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Synthesis, Characterization, and Utilization of a Novel Phosphorus/Nitrogen-Containing Flame Retardant

INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH 2015年第11期54卷 2974-2982页

作者： Jiang, Peng Gu, Xiaoyu Zhang, Sheng Wu, Shende Zhao, Qian Hu, Zhongwu Beijing Univ Chem Technol Minist Educ Key Lab Carbon Fiber & Funct Polymer Beijing 100029 Peoples R China Beijing Univ Chem Technol Fire Safety Mat Lab Coll Mat Sci & Engn Beijing 100029 Peoples R China

The novel phosphortis/nitrogen=zontainirig flame retardant hexa(phosphaphenarithrene aminophenoxyl)-cyclotriphosphatene (HPAPC), which contains Phosphaphenanthrene [9,10-dihydro-oxa-10,phosphaphenanthrene 10-oxide (DOPO)] and phosphazene (hekachlorocyclotriphosphazene) groups;was synthesized by the classic Atherton-Todd reaction, and its chemical structure was characterized by Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies. Poly(lactic acid) (PLA) composites containing HPAPC were prepared by melt blending, and their fire performance and thermal behaviors were investigated in terms of limiting oxygen index (LOT);vertical burning (UL-94), dine calorimeter tests, and thermogravimetric analysis :(TGA). The LOT value could reach up to 347%, and UL 94 Could pass V-0 for the KA composite containing only 5 wt HPAPC, TGA results showed that the char formation of PIA could be significantly improved by the presence of HPAPC. The evolved gas of the Composite was analyzed by FTIR-TGA and pyrolysis gas chromatography/mass spectrometry (Py GC/IVIS). The dispersion of fillers in PLA was observed by:back-scattered electron (BSE). The Chat morphology was Characterized by FTIR Spectroscopy and scanning electronic microscopy (SEM). It was suggested that the 'presence of HPAPC could release ammonia gas during combustion, which was beneficial to the formation of an intumescent Char structure.

关键词： fire performance Fillers Scanning Electron Microscope Char formation Thermogravimetry Melt blending programmable logic arrays Fire Retardants Fourier transform infrared spectroscopy Composites RICTOR gene chemical structure

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Knowledge-Enhanced Physical Layer Authentication for Mobile Devices

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IEEE TRANSACTIONS ON CONSUMER ELECTRONICS 2024年第4期70卷 7436-7448页

作者： Wang, Qi Liang, Wei Zhang, Jialin Wang, Ke Jiang, Xiaolin Chinese Acad Sci Shenyang Inst Automat State Key Lab Robot Shenyang Peoples R China Chinese Acad Sci Key Lab Networked Control Syst Shenyang 110016 Peoples R China Chinese Acad Sci Inst Robot & Intelligent Mfg Shenyang 110169 Peoples R China Univ Chinese Acad Sci Shenyang Inst Automat Beijing 100049 Peoples R China Chinese Acad Sci Inst Robot & Intelligent Mfg Shenyang 110169 Peoples R China Royal Inst Technol Dept Intelligent Syst S-11428 Stockholm Sweden

Channel state information (CSI)-based physical layer authentication (PLA) is considered to be a promising technology for wireless network security. However, in mobile scenarios, device mobility and environmental dynamics limit the reliability of PLA due to channel state instability and spatial location uncertainty. To improve authentication reliability, we propose a knowledge-enhanced PLA algorithm. This algorithm leverages prior knowledge of mobile devices and wireless channels to verify mobility patterns and extract stable features. Specifically, trajectory verification, exploiting the space-time constraints of the mobile device, is conducted before and after location prediction to assess the rationality of the mobile trajectory. Moreover, a three-scale feature model is proposed to extract stable features for precise location prediction, which models the stable characteristics of unstable mobile channels from different sensitivities to spatial variations. Evaluation results show that the proposed algorithm can achieve higher reliability than two state-of-the-art algorithms in three mobile scenarios.

