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1.
对新型细旦浸胶帘子布进行试生产。在试生产过程中,针对其高经密、高总经根数的特点,增加了整经工序,并在此基础上,对整经工艺、织造工艺及浸胶工艺进行探索,确定了该新型细旦浸胶帘子布的工艺参数。从试验结果来看,此次试生产达到了预期目标,并初步验证了在帘子布织造行业使用整经工序来开发生产高端细旦产品的优势,为开发高经密、高总经根数产品积累了初步经验。 相似文献
2.
Properties of polyamide 6,10/poly(vinyl alcohol) blends and impact on oxygen barrier performance 下载免费PDF全文
Jia‐wei Wu Ya‐qiong Huang Hong‐bo Li James Runt Jen‐taut Yeh 《Polymer International》2018,67(4):453-462
The oxygen transmission rate, average volume of free‐volume cavities (Vf) and fractional free volume (Fv) of polyamide 6,10 (PA610)/poly(vinyl alcohol) (PVA) (i.e. PA610xPVA05y, PA610xPVA08y and PA610xPVA14y) blend films reduced to minimum values when their PVA contents reached corresponding optimal values. Oxygen transmission rate, Vf and Fv values obtained for optimal PA610xPVAzy blown films were reduced considerably with decreasing PVA degrees of polymerization. The oxygen transmission rate of the optimal bio‐based PA61080PVA0520 blown film was only 2.4 cm3 (m2·day·atm)?1, which is about the same as that of the most often used high‐barrier polymer, ethylene–vinyl alcohol copolymer. Experimental findings from dynamic mechanical analysis, differential scanning calorimetry, wide‐angle X‐ray diffraction and Fourier transform infrared spectroscopy of the PA610xPVAzy blends indicate that PA610 and PVA in the blends are miscible to some extent at the molecular level when the PVA contents are less than or equal to the corresponding optimal values. The considerably enhanced oxygen barrier properties of the PA610xPVAzy blend films with optimized compositions are attributed to the significantly reduced local free‐volume characteristics. © 2017 Society of Chemical Industry 相似文献
3.
In order to improve the toughness, wear resistance, and combustion properties of the monomer casting nylon (MC nylon) materials, the polydimethylsiloxane (PDMS) segment is bonded to the nylon molecular chain by copolymerization. PDMS/MC nylon copolymers are prepared via in situ anionic polymerization with macro-activator based on PDMS terminated with hexamethylene diisocyanate. The effects of different macro-activator content on the mechanical properties, water absorption, thermal stability, friction and wear properties, and combustion properties of the copolymers are characterized. The results show that the impact strength of the copolymer improves significantly (optimally increases by 2.6 times) and the water absorption rate decreases with the increase of PDMS content. The introduction of the silicon–oxygen structure reduces the peak heat release rate of copolymer materials (optimally decreases about 28.7%), while it promotes the decomposition of the system, resulting in a slight decrease in the thermal stability of the materials. Adding 5 wt % PDMS can decrease the wear loss of MC nylon from 6.2 mg of pure nylon to 1.6 mg. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48753. 相似文献
4.
Understanding interactions between functionalized gold nanoparticles (NPs) and lipid bilayers is essential for biomedical applications. Experiments have shown that NPs that are stable in solution can assemble into clusters when adsorbed to a lipid bilayer, suggesting that bilayer-mediated interactions facilitate assembly. In this work, we use coarse-grained molecular dynamics simulations to study bilayer-mediated interactions between NPs adsorbed to single- and multicomponent lipid bilayers. We perform unbiased simulations and umbrella sampling calculations using an implicit solvent force field to determine the thermodynamic contributions to assembly. We show that bilayer-mediated interactions drive the assembly of NPs into linear aggregates on liquid-disordered bilayers, which we attribute to a reduction in bilayer curvature. Similar bilayer-mediated interactions induce the alignment of NP clusters with phase boundaries in phase-separated bilayers. Together, these simulation results provide new physical insight into the balance of forces that dictate the assembly of charged NPs at multicomponent lipid bilayer interfaces. 相似文献
5.
