conducted in this study show that improper engineering design, inadequate traffic control, lack of traffic management, and traffic congestion are the main factors leading to aggressive driving and road rage on Jordan roadways. The study includes 200 questionnaires. The main objective of this study is to identify aggressive driving behaviors in Jordan and underline their effect on traffic safety. In addition, the study attempts to increase drivers’ awareness of their actions on the roadway and point out the consequences associated with these actions. Many drivers justify their aggressive driving as temporary retaliatory measures to counteract other aggressive drivers, and therefore, this leads to road rage and traffic chaos. Aggressive driving behaviors such as pushing a car off the roadway, deliberate obstruction of passing vehicles, pursuing a vehicle, excessive high speed, and tailgating are considered at the top of the list according to the study findings. Most drivers admit that driving 20km/hr above speed limit causes danger to pedestrians but not to other vehicles

Photo-inhibition Effect from Strong Electron Withdrawing Nitro Group in N-[(E)(4-Bromophenyl)Methylidene]-4 Nitroaniline

Light induced effect of N-[(E)-(4-bromophenyl)methylidene]-4nitroaniline was investigated using UV-Vis spectrophotometer. This study revealed that the presence of strong electron withdrawing nitro group inhibited the photo-reactivity of the compound. Mainly, molecular structure and functional groups have tremendous influence on chromophoric compounds. The photoisomerization effect was not found in this compound, due to the photo-inhibition of nitro group present in the molecular system

The Relation Between Speed-Lane Choice and Road Accidents in Jordan

More than 96% of traffic casualties in Jordan take place on nonintersection roadway segments. Speed variation and improper lane change are considered to be some of the main factors contributing to these casualties. This research paper describes an attempt made to study speed-lane choice behavior in Jordan. Drivers’ behaviors with regard to their choice of speed and/or traveled lane are assessed. One-fifth of the observed drivers are speeding and one-forth of them changes lanes along the tested segment. Two models are developed and investigated to describe the relationships between speed and lane choice using binary and linear regression models. Results indicate that driving behavior varies with respect to roadway geometry and lane. Speed influences the driver choice of lane changing and his/her decision about changing lanes influences his/her speed choice

Ni incorporation in MgFe2O4 for improved CO splitting activity during solar fuel production

Efficacy of the sol–gel derived Ni-doped Mg-ferrites for an enhanced CO2 splitting activity is investigated. The results allied with the characterization indicate the formation of nominally phase pure Ni-doped Mg-ferrites with a coarser particle morphology. Ni-doped Mg-ferrites are further tested for multiple thermal reduction as well as CO2 splitting steps by using a thermogravimetric analyzer. The results associated with the thermogravimetric analysis confirmed that most of the Ni-doped Mg-ferrites attained a steady TR aptitude after crossing the 5th or 6th cycle. Likewise, the CS capability of all the Ni-doped Mg-ferrites accomplished consistency after 4th cycle (except for Ni0.11Mg0.88Fe2.01O4.005). The Ni0.90Mg0.11Fe2.04O4.070 showed the highest amount of O2 release (117.1 μmol/g cycle) and CO production (210.3 μmol/g cycle) in ten consecutive thermochemical cycles. Besides, Ni0.29Mg0.72Fe1.98O3.980 indicated better re-oxidation aptitude (nCO/nO2 ratio = 1.89) when compared with other Ni-doped Mg-ferrites

ROOTING OF DATE PALM (PHOENIX DACTYLIFERA L.) OFFSHOOTS BY ISOPROTHIOLANE (IPT)

The experiment was conducted at Alhassa Oasis (25° 22′ N' latitude; 49°34′ E longitude) and altitude is 179 m a.s.l , Kingdom of Saudi Arabia. Treatments included the following Isoprothiolane (IPT) concentrations incorporated at the bottom of offshoot hole: control (without IPT), 25g, 50g, 75g, 100g, 200g and 500g / offshoot hole. The offshoots weight ranged between 25 – 30 kg. The IPT concentrations of 75 and 100 g/ offshoot hole seemed to be quite optimal for improving rooting of date palm offshoots. The best rooting percentage, length of root, root fresh and dry weights were obtained under 75 and 100 g/ offshoot whole IPT concentrations. Offshoots under the control and the lowest and highest IPT treatments reflected poor rooting ability. The chlorophyll content data although looked relatively similar between treatments, a slight edge of 75 and 100 g/ offshoot hole was noticeable. This relative edge might have played a significant role in the photosynthetic ability of offshoots. The efficiency of rooting of offshoots under both concentrations might have resulted from their edged photosynthetic ability

ROOTING OF DATE PALM (PHOENIX DACTYLIFERA L.) OFFSHOOTS BY ISOPROTHIOLANE (IPT)

The experiment was conducted at Alhassa Oasis (25° 22′ N' latitude; 49°34′ E longitude) and altitude is 179 m a.s.l , Kingdom of Saudi Arabia. Treatments included the following Isoprothiolane (IPT) concentrations incorporated at the bottom of offshoot hole: control (without IPT), 25g, 50g, 75g, 100g, 200g and 500g / offshoot hole. The offshoots weight ranged between 25 – 30 kg. The IPT concentrations of 75 and 100 g/ offshoot hole seemed to be quite optimal for improving rooting of date palm offshoots. The best rooting percentage, length of root, root fresh and dry weights were obtained under 75 and 100 g/ offshoot whole IPT concentrations. Offshoots under the control and the lowest and highest IPT treatments reflected poor rooting ability. The chlorophyll content data although looked relatively similar between treatments, a slight edge of 75 and 100 g/ offshoot hole was noticeable. This relative edge might have played a significant role in the photosynthetic ability of offshoots. The efficiency of rooting of offshoots under both concentrations might have resulted from their edged photosynthetic ability

Application of Li-, Mg-, Ba-, Sr-, Ca-, and Sn-doped ceria for solar-driven thermochemical conversion of carbon dioxide

The redox reactivity of the Li-, Mg-, Ca-, Sr-, Ba-, and Sn-doped ceria (Ce0.9A0.1O2−δ) toward thermochemical CO2 splitting is investigated. Proposed Ce0.9A0.1O2−δ materials are prepared via co-precipitation of the hydroxide technique. The composition, morphology, and the average particle size of the Ce0.9A0.1O2−δ materials are determined by using suitable characterization methods. By utilizing a thermogravimetric analyzer setup, the long-term redox performance of each Ce0.9A0.1O2−δ material is estimated. The results obtained indicate that all the Ce0.9A0.1O2−δ materials are able to produce steady amounts of O2 and CO from cycle 4 to cycle 10. Based on the average nO2 released and nCO produced, the Ce0.899Sn0.102O2.002 and Ce0.895Ca0.099O1.889 are observed to be the top and bottom-most choices. When compared with the CeO2 material, all Ce0.9A0.1O2−δ materials showed elevated levels of O2 release and CO production