关键词： programmable logic arrays Mobile handsets Authentication Trajectory Task analysis Feature extraction Wireless communication Channel state information mobile device physical layer authentication wireless network

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Preparation, Characterization, and Biodegradation of PS:PLA and PS:PLA:OMMT Nanocomposites Using Aspergillus niger

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POLYMER COMPOSITES 2014年第2期35卷 263-272页

作者： Shimpi, Navinchandra G. Borane, Mahesh Mishra, Satyendra North Maharashtra Univ Univ Inst Chem Technol Dept Nanosci & Technol Jalgaon 425001 MS India

Poly(lactic acid) (PLA) was synthesized using l-lactic acid by condensation polymerization. Polystyrene (PS) and surface modified montmorillonite (OMMT) was used for the preparation of PS:PLA composites and PS:PLA:OMMT nanocomposites. The composite materials prepared had varying amount of PLA (10-30%) and OMMT (0.5-5 phr). These composites were subjected to degradation in minimal medium using the fungi Aspergillus niger (A. niger) under controlled conditions. Scanning electron microscopy (SEM) showed the growth of microorganism on the polymer surface and fracture within the polymer matrix as a result of degradation. Fourier transform infra red spectroscopy (FTIR) was further used to determine the mechanism leading to biodegradation. It was found that the biodegradation of both PS:PLA and PS:PLA:OMMT took place mainly via break down and utilization of ester group, as can be seen from disappearance of absorption peak of ester group and simultaneous appearance of a typical IR absorption of microbial mass at 1450 cm(-1). The thermal stability of PS:PLA:OMMT nanocomposites was found to increase with increasing concentration of OMMT, as observed from thermo gravimetric analysis (TGA), while mechanical property was found to be decreased after degradation at 30% of PLA and 5 wt% of OMMT content. Change in extracellular protein content, biomass production and % degradation with respect to time (up to 28 days) were studied and correlated to evaluate the effectiveness of A. niger in biodegradation of the composites. POLYM. COMPOS., 35:263-272, 2014. (c) 2013 Society of Plastics Engineers

关键词： infrared absorption polymer surface absorption peak biodegradation programmable logic arrays Fourier transform infrared spectroscopy Composites L-Lactic Acid Scanning Electron Microscope Nanocomposites Microbes Aspergillus niger Mechanical properties Organo-modified montmorillonite

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Crystallization Behavior, Morphology, and Mechanical Properties of Poly(lactic acid)/Tributyl Citrate/Treated Calcium Carbonate Composites

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POLYMER COMPOSITES 2014年第8期35卷 1570-1582页

作者： Shi, Nan Dou, Qiang Nanjing Univ Technol Dept Polymer Sci Coll Mat Sci & Engn Nanjing 210009 Peoples R China

In this article, poly(lactic acid) (PLA) composites containing titanate coupling agent treated calcium carbonate (T-CaCO3) and tributyl citrate (TBC) were prepared via melt blending. The crystallization, morphology, mechanical properties, and nonisothermal cold crystallization kinetics of PLA composites were studied by means of differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD), polarized light microscopy (PLM), scanning electron microscopy (SEM), and mechanical tests, respectively. The results show that TBC promotes crystallization of PLA. Both T-CaCO3 and TBC significantly decrease the spherulitic size, but the crystal structure of PLA is not changed. A synergistic toughening effect is obtained by the combination of T-CaCO3 and TBC. The nonisothermal cold crystallization kinetics of PLA composites is well described by Mo's method. The activation energies (Delta E) of nonisothermal cold crystallization were calculated by Kissinger and Takhor methods, respectively. It is found that the addition of T-CaCO3 and TBC increases Delta E, but it also increases the cold crystallization rate. VC 2013 Society of Plastics Engineers

关键词： Composites programmable logic arrays Cold crystallization calcium carbonate Crystallization crystallization force TBC1D1 gene Scanning Electron Microscope titanate coupling agent crystal structure Mechanical properties

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Simultaneous determination of berberine and palmatine in human plasma and in urine by capillary electrophoresis combined with polypropylene hollow fiber liquid-liquid-liquid microextraction

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ANALYTICAL METHODS 2014年第19期6卷 7928-7934页

作者： Song, Tianhe Zhang, Kalin Yanbo Lao, Lixing Lee, Kai Fai Tang, Sydney Chi Wai Ng, Tzi Bun Sze, Stephen Cho Wing Univ Hong Kong Sch Chinese Med Hong Kong Hong Kong Peoples R China Univ Hong Kong Dept Obstetricians & Gynaecologists Hong Kong Hong Kong Peoples R China Univ Hong Kong Dept Med Hong Kong Hong Kong Peoples R China Chinese Univ Hong Kong Fac Med Sch Biomed Sci Shatin Hong Kong Peoples R China

