Turmeric nanofiber-encapsulated natural product formulation act as a phytogenic feed additive—A study in broilers on growth performance,biochemical indices of blood,and E. coli in cecum

A phytogenic feed additive (PFA) formulation was prepared with bioactive molecules—curcuminoids, gingerol, and carvacrol by encapsulating in nanofiber isolated from turmeric spent (turmeric nanofiber, TNF). This formulation was completely characterized by scanning electron microscope, ultra performance liquid chromatography, and gas chromatography and evaluated for its efficacy. PFA-encapsulated TNF (PFA@TNF) considerably increased mean body weight, decreased cholesterol level, mortality rate, and reduced Escherichia coli content of broilers than antibiotic growth promoter (AGP). The depth of crypts in the ileum of broilers was considerably reduced by the inclusion of PFA@TNF in diets compared with the AGP.     

Isotactic polypropylene–vapor grown carbon nanofibers composites: Electrical properties

Nanocomposites have been obtained by dispersing various amounts of vapor grown carbon nanofibers within isotactic polypropylene. Thermal investigations done by differential scanning calorimetry and dynamic mechanical analysis revealed the effect of the vapor grown carbon nanofibers on the melting, crystallization, α, and β relaxations. Direct current electrical features of these nanocomposites have been investigated and related to the thermal features of these nanocomposites. The effect of the loading with carbon nanofibers on the electrical properties of these nanocomposites is discussed within the percolation theory. The percolation threshold was estimated at about 5.5% wt carbon nanofibers. The temperature dependence of the direct current conductivity is analyzed in detail and it is concluded that the electronic hopping is the dominant transport mechanism. A transition from one‐dimensional hopping towards a three‐dimensional hopping was noticed as the concentration of carbon nanofibers was increased from 10% wt to 20% wt carbon nanofiber. The possibility of a differential negative resistivity is suggested. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45297.     

Direct Deposit of Fiber Reinforced Energetic NanoComposites

The ideal situation of assembling an energetic nanoparticles‐polymer matrix is obtaining materials with high particle loading while still maintaining mechanical integrity. In this paper, we introduced a direct deposition approach to create a reactive polymer fiber reinforced composite with aluminum (Al‐NPs) and copper oxide nanoparticles (CuO‐NPs) in a polyvinylidene fluoride (PVDF) reactive binder. Even with up to 70 wt % thermite, these films still maintain a uniform morphology and considerable flexibility. With the same overall material composition, both the reactive and mechanical properties of fiber reinforced films shown marked improvement over the corresponding non‐nanofiber films. The combustion propagation velocity of fiber reinforced films is up to 1.8 times faster than the corresponding non‐nanofiber films. For the mechanical properties, the films with 110 nm diameter fibers were 2.3, 23 and 5.8 times superior in tensile strength, strain and toughness respectively, as compared to films with the same mass loading but with no fibers. The results suggest deploying a fiber reinforced structure enables fabrication of nanocomposite with high loadings of energetic materials. These result imply that a 3‐D printing approach may demonstrate significant advantages in developing advanced propulsion systems.     

ZnO-TiO2纳米纤维的制备及亚甲基蓝的太阳光催化降解

以钛酸四丁酯〔Ti(OC4H9)4〕、硝酸锌和聚乙烯吡咯烷酮(PVP)为原料,采用溶胶-凝胶法和静电纺丝法制备无机有机复合的PVP/ZnO-TiO2纤维,高温焙烧制得直径100～200 nm的ZnO-TiO2纳米纤维。通过差动-热重(DSC-TGA)、傅里叶变换红外光谱(FTIR)、扫描电镜(SEM)等进行了表征,并测定了其对亚甲基蓝溶液的太阳光催化性能。结果表明,w(ZnO)=3%时,ZnO-TiO2纳米纤维对亚甲基蓝催化活性最高,太阳光照射6 h后降解率达99.4%,重复使用8次降解率仍然在95%以上。     

