2,454 research outputs found

    Towards Low-Threshold, Real-Time Solar Neutrino Detectors

    Get PDF
    We discuss an alternative approach to the detection of solar neutrinos using a coarsely segmented detector based on inverse-beta decay onto 160^{160}Gd or 176^{176}Yb. While it is know that similar approaches, already discussed in the literature, can in principle provide low-threshold, real-time energy spectroscopy with intrinsic background rejection features, the concepts presented here make this scheme possible with lower background and current technology.Comment: 10 pages, 2 figure

    Disordered materials for high-performance lithium-ion batteries: A review

    Get PDF
    Disordered materials (DMs) have become promising materials in the advancement of lithium-ion batteries (LIBs). Their disordered, open structure is conductive to facilitate efficiency lithium-ion storage. DMs with tunable compositions also possess abundant defects that can interact with Li+, further enhancing their electrochemical performances in LIBs. Yet, revealing the structural origin of the superior electrochemical properties of DM-based LIBs remains a challenge. In this article, we review recent advances in the development of DM-based components for LIBs, such as anodes, cathodes, coating layers, and solid-state electrolytes. We give an overview on the primary methods utilized in preparing and characterizing DMs, while also describing the mechanisms involved in DM synthesis. This review article also addresses the correlation between the structural properties of DMs and their electrochemical performances. Moreover, we elucidate the challenges and future perspectives in the advancement of DM-based LIBs. We outline the key advantages of DMs in enhancing LIB performance over their crystalline counterparts, providing insights for developing superior LIBs through tailored DM development.</p

    Factors related with CH4 and N2O emissions from a paddy field : clues for management implications

    Get PDF
    Paddy fields are major sources of global atmospheric greenhouse gases, including methane (CH₄) and nitrous oxide (N₂O). The different phases previous to emission (production, transport, diffusion, dissolution in pore water and ebullition) despite well-established have rarely been measured in field conditions. We examined them and their relationships with temperature, soil traits and plant biomass in a paddy field in Fujian, southeastern China. CH₄ emission was positively correlated with CH₄ production, plant-mediated transport, ebullition, diffusion, and concentration of dissolved CH₄ in porewater and negatively correlated with sulfate concentration, suggesting the potential use of sulfate fertilizers to mitigate CH₄ release. Air temperature and humidity, plant stem biomass, and concentrations of soil sulfate, available N, and DOC together accounted for 92% of the variance in CH₄ emission, and Eh, pH, and the concentrations of available N and Fe³⁺, leaf biomass, and air temperature 95% of the N₂O emission. Given the positive correlations between CH4 emission and DOC content and plant biomass, reduce the addition of a carbon substrate such as straw and the development of smaller but higher yielding rice genotypes could be viable options for reducing the release of greenhouse gases from paddy fields to the atmosphere

    PENGGUNAAN BAHAN AJAR DALAM PEMBELAJARAN IPS SMP BERBASIS KONTEKSTUAL PADA SISWA KELAS VII SMP NEGERI 1 PURWANTORO WONOGIRI

    Get PDF
    This research aim: 1. Describe how teacher use the teaching material in Social Subject in Junior High School 1 Purwantoro up until now. 2. Describe the constraint and how to overcome it. 3. Describe the usage result of the teaching material in study of Social for Junior High School in Purwantoro 1 Junior High School. This research takes place in Purwantoro 1 Junior High School, Wonogiri Regency. This research metod is descriptive research of qualitative. This research wants to describe and expose the usage of teaching material in study of Contextual Based Social for Junior High School in Purwantoro 1 Junior High School according to the condition and the situation at the moment. Strategies utilized in this research are interviewing, question airing, observing, and documenting. The result of this research concludes that teaching material in Study of Contextual Based Social for Junior High School in Purwantoro 1 Junior High School, evaluated from its form covered : a). Printed teaching material consist. b). Heard Teaching Material (audio) consist. c) Visual and Listening Teaching Material consist. d). Interactive teaching material like compact disc (doesn’t yet able to be executed) e). Environment teaching material (geography, history, and economics) still applied in class theory level. Current result achieved from the use of teaching materials in learning of Social for Junior High School in Purwantoro Junior High School are: 1) Provide better learning environment for teachers and students. 2) Help students and make them easy to learn Social. 3) Improve student’s learning achievement proved with 79,895 average score (it exceeds current KKM set by the teachers: 72) Keywords : The Use of, Teaching Materials of Contextual Based Social for Junior High School

    Prognostic significance of nm23-H1 expression in oral squamous cell carcinoma

    Get PDF
    Recent studies indicated nm23-H1 played a role in cancer progression. Therefore, we investigated clinical significance of nm23-H1 expression in oral squamous cell carcinoma (OSCC). In total, 86 OSCC specimens were immunohistochemically stained with nm23-H1-specific monoclonal antibodies. Immunohistochemical staining of nm23-H1 was confirmed by immunoblotting. The relations between nm23-H1 expression and clinicopathologic variables were evaluated by chi(2) analysis. As increased size of primary tumour could escalate metastatic potential and the data of patients at the late T stage might confound statistical analyses, we thus paid special attention to 54 patients at the early T stage of OSCC. Statistical difference of survival was compared by a log-rank test. Immunohistochemically, nm23-H1 expression was detected in 48.8% (42 out of 86) of tumorous specimens. It positively correlated with larger primary tumour size (P = 0.03) and inversely with cigarette-smoking habit (P = 0.042). In patients at the early T stage, decreased nm23 expression was associated with increased incidence of lymph node metastasis (P = 0.004) and indicated poor survival (P = 0.014). Tumour nm23-H1 expression is a prognostic factor for predicting better survival in OSCC patients at the early T stage, which may reflect antimetastatic potential of nm23. Therefore, modulation of nm23-H1 expression in cancer cells can provide a novel possibility of improving therapeutic strategy at this stage. In addition, our results further indicated cigarette smoking could aggravate the extent of nm23-H1 expression and possibly disease progression of OSCC patients. (C) 2004 Cancer Research UK

