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121.
Ahmed Al‐Busaidi Mushtaque Ahmed 《The International journal of environmental studies》2013,70(1):25-29
A stripping technique has been used to cencentrate selected hydrocarbons present in water samples at the parts per billion level for analysis by gas chromatography. The chromatograms of hydrocarbons thus stripped from several different water samples show similarities. Washing out of atmospheric pollutants by rainfall is postulated as an explanation of these results. This hypothesis is supported by a comparison of the data with those for trace atmospheric analysis. The comparison shows that the same compounds are present in similar relative amounts both in water samples and the atmosphere. After a period of rain the atmospheric concentrations decrease whilst the water bound concentrations increase. 相似文献
122.
Sagheer Gul Mazhar Mehmood Bakhtiar Muhammad Saira Jabeen 《Polymer-Plastics Technology and Engineering》2016,55(17):1842-1862
An efficient method to obtain better properties of epoxy-based nanocomposites is to introduce thermoplastic polymer such as polyamide into thermosetting resin. Combined effect of both polymers provides extra-bonding sites for nanofiller dispersion. This review mainly covers inorganic nanofiller dispersed epoxy/polyamide nanocomposite and their applications. To understand interaction between thermoset epoxy and thermoplastic polyamide, knowledge of structure, synthesis, and categorization is worth important. Addition of inorganic nanofiller such as layered silicate and metal oxide results in enhanced thermomechanical, physiochemical, and anticorrosive properties of resultant nanocomposite. These nanocomposites have applications as protective coatings, adhesives, insulators in electrical devices, and in aerospace industries. 相似文献
123.
Sagheer Gul Bakhtiar Muhammad Saira Jabeen 《Polymer-Plastics Technology and Engineering》2016,55(13):1393-1415
This review covers almost all known categories of compounds used for nanoclay surface modification with special emphasis on organic modification of layered silicate montmorillonite. Commonly used organic modifiers include quaternary ammonium ions, quaternary phosphonium ions, and amino acids. Dispersion of organomodified nanoclays in epoxy is particularly focused upon in this article. Epoxy-based materials are used as convenient matrices for montmorillonite dispersion since years due to superior properties of resulting polymeric nanocomposites, such as mechanical strength, electrical conductivity, flammability, and thermal stability. Owing to their high performance epoxy nanocomposites have endless applications in aerospace, automotives, construction, electrical, adhesives, and coating industries. 相似文献
124.
Microencapsulation of red and white thyme oil in poly(lactic‐co‐glycolic) acid: Assessment of encapsulation efficiency and antimicrobial capacity of the produced microcapsules 下载免费PDF全文
125.
Influence of plasticizers and cryogenic grinding on the high‐cooling‐rate solidification behavior of PBT/PET blends 下载免费PDF全文
Anesh Manjaly Poulose Stefano Piccarolo Domenico Carbone Saeed M. Al‐Zahrani 《应用聚合物科学杂志》2016,133(10)
Two structurally different plasticizers (cyclic and linear) and the effect of cryogenic grinding on the solidification behavior at high cooling rates by a continuous cooling transformation approach of poly(butylene terephthalate)/poly(ethylene terephthalate), PBT/PET, blends are described. The solidification curve (density versus cooling rate) is confirmed as an effective tool to compare the differences in crystallization behavior under conditions mimicking processing. In comparison to the bulky cyclic plasticizer, the linear oligomeric one was found to have a more pronounced influence on the crystallization behavior. A 60/40 by weight PBT/PET blend shows a drop‐off of density at ~50 K/s. In the plasticized sample, the long‐range crystalline order appears up to a cooling rate of ~250K/s, making the blend comparable to pure PBT. Grinding the components before blending further improves crystallizability and synergy to the addition of the plasticizer. The results suggest the important role of local chain mobility in the solidification behavior at high cooling rates. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43083. 相似文献
126.
