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51.
Cover Picture: Time‐Dependent Diaryl Ether Inhibitors of InhA: Structure–Activity Relationship Studies of Enzyme Inhibition,Antibacterial Activity,and in vivo Efficacy (ChemMedChem 4/2014) 下载免费PDF全文
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53.
Red Blood Cell Membrane as a Biomimetic Nanocoating for Prolonged Circulation Time and Reduced Accelerated Blood Clearance 下载免费PDF全文
Lang Rao Lin‐Lin Bu Jun‐Hua Xu Bo Cai Guang‐Tao Yu Xiaolei Yu Zhaobo He Qinqin Huang Andrew Li Shi‐Shang Guo Wen‐Feng Zhang Wei Liu Zhi‐Jun Sun Hao Wang Tza‐Huei Wang Xing‐Zhong Zhao 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(46):6225-6236
For decades, poly(ethylene glycol) (PEG) has been widely incorporated into nanoparticles for evading immune clearance and improving the systematic circulation time. However, recent studies have reported a phenomenon known as “accelerated blood clearance (ABC)” where a second dose of PEGylated nanomaterials is rapidly cleared when given several days after the first dose. Herein, we demonstrate that natural red blood cell (RBC) membrane is a superior alternative to PEG. Biomimetic RBC membrane‐coated Fe3O4 nanoparticles (Fe3O4@RBC NPs) rely on CD47, which is a “don't eat me” marker on the RBC surface, to escape immune clearance through interactions with the signal regulatory protein‐alpha (SIRP‐α) receptor. Fe3O4@RBC NPs exhibit extended circulation time and show little change between the first and second doses, with no ABC suffered. In addition, the administration of Fe3O4@RBC NPs does not elicit immune responses on neither the cellular level (myeloid‐derived suppressor cells (MDSCs)) nor the humoral level (immunoglobulin M and G (IgM and IgG)). Finally, the in vivo toxicity of these cell membrane‐camouflaged nanoparticles is systematically investigated by blood biochemistry, hematology testing, and histology analysis. These findings are significant advancements toward solving the long‐existing clinical challenges of developing biomaterials that are able to resist both immune response and rapid clearance. 相似文献
54.
Even though oil palm (Elaeis quineensis) stem (OPS) is highly potential as an alternative raw material in wood industry, it possesses some inferior characteristics. One of the critical weaknesses is a high degree of veneer surface roughness that resulted in high resin consumption during plywood manufacture. The objective of this study was to investigate effects of treatment with low molecular weight phenol formaldehyde (LMWPF) resin on the wettability and surface roughness of OPS veneer. OPS veneers were segregated into two categories namely outer and inner layer veneer, prior to soaking in LMWPF resin solution to obtain weight percent gain of 16–20%. The wettability of OPS veneers was assessed with contact angle measurement according to the sessile drop method. The veneer surface roughness was evaluated by determining the average roughness (Ra), mean peak-to-valley height (Rz), and maximum roughness (Rmax) using a stylus profilometer in accordance with DIN standard 4768. The results show that the effect of LMWPF resin treatment on the surface roughness of the veneers is statistically significant. The technique used in the study was able to enhance the surface properties as well as improved the physical and mechanical properties of OPS plywood. 相似文献
55.
Power management strategy is as significant as component sizing in achieving optimal fuel economy of a fuel cell hybrid vehicle (FCHV). We have formulated a combined power management/design optimization problem for the performance optimization of FCHVs. This includes subsystem-scaling models to predict the characteristics of components of different sizes. In addition, we designed a parameterizable and near-optimal controller for power management optimization. This controller, which is inspired by our stochastic dynamic programming results, can be included as design variables in system optimization problems. Simulation results demonstrate that combined optimization can efficiently provide excellent fuel economy. 相似文献
56.
Xizu Wang Jian Wei Ho Qingyi Yang Hoi Lam Tam Gui Xin Li Kok Wai Cheah Furong Zhu 《Organic Electronics》2011,12(11):1943-1947
In this work, Ag nanoparticles were modified by an ultra-thin plasma-polymerized fluorocarbon film (CFX) to form a composite CFX-modified Ag nanoparticles/indium tin oxide (ITO) anode for application in organic photovoltaic (OPV) devices. A CFX-modified Ag nanoparticles/ITO anode exhibited a superior surface work function of 5.4 eV suited for application in OPV devices. The performance of zinc phthalocyanine:fullerene-based OPV devices showed a significant improvement when the structural identical cells are made with the CFX-modified Ag nanoparticles/ITO. This work yielded a promising power conversion efficiency of 3.5 ± 0.1%, notably higher than that with a bare ITO anode (2.7 ± 0.1%). 相似文献
57.
This paper investigates the feasibility of dry erosion by blasting alumina erodent on aluminum composite reinforced with silicon carbide particles. The erosion rate is dependent on the erodent velocity and the matrix hardness. Two different material removal mechanisms are observed due to different attack angles. Blasting between 30-60° is recommended for optimum erosion rate and surface quality. Material removal mechanisms and surface quality of blasted and ground composites are compared. Although its erosion rate is two orders of magnitude less than that for rough grinding, dry blasting is suitable as a finishing process of composites with irregular contours. 相似文献
58.
本文对多晶硅膜离子注入掺杂和扩散掺杂制备浅发射结进行了实验研究。针对新型薄发射极晶闸管特性改善对薄发射极参数的要求,重点研究了采用不同方法时退火条件对薄发射区掺杂剖面、结深以及杂质总量的影响。管芯研究结果表明,在适当的退火条件下,离子注入掺杂制备浅结是改善器件特性较为理想的方法。 相似文献
59.
A linear stability analysis for the ferrofluid flow between two concentric rotating cylinders in the presence of an axial magnetic field is implemented in this study. Both of the wide-gap and small-gap cases are considered and the governing equations with respect to three-dimensional disturbances including axisymmetric and non-axisymmetric modes are derived and solved by a direct numerical procedure. A parametric study covering wide ranges of ?, the volume fraction of colloidal particles; ξ, the strength of axial magnetic field; μ, the ratio of angular velocity of the outer cylinder to that of the inner cylinder; and ε, the ratio of radius of the inner cylinder to that of the outer cylinder, is conducted. Results show that the stability characteristics depend heavily on these factors. It is found that the increases of ? and ξ, and decrease of ε tend to stabilize the basic flow for an assigned value of μ. The variations of the onset mode with these parameters are discussed in detail. An example for the practical application of present results is given to help the understanding of stability behaviour of this flow. 相似文献
60.
Zuo-Min Tsai Mei-Chao Yeh Hong-Yeh Chang Ming-Fong Lei Lin K.-Y. Chin-Shen Lin Huei Wang 《Microwave Theory and Techniques》2006,54(5):2090-2097
A new transmission-line concept, called the field-effect transistor (FET)-integrated coplanar waveguide (CPW), is proposed. This concept treats the passive two-finger FET as CPW and, thus, the scaling rule is more accurate than the previous model, especially in high frequency. The extraction approach of the parameters of the FET-integrated CPW is also included. With this concept, the design procedure of traveling-wave switches can be equivalent to a filter synthesis problem. Based on this design procedure, a single-pole single-throw and a single-pole double-throw traveling-wave switch have been realized and measured using 0.15-/spl mu/m high-linearity AlGaAs/InGaAs/GaAs pseudomorphic high electron-mobility transistors. Finally, the frequency limitation of the traveling-wave switches is also discussed. The results show the FET-integrated CPW is the most efficient way to overcome the frequency limitations of traveling-wave switches, achieving operation frequency to 135 GHz, the highest frequency reported to date. 相似文献