    Effects of steel slag application on greenhouse gas emissions and crop yield over multiple growing seasons in a subtropical paddy field in China

    Get PDF
    Asia is responsible for over 90% of the world's rice production and hence plays a key role in safeguarding food security. With China being one of the major global producers and consumers of rice, achieving a sustainable balance in maximizing crop productivity and minimizing greenhouse gas emissions from paddy fields in this country becomes increasingly important. This study examined the effects of applying steel slag, a residual product derived from the steel industry, on crop yield and CH4 and N2O emissions over multiple growing seasons in a Chinese subtropical paddy field. Average CH4 emission was considerably higher during the periods of rice crop growth compared to that during the periods of fallowing and vegetable crop growth, regardless of the amount of steel slag applied. When compared to the controls, significantly lower mean emissions of CH4 (1.03 vs. 2.34 mg m−2 h−1) and N2O (0.41 vs. 32.43 μg m−2 h−1) were obtained in plots with slag addition at a rate of 8 Mg ha−1 over the study period. The application of slag at 8 Mg ha−1 increased crop yields by 4.2 and 9.1% for early and late rice crops, respectively, probably due to the higher availability of inorganic nutrients such as silicates and calcium from the slag. Slag addition had no significant effect on the concentrations of heavy metals in either the soil or the rice grains, although a slight increase in the levels of manganese and cobalt in the soil and a decrease in the levels of manganese and zinc in the rice grains were observed. Our results demonstrate the potential of steel slag as a soil amendment in enhancing crop yield and reducing greenhouse gas emissions in subtropical paddy fields in China, while posing no adverse short-term impacts on the concentrations of heavy metals in the soil or the rice grains. However, long-term implications of this management practice and the cost/benefit remain unknown, so further studies to assess the suitability at large scale are warranted

    Probabilistic Simulation of Shape Instability Based on the True Microstructure Model

    No full text
    Shape instability belongs to one of significant types of violation for disposable structural elements under high-stress levels. Due to lack of fundamental data on materials, it is quite problematic to consider the shape instability in the design of disposable structural elements. The crystal plastic finite element method is proposed to investigate the dispersion of shape instability life data. It allows these data to be obtained from traditional material parameters. The shape instability behavior is described with the constitutive crystal model of plastic damage accumulation. Then, to improve the accuracy of life prediction, the new method is developed to construct the simulation model of true microstructure. A modeling algorithm based on the image processing technology is provided to reduce the virtual stresses from the transient crystal plastic modeling method. Comparison of experimental and predicted results shows good agreement at high stresses close to the elastic limit of the material.Одним из видов потери устойчивости является формоизменение элементов конструкции одноразового применения при высоких уровнях напряжений. Отсутствие основных данных о материалах не позволяет учесть этот параметр при их проектировании. Предложен метод конечных элементов в пластической постановке для оценки разброса данных о сроке службы элемента при его формоизменении. Для этого могут быть использованы традиционные параметры материала. Характер формоизменения описывается с помощью определяющей модели накопления пластических повреждений на кристалле. Разработан новый метод построения имитационной модели реальной микроструктуры с целью повышения точности прогнозирования срока службы. Моделирующий алгоритм, основанный на технологии обработки изображения, позволяет уменьшить эффект виртуальных напряжений при применении нестационарного метода пластического моделирования на кристалле. Сравнение экспериментальных и расчетных данных демонстрирует их хорошее соответствие при высоких напряжениях, близких к пределу упругости материала

    Contributions of dry and wet depositions of polychlorinated dibenzo-p-dioxins and dibenzofurans to a contaminated site resulting from a penetachlorophenol manufacturing process

    Get PDF
    The soils at a factory for manufacturing pentachlorophenol were heavily contaminated by polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). In order to verify the contributions of dry and wet deposition of PCDD/Fs from the ambient air, the concentration of PCDD/Fs in ambient air and soil were measured, the partition of particle- and gas-phases of atmospheric PCDD/Fs was calculated, and the annual fluxes of total dry and wet PCDD/F depositions were modeled. Average atmospheric PCDD/F concentration was 1.24 ng Nm (-aEuro parts per thousand 3) (or 0.0397 ng I-TEQ Nm (-aEuro parts per thousand 3)). Moreover, over 92.8% of total PCDD/Fs were in the particle phase, and the dominant species were high chlorinated congeners. The total PCDD/F fluxes of dry and wet deposition were 119.5 ng m (-aEuro parts per thousand 2) year (-aEuro parts per thousand 1) (1.34 ng I-TEQ m (-aEuro parts per thousand 2) year (-aEuro parts per thousand 1)) and 82.0 ng m (-aEuro parts per thousand 2) year (-aEuro parts per thousand 1) (1.07 ng I-TEQ m (-aEuro parts per thousand 2) year (-aEuro parts per thousand 1)), respectively. By scenario simulation, the total fluxes of dry and wet PCDD/F depositions were 87.1 and 68.6 ng I-TEQ, respectively. However, the estimated PCDD/F contents in the contaminated soil were 839.9 mu g I-TEQ. Hence, the contributions of total depositions of atmospheric PCDD/F were only 0.02%. The results indicated that the major sources of PCDD/F for the contaminated soil could be attributed to the pentachlorophenol manufacturing process
    corecore