原位热溶剂法制备ZnO纳米晶/PU复合纳米纤维及其吸附性能研究

通过静电纺丝法制备了直径为(320±51)nm的前驱体醋酸锌/聚氨酯(Zn(OAc)2/PU)复合纳米纤维。将前驱体先后经过0.1 mol/L NaOH乙醇溶液和甘油浴热处理,得到ZnO纳米晶/PU复合纳米纤维。讨论了甘油浴温度和时间对纳米纤维结构和形貌的影响,研究了其吸附性能。实验结果表明,经过0.1 mol/L NaOH乙醇溶液处理后,前驱体纤维Zn(OAc)2/PU转变为ZnO/PU纤维且ZnO主要以低结晶和无定型态存在;再经过甘油浴处理后,低结晶和无定型态的ZnO转变为晶型完整的六方晶系纤锌矿结构,得到了ZnO纳米晶/PU复合纳米纤维,该纤维对有机染料分子罗丹明B有良好的吸附性能。     

聚合物纳米纤维技术与快速拓展的市场

介绍了聚合物纳米纤维技术与市场现状,重点论述了采用电喷法、强力纺、双组分熔融纺制备纳米纤维产品的技术特点,并对国内聚合物纳米纤维发展情况作了简要介绍。     

静电纺间位芳纶纳米纤维的制备工艺参数

通过静电纺丝方法,将氯化锂/N,N–二甲基乙酰胺(Li Cl/DMAc)溶解间位芳纶(PMIA)制备了PMIA纳米纤维,探索了溶液浓度、接收距离、纺丝电压及接收速度等工艺参数对纤维形貌及其直径分布的影响。通过扫描电子显微镜观察了PMIA纳米纤维形貌及应用Image-J软件测量统计了PMIA纤维直径。结果表明,溶液浓度为8%~10%、纺丝电压为16~18 k V、接收距离为15~20 cm,接收速度60~80 r/min的范围内,间位芳纶纳米纤维成型良好,直径分布范围为100~120 nm;PMIA纳米纤维直径随着溶液浓度的减小、静电电压的增加而减小,随着接收速度的增加纤维取向增加。     

Tunable microwave absorption properties of nickel-carbon nanofibers prepared by electrospinning

The nickel-carbon nanofibers (Ni-C NFs) were fabricated by the electrospinning of poly(vinyl alcohol) (PVA) and nickel acetate tetrahydrate (NiAc) solution precursor with succedent PVA pyrolyzation and calcination process. The microwave absorption performance and electromagnetic (EM) parameters of the NFs were researched over the frequency range of 2.0–18.0?GHz. Both the impedance matching and EM wave absorption properties of the Ni-C NFs were improved by changing the carbonization temperature. The effect of graphitization degree on reflection loss (RL) and the possible loss mechanisms were directly displayed in the comparative study of each sample. The optimal RL value of ??44.9?dB and an effective frequency bandwidth of 3.0?GHz under a thickness of 3.0?mm can be reached by a sample calcined at 650?°C. These lightweight Ni-C NFs composites can be promising candidates for EM wave absorbers due to the combination of multiple loss mechanisms, nano-size effect and good impedance matching between Ni nanoparticles and CNFs.     

Effect of fatigue loading on wicking properties of polyamide 66 nanofiber yarns

The wicking phenomenon is of prime importance with regards to biomedical applications of nanofiber yarns such as suture yarns and tissue scaffolds. In such applications, the yarns are usually subjected to cyclic tensile forces and biological tensile stresses. There is a lack of science behind the effect of fatigue on wicking properties of nanofiber yarns and this work aims at exploring this venue. Wicking properties of polyamide 66 nanofiber yarns are investigated by tracing the color change in the yarn structure resulting from pH changes during the capillary rise of distilled water. Results show that applying cyclic loading increases equilibrium wicking height in the Lucus–Washburn equation, which is attributed to changes in the overall pore structure in the cyclic loaded yarn. The likely causes of these changes are studied by scanning electron microscope, which reveals disentangled, more or less aligned and parallel nanofibers with a smaller radius in the nanofibrous structure. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47206.