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991.
J. Y. Wang Y. Cao Y. Feng F. Yin J. P. Gao 《Advanced materials (Deerfield Beach, Fla.)》2007,19(22):3865-3871
992.
纺锤体流量计的流场数值模拟 总被引：2，自引：0，他引：2
介绍了一种新型的节流式差压流量计——纺锤体流量计（又名槽道流量计）。数值模拟结果表明,在来流规则或畸变情况下纺锤体等直径段部分均能很好地形成环形槽道流动,使测量重复性和精确度得到大幅提高成为可能;同时,由于完全避免了流动分离,在高雷诺数下的压力损失与所得差压之比可小于孔板流量计的二分之一。实验结果验证了数值模拟的可靠性。 相似文献
993.
Li H Yin Z He Q Li H Huang X Lu G Fam DW Tok AI Zhang Q Zhang H 《Small (Weinheim an der Bergstrasse, Germany)》2012,8(1):63-67
Single- and multilayer MoS(2) films are deposited onto Si/SiO(2) using the mechanical exfoliation technique. The films were then used for the fabrication of field-effect transistors (FETs). These FET devices can be used as gas sensors to detect nitrous oxide (NO). Although the single-layer MoS(2) device shows a rapid response after exposure to NO, the current was found to be unstable. The two-, three-, and four-layer MoS(2) devices show both stable and sensitive responses to NO down to a concentration of 0.8 ppm. 相似文献
994.
995.
Dou G Holmes AS Yeatman EM Wright RV Kirby PB Yin C 《Advanced materials (Deerfield Beach, Fla.)》2011,23(10):1252-1256
996.
997.
998.
Jinyou Xiao Wenjing Ye 《International journal for numerical methods in engineering》2011,88(7):693-714
This paper describes a new wavelet boundary element method (WBEM) for large‐scale simulations of three‐dimensional Stokes problems. It is based on a Galerkin formulation and uses only one set of wavelet basis. A method for the efficient discretization and compression of the double‐layer integral operator of Stokes equation is proposed. In addition, a compression strategy for further reducing the setting‐up time for the sparse system matrix is also developed. With these new developments, the method has demonstrated a high matrix compression rate for problems with complicated geometries. Applications of the method are illustrated through several examples concerning the modeling of damping forces acting on MEMS resonators including a cantilever resonator oscillating in an unbounded air and a perforated plate resonator oscillating next to a fixed substrate. The numerical results clearly illustrate the efficiency and accuracy of the developed WBEM in these large‐scale Stokes flow simulations. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
999.
Chertow GM Lu ZJ Xu X Knight TG Goodman WG Bushinsky DA Block GA 《Hemodialysis international. International Symposium on Home Hemodialysis》2012,16(2):188-197
Patients with secondary hyperparathyroidism experience a variety of clinical symptoms which may adversely affect physical and mental function. As part of a multicenter, open-label clinical trial, subjects completed a questionnaire that included the Medical Outcomes Study Short Form-36 and 14 kidney disease-related symptoms at multiple time points during the study. Out of the 567 subjects who received at least one dose of cinacalcet, 528 to 535 (93.8-94.4%) completed all or portions of the questionnaire at baseline. The median bioactive parathyroid hormone (PTH) was 294 pg/mL (10%, 90% range, 172-655 pg/mL). Following treatment with cinacalcet and low-dose vitamin D sterols, subjects reported significant improvement in the frequency of pain in muscles, joints and bones, stiff joints, dry skin, itchy skin, excessive thirst, and trouble with memory. At end of the efficacy assessment phase (Weeks 16 to 22), the magnitude of improvement was the greatest in joint pain, bone pain, dry skin, and excessive thirst (>5 on a 0-100 scale; P < 0.001). There were no clinically or statistically significant changes in any of the Short Form-36 subscales or in the physical or mental health composite scores. Among patients on hemodialysis with moderate to severe secondary hyperparathyroidism, treatment with cinacalcet and low-dose vitamin D sterols results in significant improvement in pain in the muscles, joints and bones, joint stiffness, dry and itchy skin, excessive thirst, and trouble with memory. 相似文献
1000.
Zhu M Tian X Song X Li Y Tian Y Zhao Y Nie G 《Small (Weinheim an der Bergstrasse, Germany)》2012,8(18):2841-2848
The mechanisms associated with the induction of systemic immune responses by nanoparticles are not fully understood, but their elucidation is critical to address safety issues associated with the broader medical application of nanotechnology. In this study, a key role of nanoparticle-induced exosomes (extracellularly secreted membrane vesicles) as signaling mediators in the induction of T helper cell type 1 (Th1) immune activation is demonstrated. In vivo exposure to magnetic iron oxide nanoparticles (MIONs) results in significant exosome generation in the alveolar region of Balb/c mice. These act as a source of nanoparticle-induced, membrane-bound antigen/signaling cargo, which transfer their components to antigen-presenting cells (APCs) in the reticuloendothelial system. Through exosome-initiated signals, immature dendritic cells (iDCs) undergo maturation and differentiation to the DC1 subtype, while macrophages go through classical activation and differentiation to the M1 subtype. Simultaneously, iDCs and macrophages release various Th1 cytokines (including interleukin-12 and tumor necrosis factor α) driving T-cell activation and differentiation. Activated APCs (especially DC1 and M1 subtypes) consequently prime T-cell differentiation towards a Th1 subtype, thereby resulting in an orchestrated Th1-type immune response. Th1-polarized immune activation is associated with delayed-type hypersensitivity, which might underlie the long-term inflammatory effects frequently associated with nanoparticle exposure. These studies suggest that nanoparticle-induced exosomes provoke the immune activation and inflammatory responses that can accompany nanoparticle exposure. 相似文献