Freestanding fiber mats of zeolitic imidazolate framework 7 via one‐step,scalable electrospinning 下载免费PDF全文
Seongpil An Ji Sun Lee Bhavana N. Joshi Hong Seok Jo Kirill Titov Jong‐San Chang Chul‐Ho Jun Salem S. Al‐Deyab Young Kyu Hwang Jin‐Chong Tan Sam S. Yoon 《应用聚合物科学杂志》2016,133(32)
We demonstrated the fabrication of freestanding zeolitic imidazolate framework 7 (ZIF‐7) nanofiber (NF) mats by means of one‐step, scalable electrospinning. The formation of ZIF‐7 nanoparticles embedded in polymer fibers was unambiguously pinpointed via X‐ray diffraction, transmission electron microscopy, and adsorption studies. The NF mats exhibited excellent characteristics, with an average diameter of 245 nm, in the adsorption and desorption of carbon dioxide (CO2); this makes them attractive candidates for gas separation and other selective filtration applications. This excellent property of the ZIF‐7 mats was explained by the gate‐opening phenomenon of ZIF‐7, which yielded a stepwise increase in the overall CO2 uptake capacity. The mechanical strength of the NF mats was also obtained via large‐strain uniaxial tensile deformation, which enabled preliminary assessment of the mat's suitability for textiles and membranes in targeting separation and filtration applications with large‐area permeability. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43788. 相似文献
127.
Mustafa S. Nasser Mohammed J. Al-Marri Abdelbaki Benamor Sagheer A. Onaizi Majeda Khraisheh Mohammed A. Saad 《Korean Journal of Chemical Engineering》2016,33(2):448-455
The effects of the surface charge type and density C496, C492 and A130LMW polyacrylamides (PAMs) on the rheological behavior of real industrial papermaking suspensions were quantitatively related to the degree of flocculation for the same industrial papermaking suspensions. The floc sizes were larger but less dense when anionic PAM was used, and this due to the repulsive forces between the anionic PAM and colloidal particles, leading to the development of open structure flocs of less density. On the other hand, rheological measurements showed that the papermaking suspension is thixotropic with a measurable yield stress. The results showed that the magnitude of the critical stress, τ c , complex viscosity, η*, elastic modulus, G′, and viscous modulus, G″, depend on the number of interactions between the PAM chains and particle surface and the strength of those interactions. Cationic PAM showed higher values of η*, G′, G″ and τ c compared to anionic PAM. This behavior is in good agreement with Bingham yield stress, τ B , adsorption and effective floc density results. Similar to oscillatory measurements, creep measurements also showed that the deformation was much lower for the cationic PAM based suspensions than for the anionic PAM based suspensions. Furthermore, the results revealed that increasing the cationic PAM surface charge decreases the floc size but increases the adsorption rate, elasticity and effective floc density proposing differences in the floc structures, which are not revealed clearly in the Bingham yield stress measurements. 相似文献
128.
Musarat Amina Touseef Amna Mallick Shamshi Hassan Nawal Musayeib Al Musayeib Salem Slayyem Salem Al-Deyab Myung-Seob Khil 《Korean Journal of Chemical Engineering》2016,33(11):3169-3174
Pure water is the fundamental requisite for human life. The water has been recycled naturally but not in an adequate amount for consumption. Nanotechnology with extraordinary applications provides competent ways for the decontamination of contaminated water. In the present study MnWO4 nanoflowers endorsed with inherent antibacterial activity were successfully synthesized by facile hydrothermal approach. XRD, SEM, EDX spectroscopy and UVDRS were used to characterize the as-synthesized nanoflowers. Gram negative Escherichia coli ATCC 52922 bacterium was used as model organism to test antibacterial activity of as-synthesized MnWO4 nanoflowers. This study was conducted to optimize minimum concentration of MnWO4 nanoflowers and maximum contact time required to achieve complete inactivation of bacteria present in contaminated water. Minimum inhibitory concentration (MIC) of MnWO4 nanoflowers was found to be 10 μg/ml. The assessment and interpretation of bacterial viability was done using dual fluorescent staining. The synthesized 3D-nanoflowers were found as potent bactericides. Thus, MnWO4 nanoflowers emerged to be very good future material for disinfection of biological pollutants present in the contaminated water reservoirs and as an anti-biofouling agent. 相似文献
129.
<正>本住宅建于18世纪末,乍一看会让人觉得这是座一无是处的破房子。住宅仅有一层,砖地已经破败不堪,黑暗和寒冷充斥着整个房子,木质的屋顶结构也已经腐坏。只有土墙看上去还有翻新的可能,毕竟它们好像并没有那么糟糕。住宅的业主并不强调私密性:厨房、起居室、餐厅和卫生间都是公用的。这样设计的原因是业主经常在这里接待来访者和朋友。在这所房子里,私人空间被压缩成每位家庭成员的床位。 相似文献
130.
Fibre Chemistry - The paper investigates factors affecting the production of high-count fabrics using projectile weaving machines, as well as providing recommendations for improving the design of... 相似文献