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21.
Zilla Sinuany-Stern Nachum Finger Elias Kligler 《Computers, Environment and Urban Systems》1986,11(4)
This paper provides a model for finding the optimal thinning policy in a pine forest (Pinus halepensis) in Israel. The model simulates the growth of a pine forest stand for timber, under various thinning policies. The annual growth functions are estimated via polynomial regression analysis. The dependent variable is the timber volume of the stand and the explanatory variable is the mean growing space per tree over time. The observations were made over the life span of five experimental parcels in a pine forest in Israel. 相似文献
22.
Jake D. Mehew Selim Unal Elias Torres Alonso Gareth F. Jones Saad Fadhil Ramadhan Monica F. Craciun Saverio Russo 《Advanced materials (Deerfield Beach, Fla.)》2017,29(23)
The combination of graphene with semiconductor materials in heterostructure photodetectors enables amplified detection of femtowatt light signals using micrometer‐scale electronic devices. Presently, long‐lived charge traps limit the speed of such detectors, and impractical strategies, e.g., the use of large gate‐voltage pulses, have been employed to achieve bandwidths suitable for applications such as video‐frame‐rate imaging. Here, atomically thin graphene–WS2 heterostructure photodetectors encapsulated in an ionic polymer are reported, which are uniquely able to operate at bandwidths up to 1.5 kHz whilst maintaining internal gain as large as 106. Highly mobile ions and the nanometer‐scale Debye length of the ionic polymer are used to screen charge traps and tune the Fermi level of the graphene over an unprecedented range at the interface with WS2. Responsivity R = 106 A W?1 and detectivity D* = 3.8 × 1011 Jones are observed, approaching that of single‐photon counters. The combination of both high responsivity and fast response times makes these photodetectors suitable for video‐frame‐rate imaging applications. 相似文献
23.
24.
Claudio Bernardazzi Morgana Teixeira Lima Castelo-Branco Beatriz Pêgo Beatriz Elias Ribeiro Siane Lopes Bittencourt Rosas Patrícia Teixeira Santana Joo Carlos Machado Camille Leal Fabiano Thompson Robson Coutinho-Silva Heitor Siffert Pereira de Souza 《International journal of molecular sciences》2022,23(9)
25.
Elias Pentti Juho Rysti Anssi Salmela Alexander Sebedash Juha Tuoriniemi 《Journal of Low Temperature Physics》2011,165(3-4):132-165
We present results of low-temperature experiments on dilute mixtures of 3He in 4He and on pure 3He, obtained by means of two kinds of mechanical oscillators immersed in the liquid sample: vibrating wires and quartz tuning forks. The helium sample was cooled either by adiabatic demagnetization of an immersed copper nuclear stage or by adiabatic melting of 4He in superfluid 3He. The measured effect of the surrounding fluid on the mechanical resonance of the oscillators is compared with existing theories. We also discuss resonances of second sound and the state of supersaturation, both observed by a tuning fork in helium mixtures. 相似文献
26.
Elias Salameh 《The International journal of environmental studies》2013,70(4):291-300
Two main problems seem to face the use of surface water for domestic purposes in semi‐arid regions. These problems are eutrophication of surface water bodies and the formation of chlorinated hydrocarbons during water treatment. Both problems develop as direct of indirect results of anthropogenic activities. The eutrophication problem will be discussed with reference to King Talal Reservoir, whereas the formation of chlorinated hydrocarbons will be illustrated when discussing the use of the East Ghor Canal water for domestic purposes. 相似文献
27.
Ioanna Diamandi John N. Sahalos Elias Vafiadis 《International Journal of Numerical Modelling》1993,6(2):99-108
A rigorous formulation of the scattering by a magnetized ferrite in a rectangular waveguide is presented. The EM field depends on the dimension, the frequency and the internal static magnetic field of the ferrite post. For some special values of the above quantitites the reflection or the transmission coefficient becomes equal to zero. These values give a family of filters and the results which follow explain their characteristics. 相似文献
28.
Role of physical structures in bulk oils on lipid oxidation 总被引:1,自引:0,他引:1
Chaiyasit W Elias RJ McClements DJ Decker EA 《Critical reviews in food science and nutrition》2007,47(3):299-317
Lipid oxidation is important to food manufacturers especially when they increase unsaturated lipids in their products to improve nutritional profiles. Unfortunately, the number of antioxidants available to food manufacturers to control oxidative rancidity is limited and the approval of new antioxidants is unlikely due to economic barriers in obtaining government approval for new food additives. Therefore, new antioxidant technologies are needed for food oils. This paper reviews the current knowledge of lipid oxidation in foods with emphasis on how physical properties of food systems impact oxidation chemistry. In particular, the role of association colloids in bulk oils on lipid oxidation chemistry is discussed in an attempt to understand mechanisms of oxidation. Increasing the understanding of how physical properties impact lipid oxidation could lead to the development of novel antioxidant technologies that not only protect the oil against oxidation and increase shelf-life but also allow food manufacturers to include more nutritionally beneficial fatty acids in their products. 相似文献
29.
虽然细胞分子生物学近年来发展很快,但是细胞培养的方法变化很慢.将近一个世纪以前发明的有盖培养皿至今仍在常规使用,但它已经不适合许多用来观察和分析活体细胞内发生的变化的现代光学分析方法.这篇文章描述了一种细胞培养芯片装置,它能有效地用于细胞培养和随后的高端光学分析,比如荧光和共焦显微镜方法. 相似文献
30.
Petra Pavel Stefan Blunder Verena Moosbrugger-Martinz Peter M. Elias Sandrine Dubrac 《International journal of molecular sciences》2022,23(4)
Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease in which dry and itchy skin may develop into skin lesions. AD has a strong genetic component, as children from parents with AD have a two-fold increased chance of developing the disease. Genetic risk loci and epigenetic modifications reported in AD mainly locate to genes involved in the immune response and epidermal barrier function. However, AD pathogenesis cannot be fully explained by (epi)genetic factors since environmental triggers such as stress, pollution, microbiota, climate, and allergens also play a crucial role. Alterations of the epidermal barrier in AD, observed at all stages of the disease and which precede the development of overt skin inflammation, manifest as: dry skin; epidermal ultrastructural abnormalities, notably anomalies of the lamellar body cargo system; and abnormal epidermal lipid composition, including shorter fatty acid moieties in several lipid classes, such as ceramides and free fatty acids. Thus, a compelling question is whether AD is primarily a lipid disorder evolving into a chronic inflammatory disease due to genetic susceptibility loci in immunogenic genes. In this review, we focus on lipid abnormalities observed in the epidermis and blood of AD patients and evaluate their primary role in eliciting an inflammatory response. 相似文献