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181.
Carbon encapsulated iron nanoparticles(CEINPs) with very thin shells and good core-shell structures were prepared by DC arc discharge at argon intake temperature(AIT) of 800 ℃. The results of high resolution transmission electron microscope(HRTEM), energy dispersive X-ray(EDX) spectroscope, X-ray diffraction(XRD), and X-ray photoelectron spectroscope(XPS) characterizations on the product B show that the thickness of the carbon shells of CEINPs in the product B is in the range of ca. 0.5—5.3 nm, i. e., which can be as thin as only two layers of graphite. The average diameter of the CEINPs is about 24. 7 nm. The total content of Fe element in the product B is 77.0 wt%. The saturation magnetization(Ms) and coercivity(Hc) of the product B are 107.4 emu/g and 143 Oe, respectively. The formation of the CEINPs in the product B is discussed briefly. 相似文献
182.
In this paper, silt sediment is considered to be Bingham body, which is made up of coarse and fine particles in front of a hydraulic gate. The coarse and fine particles provide friction and shear stress in the course of opening the gate. They constitute together the adhesion force of the sediment. Based on this viewpoint, this paper puts forward a formula for the effect of silt sediment on the lifting force. The formula includes gate weight, down-suction force, sealing rubber friction, plus-weight, water-column pressure, plus-silted-sediment weight and rolling (or sliding)-bearing friction. Finally, the verification results show that the formula has certain reliability and the calculation accuracy can meet the need of practical engineering. 相似文献
183.
A neuro-space mapping(Neuro-SM) for modeling heterojunction bipolar transistor(HBT) is presented, which can automatically modify the input signals of the given model by neural network. The novel Neuro-SM formulations for DC and small-signal simulation are proposed to obtain the mapping network. Simulation results show that the errors between Neuro-SM models and the accurate data are less than 1%, demonstrating that the accurcy of the proposed method is higher than those of the existing models. 相似文献
184.
The Bacillus strain BH072 isolated from a honey sample showed strong antifungal activity against phytopathogen. Gene cloning test demonstrated that the strain had a tasA gene encoding an antifungal TasA protein. Although the wild strain simultaneously produced various antifungal substances, only the physicochemical property and antifungal activity of TasA protein were unclear due to the difficulty in extraction. In this study, tasA gene encoding the protein from Bacillus sp. BH072 was amplified by using the polymerase chain reaction (PCR) method and cloned into pET 28a (+) vector, and then expressed in host cells Escherichia coli BL21 (DE3). The expressed proteins were collected by centrifugation and ultrasonic treatment, and then purified by using nickel-nitrilotriacetic acid (Ni-NTA) metal affinity column and dialysis methods. The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) test showed that an expected protein band appeared with a size of 31 kDa. The expressed products possessed antifungal activity against the phytopathogenic indicator strain Botrytis cinerea. A genetically engineered strain tasA of E. coli was established in this study which can efficiently express Tas A protein. 相似文献
185.
186.
Mikyong?Kim-GohEmail author Hyunmi?Choi Myeong?Sook?Yoon 《International journal for the advancement of counseling》2015,37(1):63-76
Research has consistently found acute mental health treatment disparities among Asian Americans. One proposed reason for the underutilization of mental health services by Asian Americans is that available services are not culturally competent. This exploratory study presents qualitative data gathered from interviews with professional counselors who serve Asian American clients. Findings revealed significant barriers to counseling due to cultural stigma and shame, suppression of emotions, and communication gaps between clients and counselors. In response, clinicians frequently made adjustments to therapeutic approaches to accommodate the cultural beliefs and practices of clients and families. Implications for practice and research are discussed. 相似文献
187.
Donald Simpson Eunice Lumsden Rory McDowall Clark 《Early Years: An International Journal of Research and Development》2015,35(1):96-109
The global rise of a neoliberal ‘new politics of parenting’ discursively constructs parents in poverty as the reason for, and remedy to, child poverty. This allows for Early Childhood Education and Care (ECEC) to become a key policy lever by using human technologies to intervene in and regulate the lives of parents and children in poverty. The article explores the uptake of this policy locally through interviews with 30 ECEC practitioners in three locations across England. The interviews suggested that the neoliberal discursive formation of child poverty as a problem of the poor themselves had symbolic power and was a view shared by most of the interviewees. This appeared to restrict their thinking and action, shaping a limited engagement with parents in poverty. Delivering curricular requirements was seen to further delimit practitioners’ practices with children in poverty by reducing their poverty sensitivity. Although this is a small study, its findings may be of value in questioning neoliberal logics, and their implications are considered critically. 相似文献
188.
Bullying has been the topic of much debate and empirical investigations over the past decade. Contemporary literature contends that students with disabilities may be overrepresented within the bullying dynamic as both perpetrators and victims. Unfortunately, prevalence rates associated with the representation of students with disabilities is limited due to measurement, disability status identification, and definition issues. The present study attempted to address these issues by assessing the prevalence rates of specific subgroups of students with disabilities in a large‐scale cross‐sectional study with 13,325 students without disabilities and 1,183 students with disabilities in Grades 6 through 12. Results suggest that overall, students with disabilities reported proportionally higher rates of bullying, fighting, relational aggression, victimization, online victimization, and relational victimization than did their peers without disabilities. These findings suggest that schools must begin to establish targeted interventions to support skill development based on characteristics associated with specific disability identification. 相似文献
189.
Clare Carruthers Brenda McCarron Peter Bolan Adrian Devine Una McMahon-Beattie Amy Burns 《Assessment & Evaluation in Higher Education》2015,40(3):352-370
This study aims to ascertain student and staff attitudes to and perceptions of audio feedback made available via the virtual learning environment (VLE) for summative assessment. Consistent with action research and reflective practice, this study identifies best practice, highlighting issues in relation to implementation with the intention of redesigning activities in the light of the findings. It utilises four case studies where audio feedback was provided to students using the Wimba voice authoring tool within Blackboard Learn+ for various types of summative assessment. The intention was to identify how and in what context audio feedback via the VLE is effective and why. The research was undertaken via a combination of techniques, including a student survey and staff reflective logs. The findings indicate that students liked the convenience, effectiveness, flexibility and personalised nature of this feedback, but raised concerns with some aspects of the technology. This paper also makes practical recommendations for the use of the feedback mechanism, focusing on the most effective use of the digital medium, and highlights directions for future research. 相似文献
190.
The scientific performance of 64 political science, sociology and marketing departments in Romania is investigated with the aid of the g-index. The assessment of departments based on the g-index shows, within each of the three types of departments that make up the population of the study, a strong polarisation between top performers (very few) and weak performers (much more numerous). This alternative assessment is also found to be largely consistent with an official ranking of departments carried out in 2011 by the Ministry of Education. To conduct the evaluation of departments the individual scientific output of 1385 staff members working in the fields of political science, sociology and marketing is first determined with the aid of the ‘Publish or Perish’ software based on the Google Scholar database. Distinct department rankings are then created within each field using a successive (second-order) g-index. 相似文献