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Lihua Lou Weijie Yu Ronald J. Kendall Ernest Smith Seshadri S. Ramkumar 《应用聚合物科学杂志》2020,137(30):49213
A tensile properties testing study was conducted to understand the influence of thickness, cross-head speed (speed of testing), gauge length (GL; specimen test length), and sample shape on important tensile properties of polyvinyl alcohol (PVA) nanofiber webs. The effects of each testing parameter on load at break, extension at break, Young's modulus, and tensile stress–strain curve of PVA nanofiber webs are analyzed. The Welch two sample t-tests show the significant difference among tested data. Using interaction plots, two-way analysis of variance, and margin mean plots, the interaction effects among testing parameters have been analyzed. Of all the factors, cross-head speed, the interaction among GL, and sample thickness (GL: Thickness) and the interaction among GL, testing speed and sample thickness (GL: Speed: Thickness) have significant influence on the tensile properties of PVA nanofiber webs. Moreover, the hypothesized model of mechanism of tensile strain–stress curve of PVA nanofiber webs has been proposed. Based on the model, the tensile strain–stress curve can be split into three stages: linear elastic, partial break up, and complete breakage. This study will provide a better understanding of tensile testing parameters' effects and their interaction effects on the tensile properties of nanowebs. 相似文献
13.
Guo-Yu Li Ya-Xin Zheng Fu-Zhou Sun Jian Huang Meng-Meng Lou Jing-Kai Gu Jin-Hui Wang 《International journal of molecular sciences》2015,16(9):22190-22204
This study aimed at investigating the possible mechanisms of hepatic protective activity of Cichorium intybus L. (chicory) in acute liver injury. Pathological observation, reactive oxygen species (ROS) detection and measurements of biochemical indexes on mouse models proved hepatic protective effect of Cichorium intybus L. Identification of active compounds in Cichorium intybus L. was executed through several methods including ultra performance liquid chromatography/time of flight mass spectrometry (UPLC-TOF-MS). Similarity ensemble approach (SEA) docking, molecular modeling, molecular docking, and molecular dynamics (MD) simulation were applied in this study to explore possible mechanisms of the hepato-protective potential of Cichorium intybus L. We then analyzed the chemical composition of Cichorium intybus L., and found their key targets. Furthermore, in vitro cytological examination and western blot were used for validating the efficacy of the selected compounds. In silico analysis and western blot together demonstrated that selected compound 10 in Cichorium intybus L. targeted Akt-1 in hepatocytes. Besides, compound 13 targeted both caspase-1 and Akt-1. These small compounds may ameliorate liver injury by acting on their targets, which are related to apoptosis or autophagy. The conclusions above may shed light on the complex molecular mechanisms of Cichorium intybus L. acting on hepatocytes and ameliorating liver injury. 相似文献
14.
Zhou Zhixin Shao Chenning Zheng Haonan Zhou Huimin Yang Xin Lou Xiongwei Li Jian Hui Guohua Zhao Zhidong 《Wireless Networks》2020,26(4):2797-2808
Wireless Networks - Utility tunnel is one of the important infrastructures for the planning and building of smart city. It is of great significance to improve the efficiency of maintenance and... 相似文献
15.
In this work, lignosulfonate-acrylamide-dimethyldiallylammonium chloride (LAD) terpolymer was designed and synthesized by microwave-assisted graft polymerization. The optimal synthetic process was obtained as follows: the monomer ratio was 1:4:4, the amount of initiator was 0.9% (w/w), the monomer solid content was 21 wt %, and the reaction time was 14 min with the microwave power of 280 W. Furthermore, the flocculation performance of LAD was verified by removing acid black-172 dye wastewater. At the LAD dosage of 350 mg L−1, the maximum color removal ratio reached 99.8% in 100 mg L−1 of dye wastewater. The dynamics of dye removal reached higher than 90% after 20 s. The flocculant can maintain color removal ratio more than 98% in a wide flocculant dosage and environmental pH. The flocculation mechanism was mainly electrical neutralization and bridging effect. In general, it is a promising candidate in wastewater treatment in terms of cost, synthetic method, and effectiveness. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48560. 相似文献
16.