Near- and short-wave IR emission spectra of printed cotton/nylon blend fabrics coated with inorganic compounds in order to tune their diffuse reflectance behavior to the ones with woodland and desert backgrounds are investigated. In this regard, cotton/nylon blend fabrics printed with a four-color digital pattern were used as the substrate, and different concentrations of zirconium and cerium dioxide (ZrO2 and CeO2) with and without citric acid as a cross-linker were loaded on these fabrics using the pad-dry-cure method. The diffuse reflectance of the coated fabrics with various concentrations of nanoparticles and a cross-linker was first measured by near-infrared (NIR) diffuse reflectance spectroscopy (DRS). Then, fabrics with an optimum concentration of nanoparticles and appropriate reflectivity profiles similar to woodland and desert were investigated by field emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), washing, and rubbing fastness properties. In general, NIR and short-wave infrared (SWIR) reflectance of fabrics coated with ZrO2 and CeO2 nanoparticles in range of 1% to 1.5% (w/v [%]) was suitable for matching with different environments. According to the findings obtained from the durability test, it was concluded that the washing fastness of the treated fabrics with CeO2 nanoparticles was excellent in both environments. FE-SEM images of the treated fabrics containing ZrO2 and CeO2 indicated that the presence of nanoparticles on the surface of fabrics in woodland patterns was greater than the desert ones. However, the coated fabrics with CeO2 and citric acid in the woodland pattern have shown better dispersion with a mean particle size of 30 to 60 nm. 相似文献
6.
MC68 4 5是Motorola生产的一种 4 0引脚的双列直插式可编程器件 ,阐述了一种用MC684 5制作的工业控制机图形显示模板的电路原理 ,其设计思路对从事这方面的开发和应用都会有所启发。 相似文献
7.
提出了一种基于MC145162数字锁相环在频率发射电路中的设计与应用,概述了锁相环原理以及给出了系统平台的构架和发射电路的硬件框图,描述了采用MC145162数字锁相环与AT89S52芯片作为系统的硬件平台,通过SPI接口对其MC145162数字锁相环进行软件上的设置,得到所需要的频率,构建一个可靠、经济的无线数据传输平台,将此平台运用于井下无线设备的工控上. 相似文献
8.
根据在煤矿井下工作的660V/1 140 V交流电动机起动电流大,对电网及电机造成冲击的缺点,设计了一种新型的矿用隔爆型软起动器。文章着重介绍了以87C196MC单片机为控制核心的控制系统硬件电路及软件设计。针对隔爆箱体积小、强弱电相互干扰严重、功率元件散热性差的缺点,相应的设计了精简的硬件电路、采用了硬件与软件的抗干扰措施。该软起动器具有软起动、软停车、漏电保护等近10种保护功能,充分地保证了交流电动机在煤矿井下的正常使用。 相似文献
9.
Sub-micrometer particulate air pollution and cardiovascular mortality in Beijing, China 总被引:1,自引:0,他引:1
Breitner S Liu L Cyrys J Brüske I Franck U Schlink U Leitte AM Herbarth O Wiedensohler A Wehner B Hu M Pan XC Wichmann HE Peters A 《The Science of the total environment》2011,409(24):5196-5204
Background
While the link between particulate matter and cardiovascular mortality is well established, it is not fully investigated and understood which properties of the aerosol might be responsible for the health effects, especially in polluted mega-city areas.Objectives
Our goal was to explore the association between daily cardiovascular mortality and different particle metrics in the sub-micrometer range in Beijing, China.Methods
We obtained daily counts of cause-specific cardiovascular deaths in the Beijing urban area for the period March 2004 to August 2005. Concurrently, continuous measurements of particle number size distributions were performed. Particle number concentrations (NC) between 0.003 μm and 0.8 μm were converted to particle mass and surface area concentrations assuming spherical particles. Semi-parametric Poisson regression models adjusting for trend, seasonality, day of the week, and meteorology were used to estimate immediate, delayed and cumulative particle effects. Additionally, effect modification by air mass origin was investigated.Results
We observed associations between daily cardiovascular mortality and particle NC for a 2-days delay. Moreover, nearly all particle metrics showed 2-days delayed associations with ischemic heart disease mortality. The strongest association was found for particle NC in the size range 0.03-0.1 μm (7.1% increase in daily mortality with a 95%-confidence interval of 2.9%-11.5%, per an increase of 6250 particles/cm3). Results for surface and mass concentrations with a lag of two days indicated effect modification by air mass origin, whereas effects of particle NC were not modified.Conclusions
Results show an elevated risk of cardiovascular mortality in Beijing from short-term exposure to particulate air pollution in the sub-micrometer range. Results also indicate that locally produced smaller particles and regionally transported particles may exhibit different effects in Beijing. 相似文献10.