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1.
A self-nanoemulsifying drug delivery system (SNEDDS) was developed to enhance the absorption of heparin after oral administration, in which heparin was compounded with phospholipids to achieve better fat solubility in the form of heparin-phospholipid (HEP-Pc) complex. HEP-Pc complex was prepared using the solvent evaporation method, which increased the solubility of heparin in n-octanol. The successful preparation of HEP-Pc complex was confirmed by differential scanning calorimetry (DSC), Fourier-transform infrared (FT-IR) spectroscopy, NMR, and SEM. A heparin lipid microemulsion (HEP-LM) was prepared by high-pressure homogenization and characterized. HEP-LM can enhance the absorption of heparin after oral administration, significantly prolong activated partial thromboplastin time (APTT) and thrombin time (TT) in mice, and reduce fibrinogen (FIB) content. All these outcomes indicate that HEP-LM has great potential as an oral heparin formulation.  相似文献   
2.
Most researches on graphene/polymer composites are focusing on improving the mechanical and electrical properties of polymers at low graphene content instead of paying attention to constructing graphene’s macroscopic structures. In current study the homo-telechelic functionalized polyethylene glycols (FPEGs) were tailored with π-orbital-rich groups (namely phenyl, pyrene and di-pyrene) via esterification reactions, which enhanced the interaction between polyethylene glycol (PEG) molecules and chemical reduced graphene oxide (RGO) sheets. The π–π stacking interactions between graphene sheets and π-orbital-rich groups endowed the composite films with enhanced tensile strength and tunable electrical conductivity. The formation of graphene network structure mediated by the FPEGs fillers via π–π stacking non-covalent interactions should account for the experimental results. The experimental investigations were also complemented with theoretical calculation using a density functional theory. Atomic force microscope (AFM), scanning electron microscope (SEM), X-ray diffraction (XRD), nuclear magnetic resonance (NMR), thermal gravimetric analysis (TGA), UV–vis and fluorescence spectroscopy were used to monitor the step-wise preparation of graphene composite films.  相似文献   
3.
《Ceramics International》2021,47(22):31329-31336
Traditional inorganic materials exhibit rigidity owing to the lack of polymer chains in polymer materials or atom slipping in metals. However, nanometerization has been recently proposed for the conversion of inorganic oxide materials into flexible materials. Herein, the flexible inorganic luminescent material, CaTiO3:0.2%Pr3+, was synthesized through electrospinning, and the macroscopic flexibility of pure inorganic CaTiO3:0.2%Pr3+ was achieved. The flexible membrane was characterized via X-ray diffraction, thermogravimetry, scanning electron microscopy (SEM), and photoluminescence analyses. The grain size was analyzed at various calcination temperatures via SEM, and the results suggested that the increase in the calcination temperature resulted in the growth of crystal grains. Studies have reported that the growth of crystal grains is beneficial for improving the luminescence performance; however, to obtain better flexibility, smaller crystal grains are required. This study provides an important reference for the design of flexible inorganic materials.  相似文献   
4.
Industrial processing of livestock, poultry and fish produces a large amount of waste in a solid or liquid form that can either be destroyed or be used to make compost, biogas or other low-added value products. However, the by-products from animal processing industries have a potential for conversion into useful products of higher value, such as protein hydrolysates, with interesting applications in animal feed. Low amounts of animal protein hydrolysates included in aqua-feeds may enhance growth rate and feed conversion of farmed fish and crustacean. Animal protein hydrolysates may also be incorporated in diets to enhance the nonspecific immunity of fish. As well, these hydrolysates can be used as a good source of amino acids for newly weaned animals. Protein hydrolysates from animal by-products including antimicrobials, antioxidants, opioid-like and/or other interesting bioactive molecules have promising and interesting applications on companion and production animals. By-products from animal processing industries are therefore a promising source of bioactive peptides of considerable interest for animal care, always within the framework of the existing legislation. Possible drawbacks and future trends of the use of animal by-products and/or production of protein hydrolysates from those materials are also discussed.  相似文献   
5.
The feasibility of microbial hydrogen consumption to mitigate the hydrogen embrittlement (HE) under different cathodic potentials was evaluated using the Devanathan-Stachurski electrochemical test and the hydrogen permeation efficiency η. The hydrogen permeation efficiency η in the presence of strain GA-1 was lower than that in sterile medium. The cathodic potential inhibited the adherence of strain GA-1 to AISI 4135 steel surface, thereby reducing the hydrogen consumption of strain GA-1. The adherent GA-1 cells were capable of consuming ‘cathodic hydrogen’ and reducing the proportions of absorbed hydrogen, indicating that it is theoretically possible to control HE by hydrogen-consuming microbes.  相似文献   
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7.
由于不同环境条件下,不同化探测试指标受到不同的因素干扰,所以不同介质样品的应用条件存在一定的差异。针对不同介质样品特点,分别采集海底沉积物、底部海水和低空大气3种介质样品,并采用在海底沉积物柱状样不同深度部位取样的立体取样方法,通过多指标综合分析,对不同介质和深度样品的多项化探指标互相进行了验证和补充,可以抑制干扰因素的影响,为油气资源远景评价提供依据。运用该方法在北黄海盆地油气勘查中进行初步尝试,并据此划分了三级化探异常区,提出了有利的含油气远景区,均与已知油气区和区域地质分析的结果相符合,取得了很好的效果。   相似文献   
8.
The ennoblement of corrosion potential (Ecorr) of passive metal immersed in seawater was investigated with electrochemical technology and epifluorescence microscopy. The in situ observation showed that the bacteria number increased on the metal surface according to an exponential law which was in the same way with the ennoblement of Ecorr. At the same time, the anodic polarization current of high‐Mo stainless steel decreased in the initial days. According to the mix‐potential theory and the characteristics of polarization curves of high‐Mo steel in natural seawater, the ennoblement of corrosion potential may be induced by the decrease of the passive current density.  相似文献   
9.
基于故障树与灰关联分析的鱼雷故障诊断   总被引:2,自引:0,他引:2  
孟范栋  李斌 《鱼雷技术》2006,14(4):56-58
将灰色关联度与故障树联合运用于鱼雷故障诊断,为鱼雷的故障诊断提供了一种新途径。在鱼雷动力系统故障树诊断模式识别中,运用灰色系统理论中的灰关联分析,通过进行关联度计算及排序,对各种故障模式发生的可能性大小作出了判断,从而为处理故障的轻重缓急、控制故障的发生以及改进系统的可靠性提供了理论依据。实例诊断表明,这种方法是有效可行的,并且诊断结果可靠。  相似文献   
10.
本文将条码扫描器应用于特种冰箱的制造中,建立了一种新型全自动集存库系统,重点分析了本系统的工作原理和硬件配置,及PLC的程序设计和触摸屏组态软件设计。  相似文献   
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