Interfacially reinforced methylphenylsilicone resin composites by chemically grafting multiwall carbon nanotubes onto carbon fibers

Both silane and multiwall carbon nanotubes (CNTs) were grafted successfully onto carbon fibers (CFs) to enhance the interfacial strength of CFs reinforced methylphenylsilicone resin (MPSR) composites. The microstructure, interfacial properties, impact toughness and heat resistance of CFs before and after modification were investigated. Experimental results revealed that CNTs were grafted uniformly onto CFs using 3-aminopropyltriethoxysilane (APS) as the bridging agent. The wettability and surface energy of the obtained hybrid fiber (CF-APS-CNT) were increased obviously in comparison with those of the untreated-CF. The CF-APS-CNT composites showed simultaneously remarkable enhancement in interlaminar shear strength (ILSS) and impact toughness. Moreover, the interfacial reinforcing and toughening mechanisms were also discussed. In addition, Thermogravimetric analysis and thermal oxygen aging experiments indicated a remarkable improvement in the thermal stability and heat oxidation resistance of composites by the introduction of APS and CNTs. We believe the facile and effective method may provide a novel interface design strategy for developing multifunctional fibers.     

Protein hydrolysates from animal processing by-products as a source of bioactive molecules with interest in animal feeding: A review

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.     

Ca2+ enhances algal photolysis hydrogen production by improving the direct and indirect pathways

In this study, Ca²⁺ was applied to enhance the photolysis H₂ production of Chlamydomonas reinhardtii grown in pure culture or co-cultivated with bacterium. With addition of Ca²⁺, the chlorophyll and protein contents in algal cells were maintained at high levels and the reactive oxygen species (ROS) were scavenged to tolerable levels by activities of catalase (CAT) and superoxide dismutase (SOD). High chlorophyll and low ROS are benefit to protect the photosystem II (PS II) activity that responsible for the direct photolysis H₂ production. Moreover, addition of Ca²⁺ was able to promote the acetic acid assimilation as well as the starch synthesis. The starch degradation, in return, contributed to the H₂ production via the indirect photolysis pathway. Based on the improvements of direct and indirect photolysis pathways, the H₂ production of algae grown in co-cultivation adding with 5 mM Ca²⁺ reached a maximum value of 306 mL L⁻¹, which was 2.4 times higher than the production without Ca²⁺ addition. This study gives an efficient and easy strategy to improve the algal photolysis H₂ production, and gets an insight into the mechanisms of the improvement.     

平面压降梯度计算原则及其应用

超压作为油气运移的动力条件，其变化速率与油气运移方式存在一定的关系。为定量判识超压盆地中油气运移方式，建立了应用地层压降梯度分析的计算思路与方法，并以渤海湾盆地沾化凹陷渤南洼陷为例进行了应用和探讨。以实测压力与单井预测压力为基础，对油气主要运移层系进行了压力分布特征分析，结合超压成因机制分区、沉积相变以及断层发育特征，分别对压力均匀降低区、沉积相变非均匀降低区和断层分割非均匀降低区采用不同的压降梯度计算思路进行计算。渤南洼陷深洼带的压降梯度最高，其次为断阶带、陡坡带以及缓坡带，且垂向连通的断层附近压降梯度较高，定量地解释了在超压控制下油气运移方式的变化特征，从而有效判识油气优势富集的位置。      

溶解氧变化对阴极极化下10Ni5CrMo钢氢脆敏感性的影响

摘要：为研究溶解氧质量浓度对10Ni5CrMo钢在阴极极化条件下氢脆敏感性影响规律，对10Ni5CrMo钢进行了阴极极化下的电化学交流阻抗谱测试﹑并采用慢应变速率拉伸实验和断口分析方法研究了海水中溶解氧质量浓度变化和不同阴极极化下10Ni5CrMo钢的氢脆敏感性。结果表明：溶解氧质量浓度变化对10Ni5CrMo钢强度几乎没有影响；同一溶解氧质量浓度下，随极化电位负移，断裂时间、伸长率、断面收缩率明显降低，氢脆系数增加，氢脆敏感性显著提高，极化电位达到-1000mV时，氢脆系数已超过安全区允许的最高值25%，进入危险区；同一极化电位下，随着海水中溶解氧质量浓度减少，材料塑性变差，断裂时间、伸长率和断面收缩率不断降低，氢脆系数增加，氢脆敏感性提高。     

Clinical observations of the effect of orthokeratology in children with myopic anisometropia

PurposeTo evaluate the clinical effect of orthokeratology in controlling myopia and treating anisometropia among children with myopic anisometropia.MethodsA total of 108 myopic anisometropic children aged 8–16 years old who wore orthokeratology lenses in both eyes were enrolled in this study and followed up for over 1 year. The more severely myopic eye of each patient was assigned to the more myopic group (108 eyes), with a mean spherical equivalent refraction of −4.25 (−5.00, −3.38) D; the opposite eye of each patient was assigned to the less myopic group (108 eyes), with a refraction of −2.75 (−3.63, −1.88) D. This study observed and analyzed changes in ocular parameters after orthokeratology (Wilcoxon signed-rank test).ResultsIn children who wore orthokeratology lenses for approximately 1 year, the level of anisometropia significantly dropped from 1.38 (1.13, 1.75) D to 1.25 (1.13, 1.75) D (P = .005). The difference between the axial lengths of the two eyes significantly dropped from 0.54 (0.37, 0.74) mm to 0.46 (0.28, 0.67) mm (P< .0001).ConclusionsOrthokeratology seemed to be more effective at delaying the progression of myopia in the more myopic eyes than in the less myopic eyes of myopic anisometropic children. Orthokeratology lenses are suitable for anisometropic children, although the effectiveness of orthokeratology against anisometropia requires additional follow-up time for further observation and study.     

石化项目地下水保护措施有效性分析

石化产品在储运过程中若发生污染事故,污染物会通过包气带渗入到地下水中,对地下水质量产生影响。通过预测,制定科学的地下水防治措施,是防止项目对地下水环境造成影响的有效手段。以广东某石化建设项目为例,在查明水文地质条件的基础上,预测和评价项目运营期对地下水环境可能造成的影响,并针对这种影响提出相应的防渗技术措施且预测了防渗措施的有效性。预测结果表明:采取防渗措施后,污染源强对地下水的影响范围明显缩小,说明防渗措施能有效的防止污染物进入地下水,保护地下水资源。     

Highly sensitive C2H2 gas sensor based on Ag modified ZnO nanorods

The sliver (Ag) modified zinc oxide (ZnO) nanorods were successfully obtained with a simplified and environmentally friendly solvothermal method. Materials characterization indicated that the metallic Ag was located on the outside of ZnO nanorods after annealing. In comparison with ZnO nanorods, Ag modified ZnO (Ag–ZnO) nanorods exhibited a considerably enhanced response to C₂H₂. The response of the 3 at% Ag–ZnO based sensor operating at 175 °C is 539 (R_a/R_g), which is the highest value among all the sensors in detecting 100 ppm C₂H₂. The Ag–ZnO based sensors exhibited fast response speed, lower operation temperature and higher selectivity.     

Mechanical properties of graphene films enhanced by homo-telechelic functionalized polymer fillers via π–π stacking interactions

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.     

Grain size influence on the flexibility and luminous intensity of inorganic CaTiO3:Pr3+ crystal nanofibers

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.