A sensitive and precise method for determination of berberine hydrochloride (BEH) and palmatine (PAL) in human plasma and in urine simultaneously was developed using capillary electrophoresis (CE) combined with polypropylene hollow fiber liquid-liquid-liquid microextraction (PHF-LLLME). Because of the reports of human poisoning as a consequence of unregulated use of some drugs containing alkaloids, development of a rapid and precise assay for alkaloid measurement in the clinical setting is desirable. We report herein the development of a sensitive and precise assay for the measurement of alkaloids in the setting of a clinic. Ten participants (6 men and 4 women with a mean age of 26.3) who resided in a closed research unit participated in the detection of alkaloids. All of the volunteers were healthy. BEH and PAL were selected as model compounds to develop and evaluate the performance of the proposed method. Under the optimum conditions, the linear range was 20-1600 ng mL(-1) for BEH, and 50-1600 ng mL(-1) for PAL. The limits of quantification for BEH and PAL were found to be 8.7 and 11.3 ng mL(-1), respectively. The average extraction recoveries in urine ranged from 87.3 to 102.4% and in plasma ranged from 78.2 to 109.7%. The RSDs were less than 4.2 and 10.5, respectively. The proposed method greatly improves the extraction efficiency and simplifies the experimental procedure considerably, and can be used as an automatic process for quantitative determination of alkaloids in a clinical setting.

关键词： SHCBP1 gene Urine programmable logic arrays AUTOMATIC PROCESSING Polypropylenes alkaloids Hollow Fiber LRIT1 gene Capillary electrophoresis palmatine Berberine

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Effect of Elongational Flow and Polarity of Organomodified Clay on Morphology and Mechanical Properties of a PLA Based Nanobiocomposite

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INTERNATIONAL POLYMER PROCESSING 2016年第5期31卷 541-547页

作者： La Mantia, F. P. Ceraulo, M. Mistretta, M. C. Sutera, F. Ascione, L. Nasillo, G. Univ Palermo Dipartimento Ingn Civile Ambientale Aerospaziale Mat Viale Sci Ed 8 I-90128 Palermo Italy Univ Palermo CGA Palermo Italy

In biodegradable polymer world nanobiocomposites represent a new group of materials filled with inert nanoparticles that shows very interesting properties and the biodegradability of the matrix. In this work we have studied the effect of the polarity of the organomodified montmorillonite and of the elongational flow on the morphology and the rheological and mechanical properties of a new nanobiocomposite with a matrix of biodegradable PLA based blend. The elastic modulus enhances in presence of the nanofiller and this increase is larger and larger with the increment of the orientation. The tensile strength does not show any significant change at the same level of orientation. Moreover, a brittle-to-ductile transition is observed in the anisotropic sample and this effect is again more evident for the nanocomposite. The raise of the interlayer distance is higher for the more polar montmorillonite, even if the two nanocomposites show about the same final interlayer distance and morphology. Some exfoliation is also observed as a result of the application of the elongational flow.

关键词： programmable logic arrays Elastic Modulus montmorillonite Nanocomposites polarity based biodegradability Mechanical properties

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High impact poly(lactic acid)/poly(ethylene octene) blends prepared by reactive blending

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POLYMER ENGINEERING AND SCIENCE 2013年第2期53卷 389-396页

作者： Feng, Yulin Hu, Yuexin Yin, Jinghua Zhao, Guiyan Jiang, Wei Chinese Acad Sci Changchun Inst Appl Chem State Key Lab Polymer Phys & Chem Changchun 130022 Peoples R China Chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

Poly(ethylene octene) grafted with glycidyl methacrylate (POE-g-GMA) was prepared and used to toughen poly (lactic acid) (PLA) via reactive blending. It was found that the notched Izod impact strength of PLA/POE-g-GMA blends improved dramatically when the content of elastomer was higher than 10 wt%. Reactive compatibilization between PLA and POE-g-GMA were studied by Fourier transform infrared spectroscopy (FTIR) and Molau test, the results showed the end carboxyl groups of PLA reacted with the epoxide groups of POE-g-GMA during blending. This considerably improved the compatibilization, leading to better wetting of the dispersed phase by the PLA matrix and finer dispersed POE-g-GMA particles with narrow distribution. Moreover, the critical interparticle distance (Lc) of the dispersed domains for PLA/POE-g-GMA blends system at room temperature was also identified. POLYM. ENG. SCI., 2013. (c) 2012 Society of Plastics Engineers

关键词： Blending REACTIVE Epoxy Compounds programmable logic arrays Fourier transform infrared spectroscopy elastic bodies Blends IZOD-IMPACT STRENGTH

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Poly(1,3-butylene adipate) Plasticized Poly(lactic acid)/Carbon Black as Electrical Conductive Polymer Composites

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POLYMER COMPOSITES 2009年第11期30卷 1576-1584页

作者： Qiao Zhijun Zhang Xingxiang Wang Ning Fang Jianming Tianjin Polytech Univ Inst Funct Fibers Tianjin 300160 Peoples R China Tianjin Univ Sch Sci Dept Chem Tianjin 300072 Peoples R China

