Long-term mechanical behavior of Yucca Mountain tuff and its variability

The study of the long term mechanical behavior of Yucca Mountain tuffs is important for several reasons. Long term stability of excavations will affect accessibility (e.g. for inspection purposes), and retrievability. Long term instabilities may induce loading of drip shields and/or emplaced waste, thus affecting drip shield and/or waste package corrosion. Failure of excavations will affect airflow, may affect water flow, and may affect temperature distributions. The long term mechanical behavior of “hard” rocks remains an elusive topic, loaded with uncertainties. A variety of approaches have been used to improve the understanding of this complex subject, but it is doubtful that it has reached a stage where firm predictions can be considered feasible

Simulation analysis of crack cause of concrete overflow dam for Hadashan Hydro Project by 3-D FEM

AbstractThis paper is mainly to study the cracking reasons for concrete overflow dam of Hadashan Hydro Project. The three-dimensional finite element method (3-D FEM) is developed to simulation analysis the temperature and thermal stress distribution in the concrete overflow dam during the construction period. The results show that the crack of the concrete overflow dam is temperature crack, mainly due to the combined action of the internal thermal gradient and the external restraints; and dramatic changes in ambient temperature exacerbate cracking of early-age concrete. Finally, the results are applied to provide some references for the construction in the related fields

Preparation of supported skeletal Ni catalyst and its catalytic hydrogenation performance of C9 fraction from coking process

Currently, the inferior compressive strength of traditional Raney-Ni catalyst restricts its application in fixed-bed reactor. To approach this problem a series of supported skeletal Ni catalysts were prepared by mixing pseudo boehmite and Ni-Al alloy powder. In the process,the calcination temperature and atmosphere, mass ratio of pseudo boehmite to Ni-Al alloy powder and the sodium hydroxide solution concentration were investigated. The catalysts characterized by intelligent granule intensity tester(IGIT), scanning electron microscopy(SEM), X-ray photoelectron spectroscopy(XPS), X-ray diffraction (XRD),low temperature nitrogen adsorption, temperature programmed reduction of hydrogen (H2-TPR), and thermogravimetric-differential thermal analysis (TG-DTA).The results were shown that the calcination atmosphere had a considerable impact on the compressive strength of the catalyst. Compared with air atmosphere, the compressive strength of the catalyst increased from 12.62 N/mm to 23.96N/mm, obviously, in argon atmosphere, which was almost twice as much as the former.The inherent reason for this was that the argon obviously inhibited the transform of NiAl3 to Ni2Al3 in which the latter was the key factor to improve compressive strength. Additionally, coke-oven C9 hydrogenation was used to evaluate the performance of the catalyst and the results indicated that the conversion of indene, the key component of coke-oven C9, was as high as 90% in 1000h under the optimum reaction conditions:T=220oC, P(H2)=2.5MPa, H2/oil=200(v/v), LHSV=3.0h-1. Our data demonstrated that the supported skeletal Ni catalyst have a good industrial prospect in the fixed-bed reactor in future

Soy 11S Globulin Acid Subunits as the Novel Food Polymer Carrier

Aflatoxins were conjugated with soy 11S globulins acid subunits and the hapten-specific monoclonal antibodies (McAbs) cross-reactive with four major aflatoxins were achieved using indirect competitive ELISA screening procedure. The two antibodies (clones 1B2 and 2D3) had similar reaction efficiency with aflatoxins B1, B2, and G1 but showed a weak cross-reaction to G2. The clone 4C5 exhibited the highest sensitivity for all four aflatoxins. The concentrations of aflatoxins B1, B2, G1, and G2 at 50% inhibition for 4C5 were 1.1, 1.2, 2.1, and 17.6 pg mL−1. The results indicated that soy 11S globulin acid subunits were suitable novel carriers for aflatoxin antigen in immunization experiments and clone 4C5 could be used for simultaneous analysis of total aflatoxins

RNA-Seq analysis identifies key genes associated with haustorial development in the root hemiparasite Santalum album

Santalum album (sandalwood) is one of the economically important plant species in the Santalaceae for its production of highly valued perfume oils. Sandalwood is also a hemiparasitic tree that obtains some of its water and simple nutrients by tapping into other plants through haustoria which are highly specialized organs in parasitic angiosperms. However, an understanding of the molecular mechanisms involved in haustorium development is limited. In this study, RNA sequencing (RNA-seq) analyses were performed to identify changes in gene expression and metabolic pathways associated with the development of the S. album haustorium. A total of 56,011 non-redundant contigs with a mean contig size of 618 bp were obtained by de novo assembly of the transcriptome of haustoria and non-haustorial seedling roots. A substantial number of the identified differentially expressed genes were involved in cell wall metabolism and protein metabolism, as well as mitochondrial electron transport functions. Phytohormone-mediated regulation might play an important role during haustorial development. Especially, auxin signaling is likely to be essential for haustorial initiation, and genes related to cytokinin and gibberellin biosynthesis and metabolism are involved in haustorial development. Our results suggest that genes encoding nodulin-like proteins may be important for haustorial morphogenesis in S. album. The obtained sequence data will become a rich resource for future research in this interesting species. This information improves our understanding of haustorium development in root hemiparasitic species and will allow further exploration of the detailed molecular mechanisms underlying plant parasitism

How Students View the Role of Faculty Advisors in the SWE Organization

The Society of Women Engineers (SWE) collegiate sections attract many men and women to the society, and they can be among the largest and most active student organizations on the university campuses. A key factor to boost membership is the active involvement of faculty advisors, who serve as the liaison between SWE collegiate sections, the university, the National SWE organization, and professional SWE members. A group of SWE faculty advisors previously conducted a survey of faculty advisors and counselors, with advisors and counselors aggregated in the results, to determine what aspects of their role they consider most significant, and how they engage with the students. The study showed that faculty advisors play an important role in providing continuity to the section, participation in and understanding of the larger organization, and in mentoring students on both general leadership and SWE leadership. This paper examines how students view the role of their faculty advisor in their SWE collegiate section. The objectives of this study are to understand the challenges that collegiate sections face and what types of support they need from their faculty advisor. A survey about the level of importance of different roles of faculty advisors was conducted. Additional ways students feel their faculty advisor could help them was also addressed. The data was analyzed to identify key factors that faculty advisors should consider while serving in these roles within student sections. The findings were then compared to the results of the self-assessment of the faculty advisors