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1.
指出了我国饲料添加剂品种少、产量低、技术水平低、创新少等问题,提出了发展氨基酸、药物添加剂、生物工程等一系列建议。  相似文献   
2.
Superhydrophobic and UV protective textiles are of growing interest from the last few decades. In this study, silica nanoparticles (SiO2) were synthesized by the sol-gel method. The synthesized silica nanoparticles were applied on nylon knitted fabric by pad-dry-cure technique. The silica nanoparticles coating on fabric was modified by in situ deposition of zinc oxide (ZnO) followed by hydrophobic modification using sodium stearate (SS). The fabrics were characterized by Fourier transform infrared spectroscopy, X ray diffractometry, and scanning electron microscopy. The hydrophobic properties of the fabric were assessed by water contact angle measurement and ultraviolet protection properties of fabric were assessed by Australian/New Zealand Standard (AS/NZS 4399:1996). Modified fabric showed superhydrophobicity with water contact angle of 151°. The fabric also showed excellent ultraviolet protection with ultraviolet protection factor of 279.68. The fabric exhibited retention of hydrophobic and UV protection properties up to 10 washing cycles.  相似文献   
3.
Polyester (PET) nanocomposite fibers were spun by adding master batches of linear low‐density polyethylene (LLDPE) loaded with Montmorillonite (MMT) nanoclay after compatibilizing the PET and LLDPE. The spun fibers showed increased thermal stability as well as flame retardancy, which increased progressively with the amount of nanoclay loaded into the fiber. There is slight decrease in tensile strength of the fiber accompanied by decrease in elongation % indicating addition of nanoclay makes the filaments stiffer. The onset of crystallization temperature occurred at higher temperature in case of composite fibers than on the neat PET fiber because of nucleating effect of nanoclay. The dyeability of the fibers was not affected and also had very little impact on the flame retardancy of the fiber. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers  相似文献   
4.
Synthetic polymers are based on the use of crude oil as their raw material. Oil spillage takes place during production, storage, transportation and usage at the water bodies and land surfaces. This may be due to tanker disasters, wars, operation failures, equipment breaking down, accidents and natural disasters. The spilled oil into land, river or ocean imposes a major threat to the environment and endangers the aquatic life. To overcome this problem, oil sorbents are commonly used for cleaning the oil spills. In this paper, coir fibre which was obtained as a waste from coconut fruit was functionalized to increase its hydrophobicity and oil sorption capacity. The product so formed was characterized by FT-IR, TGA and SEM which confirmed grafting of butyl acrylate monomer onto the coir fibres. The effects of time, temperature and monomer concentration on the grafting of coir fibre and oil absorption capacity have also been investigated. Results demonstrated that the modified coir fibre absorbed fair amount of crude oil and studies also indicate that a simple squeezing was sufficient to remove most of the oil sorbed by the fibres so that the sorbents can be reused several times for oil spill clean-up.  相似文献   
5.
Apparent diffusion coefficients of two disperse dyes for so-called easily dyeable/cationic-dyeable polyester (ED-CDPET) and cationic-dyeable polyester (CDPET) fibres of identical linear density and sulphonic acid group content have been calculated. It was found that the diffusion coefficients of dyes for ED-CDPET were far greater than those of dyes for CDPET. The dyeability at the boil without carrier, using disperse and cationic dyes on various ED-CDPET and CDPET fibres, has been studied. ED-CDPET was found to have higher dyeability at all levels of heat setting (irrespective of the dye used). The finest ED-CDPET fibres showed maximum dye uptake as a result of increased surface area. Heat setting in the taut condition reduced dye uptake.  相似文献   
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In recent years, social media have increased the resources that individuals and organizations are able to mobilize for the development of socially innovative practices. In this article, we engage with a naturally occurring development in a Trentinian neighbourhood to examine the cooperative interactions amongst members of a local community. The first author and local residents of the neighbourhood participated in online discussions, decision making, and physical activities that led to material changes in the area. The interventions are motivated by and based on the concept of Social Street that combines online interactions in a closed Facebook group with face-to-face meetings seeking to practically engage the collective in accomplishing certain immediate or ongoing needs. Over the course of two years, we studied this local instantiation of Social Street in Trento, Italy by way of an action-oriented (digital) ethnography. Through this work, we demonstrate how urban neighbourhoods might benefit from hybrid forms of community engagement that are enacted through a constant back and forth between online and face-to-face interactions. We further argue that the infrastructuring of local urban collectives should follow strategies that pay attention to the multiple issues in urban neighbourhoods and people’s attachments to them. Overall, the paper reflects upon the challenges and configurations of participation that this form of community-work entails.  相似文献   
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采用离子注入技术对射频磁控溅射制备的ZnO薄膜进行N掺杂,通过退火实现了ZnO薄膜的p型转变.利用X射线衍射(XRD)和Hall实验对样品热退火前后的性能进行了研究.实验数据表明,该掺杂方法能得到稳定的p型ZnO薄膜,其电学性能随热退火温度的升高和时间的延长而进一步改善,其中在950℃、7min退火条件时,载流子浓度为1.68E 16cm-3,电阻率为41.5Ω·cm.  相似文献   
10.
徐闻X3井是一口部署在北部湾盆地迈陈凹陷区块的多靶点定向井, 也是中石化首口超高温超深四靶点定向探井,该井二开井段长达2 667 m,为大尺寸长裸眼井眼;三开实钻裸眼段长1 540 m。该地区地温梯度高,井深5 974 m电测温度为211 ℃,高温影响MWD仪器使用性能,下部井段只能依靠多点投测,井身轨迹控制具有滞后性。为实现徐闻X3井井眼轨迹的有效控制,该井直井段采用塔式钻具组合,长达2 028 m的直井段最大井斜角仅为1.39°,定向井段采用1.5°的单弯螺杆定向,稳斜井段采用满眼、微增钻具组合钻进。该井4个靶点均顺利中靶,实钻井眼轨迹达到设计要求,完钻井深6 010 m,完钻水平位移达2 017.22 m。该井的顺利完钻为同类井的施工提供了经验。  相似文献   
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