Brian A. Jalaian Xu Yuan Yi Shi Y. Thomas Hou Wenjing Lou Scott F. Midkiff Venkat Dasari 《Wireless Networks》2018,24(7):2357-2374
Recent advances in MIMO degree-of-freedom (DoF) models allowed MIMO research to penetrate the networking community. Independent from MIMO, successive interference cancellation (SIC) is a powerful physical layer technique used in multi-user detection. Based on the understanding of the strengths and weaknesses of MIMO DoF and SIC, we propose to have DoF-based interference cancellation (IC) and SIC help each other so that (i) precious DoF resources can be conserved through the use of SIC and (ii) the stringent SINR threshold criteria can be met through the use of DoF-based IC. In this paper, we develop the necessary mathematical models to realize the two ideas in a multi-hop wireless network. Together with scheduling and routing constraints, we develop a cross-layer optimization framework with joint DoF IC and SIC. By applying the framework on a throughput maximization problem, we find that SIC and DoF IC can indeed work in harmony and achieve the two ideas that we propose. 相似文献
17.
The Journal of Supercomputing - To meet the requirements for motion estimation of a swarm of micro-aerial vehicles in a GPS-restricted environment, a distributed motion estimation algorithm is... 相似文献
18.
Journal of Mathematical Imaging and Vision - In this paper, we investigate shape inversion algorithms based on the computation of iterated topological derivatives for the detection of multiple... 相似文献
19.
Temperature/pH dual responsive microgels of crosslinked poly(N‐vinylcaprolactam‐co‐undecenoic acid) as biocompatible materials for controlled release of doxorubicin 下载免费PDF全文
Shaofeng Lou Shan Gao Weiwei Wang Mingming Zhang Qiqing Zhang Chun Wang Chen Li Deling Kong 《应用聚合物科学杂志》2014,131(23)
Undecenoic acid functionalized thermo/pH responsive microgels, poly(N‐vinylcaprolactam‐co‐undecenoic acid) [poly(VCL‐co‐UA)], were synthesized by precipitation emulsion copolymerization. The microgels exhibit reversible thermo/pH responsive phase transition behavior, which can be tuned by varying the monomer feed ratio. The lower critical solution temperatures (LCSTs) of the materials are close to body temperature. As a result, when temperatures rise above ca. 37°C, a rapid thermal gelation process occurs, accompanied by a phase transition, resulting in expulsion of encapsulated compound. In vitro experiment evaluated its applicability as a drug carrier for controlled release of an anticancer agent (doxorubicin) and showed that the drug encapsulation efficiency (EE), releasing rate, and kinetics are dependent on the temperature and pH value as expected. Minimal cytotoxicity of the microgels was observed by a cytotoxicity assay using 3T3 fibroblast cells. Our finding suggests that the poly(VCL‐co‐UA) based microgels may be considered a promising candidate for temperature or pH‐controlled delivery of anticancer drugs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41146. 相似文献
20.
Xiaojing Cheng Qian Gou Jiagang Wu Xiaopeng Wang Binyu Zhang Dingquan Xiao Jianguo Zhu Xiangjian Wang Xiaojie Lou 《Ceramics International》2014
A new phase boundary with rhombohedral–orthorhombic and orthorhombic–tetragonal phase boundaries is designed in (K0.48Na0.52)NbO3 by adding Bi0.5(Na0.7K0.2Li0.1)0.5ZrO3 (BNKLZ), where Zr4+ and (BNKL)2+ are respectively used to improve the temperature of a rhombohedral phase and to decrease the temperature of an orthorhombic–tetragonal phase coexistence. These ceramics endure several continuous phase transitions with increasing BNKLZ content, i.e., an orthorhombic phase (0≤x<0.03), orthorhombic–tetragonal phases (x=0.03), orthorhombic–tetragonal and rhombohedral–orthorhombic (O–T and R–O) phase existence (0.03<x≤0.05), a rhombohedral phase (0.05<x≤0.07). The ceramics with O–T and R–O have a better piezoelectric behavior as compared with other phases because of more polarization states, enhanced εr and Pr, and a dense microstructure. Moreover, piezoelectric properties could be further optimized by modifying their sintering and poling temperatures. As a result, the construction of O–T and R–O phase coexistence benefits the improvement of piezoelectric properties in KNN-based ceramics. 相似文献