Poly(1,3-butylene adipate) (PBA) as the plasticizer for poly(lactic acid) (PLA) and carbon black (CB) as conductive filler, electrically conductive polymer composites (CPC) with different CB and PBA contents were prepared. Fourier transform infrared revealed that the interaction existed between PLA/PBA matrix and CB filler, and PBA could improve this interaction. The rheology showed that CB could obviously improve the apparent viscosity and decrease the fluidity of the composites, but just the reverse for PBA. PLA/PBA/CB composites exhibited the low electrical percolation thresholds of 0.516, 1.20, 2.46, and 2.74 vol% CB at 30, 20, 10, and 0 wt% PBA. The conductivity of the composite containing 3.98 vol% CB and 30 wt% PBA reached 1.67 S/cm. Scanning electron microscopy revealed that the addition of PBA facilitated the dispersion of PLA/CB composites. PBA could dramatically increase the elongation at break of plasticized PLA. But high-PBA content caused the lowering of tensile strength. With the increasing of CB contents, the enforcement effect on the plasticized PLA became more obvious. POLYM. COMPOS., 30:1576-1584, 2009. (c) 2008 Society of Plastics Engineers

关键词： Composites APPARENT VISCOSITY Fluidity programmable logic arrays Citizens Band Radio private beauty adviser Plasticizers Elongation at break

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A 20 BIT LOGARITHMIC NUMBER SYSTEM PROCESSOR

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IEEE TRANSACTIONS ON COMPUTERS 1988年第2期37卷 190-200页

作者： TAYLOR, FJ GILL, R JOSEPH, J RADKE, J HONEYWELL INC CTR SYST & RESMINNEAPOLISMN 55440

The architecture and performance of a 20-bit arithmetic processor based on the logarithmic number system (LNS) is described. The processor performed LNS multiplication and division rapidly and with a low hardware complexity. Addition and subtraction in the LNS require the support of a table lookup unit. A scheme is proposed to minimize this complexity using a partitioned memory (ROM) and a PLA (programmable logic array). For performance evaluation, the target technology is integrated Schottky logic. The processor is shown to compare well with, if not to outperform, existing floating point (FLP) processors of equivalent range and precision. The speed-power-product ratio of an equivalent FLP processor, compared with that of the LNS processor, is reported to be 20 to 1 in the case of the square and square-root operation and 1 to 1 in the case of addition and subtraction. For multiplication and division, this ratio is about 5 to 1

关键词： Performance Evaluation Building construction ARCHITECTURE Schottky counting system Subtraction Logarithmic Multiplication and division programmable logic arrays Addition & subtraction fault-location problem PROCESSOR

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TiO₂/polystyrene core-shell nanoparticles as fillers for LLDPE/PLA blend: development, and morphological, thermal and mechanical properties

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POLYMER BULLETIN 2016年第11期73卷 3049-3063页

作者： Shimpi, Navinchandra G. Borane, Mahesh Mishra, Satyendra Univ Mumbai Dept Chem Bombay 400098 Maharashtra India North Maharashtra Univ Univ Inst Chem Technol Jalgaon 425001 Maharashtra India

Titanium dioxide/polystyrene (TiO2/PS) core-shell nanoparticles (CSNPs) reinforced linear low density polyethylene/poly (lactic acid) (LLDPE/PLA) blends were developed by means of compounding and injection moulding. TiO2/PS CSNPs were prepared by ultrasound-assisted method while PLA was prepared by polycondensation of l-lactic acid, and were added to commercial grade LLDPE. The morphological analysis, carried out by electron microscopy, revealed significant phase separation in LLDPE/PLA blends but showed improved compatibility in LLDPE/PLA (TiO2/PS) nanocomposites. The thermal behaviour of the nanocomposites, as observed from thermogravimetric analysis (TGA), was also improved as compared to its blend counterparts. The incorporation of TiO2/PS CSNPs also resulted in better mechanical properties. With the addition of 1 phr TiO2/PS CSNPs, the tensile strength and elongation of LLDPE/PLA/(TiO2/PS) nanocomposites increased significantly. The results demonstrate the effect of TiO2/PS CSNPs in providing better interfacial adhesion between LLDPE and PLA which led to significant improvement in the mechanical strength of the nanocomposites by allowing effective load transfer in the nanocomposites system. [GRAPHICS] .

关键词： Phase separation programmable logic arrays MECHANICAL STRENGTH Fillers L-Lactic Acid Nanocomposites Thermogravimetry Mechanical properties CONDENSATION POLYMERISATION Payload Linear low density polyethylenes Blends Thermal

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