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131.
Rohanda Anis Waris Abdul Kurniadi Rizal Bakhri Syaiful Pardi Pardi Haryanto Dwi 《核技术(英文版)》2020,31(11):1-11
Nuclear Science and Techniques - This study presents the RF design of a linear accelerator (linac) operated in single-bunch mode. The accelerator is powered by a compressed RF pulse produced from a... 相似文献
132.
Synthesis and characterization of (poly (N-vinyl formamide)—pregelled starch—graft copolymer 总被引:1,自引:0,他引:1
Khaled M. Mostafa Abdul Rahim Samarkandy Azza A. El-Sanabary 《Journal of Polymer Research》2010,17(6):789-800
Bromate / cyclohexanone redox system was investigated as a novel initiator for graft copolymerization of N-vinyl formamide
onto pregelled starch. A number of variables in the grafting reaction were investigated including N-vinyl formamide, cyclohexanone,
bromate ion, sulphuric acid and pregelled starch concentrations, material to liquor ratio along with polymerization time and
temperature. The graft copolymers were evaluated in terms of graft yield, graft reaction efficiency and homopolymer formation
(%). The optimum conditions for grafting of N-vinyl formamide onto pregelled starch are: N-vinyl formamide 50% based on weight
of substrate, cyclohexanone 15 mmol / l, bromate ion, 30 mmol / l, liquor ratio 10, pH 6, time 120 min., and temperature 40°C.
On the other hand, characterizations of the resultant copolymers with respect to swelling capacity, solubility %, metal ion
up-take and suitability as a sizing agent for cotton textiles were investigated. The results obtained reflect that, the resultant
copolymer shows better results for the aforementioned properties in comparison with that obtained from native pregelled starch
as a starting substrate. 相似文献
133.
Yew Joon Tam Morvarid Akhavan Rezaei Mohd Lila Mohd Azmi Abdul Rani Bahaman Sewn Cen Lo 《分离科学与技术》2016,51(5):816-829
Univariate screening on factors affecting the purification performance of recombinant hepatitis B surface antigen (HBsAg) on ion exchange chromatography (IEC) and size exclusion chromatography (SEC) and the establishment of a two-step purification strategy were performed. Amongst four IEC adsorbents examined, the use of Q Sepharose XL IEC adsorbent under optimized conditions together with optimized SEC purification was able to efficiently purify HBsAg. An established purification strategy comprising the two techniques further demonstrated adaptability for scale-up operations with a final total purification factor (PF) of 94.82 ± 16.20, HBsAg purity of 95.48% and recovery yield of 78.07%. 相似文献
134.
Michael H. Gordon Ibrahim Abdul Rahman 《Journal of the American Oil Chemists' Society》1991,68(8):574-576
The effect of various processing procedures on the composition and oxidative stability of coconut oil has been studied. The
crude oil is relatively stable but major reductions in oxidative stability occur during the bleaching of oil degummed with
phosphoric acid; during alkali refining; during the deodorization of oil degummed with citric acid and bleached; and during
the deodorization of oil processed with a combined phosphoric acid degumming and bleaching operation. The reasons for the
loss of oxidative stability during processing are discussed with reference to changes in the composition of the oil. Residual
traces of citric acid or phosphoric acid play an important role in stabilizing processed oils. The tocopherol content is also
important, although no additional stabilization of the oil occurs on adding levels of tocopherol above those present naturally
in the crude oil. A combined phosphoric acid degumming and bleaching process leads to smaller losses of tocopherols than sequential
treatments. 相似文献
135.
Nirmal Kumar Karan Samiran Mitra Georgina Rosair David J. Jenkins K. M. Abdul Malik 《Inorganic chemistry communications》2001,4(12)
A new alternating double aquo-bridged and single cyano-bridged polymeric complex {[Ba2(phen)4(H2O)6Fe(CN)6]·Cl·2(phen)·3H2O}n (1) (phen = 1,10-phenanthroline) has been synthesized and structurally characterized. In the crystal structure the two centrosymmetric [Ba2(phen)4(H2O)6] units are bridged through two trans CN groups of [Fe(CN)6]3− ion, which results in the formation of a zig-zag polymeric chain. In each [Ba2(phen)4(H2O)6] unit, the two Ba centers are joined by double aquo bridges. Both the Ba atoms are 9-coordinated with distorted mono-capped square antiprismatic geometry. An elaborate hydrogen bonding system holds the parallel polymeric chains together. 相似文献
136.
Abdul Latif Ahmad Choe Peng Leo Syamsul Rizal Abd. Shukor 《Journal of Porous Materials》2009,16(1):33-40
Porous γ-alumina with well arranged secondary mesopores has been contrived using nanosized templating units. The pore size
of templated mesopores is precisely controlled as the pore shrinkage is insignificant. The primary pore diameter is ca. 4 nm
and the secondary pore diameter is ca. 50 nm. The porous material was characterized using N2 adsorption/desorption, TEM, XRD and FT-IR. γ-alumina with bimodal pore size distribution shows improved intra-particle diffusion
compared to γ-alumina with unimodal pore size distribution in a simple dye adsorption test. γ-alumina with different porous
structures were then impregnated with vanadium oxide for catalytic effect comparison. It was perceived that secondary pores
improve the styrene oxidation rate after the conversion of styrene reaches 30%. 相似文献
137.
138.
Weldalite 050, a high-strength Al-Mg-Li alloy, was evaluated for its corrosion resistance in deaerated and air saturated Arabian
Gulf water to determine its suitability for marine applications. Weight loss and electrochemical studies showed that the alloy
had minimum corrosion rates of 1.82 and 4.82 mpy (mils per year), respectively, in deaerated and air saturated Arabian Gulf
water with very high total dissolved solids (TDS) content. Weldalite 050 exhibited good resistance to corrosion at velocities
up to 3.9 m/s. The formation of Al2MgLi, Al-Li, Al12Mg17, and Al-Li precipitates has a pronounced effect on its corrosion resistance. The corrosion resistance of Weldalite 050 compares
favorably with that of alloys 5052 and 5054, wrought alloys 6061 and 6013, and silicon carbide (SiC) reinforced alloys 6061
and 6013. 相似文献
139.
Commercial fillers, including carbon black (N550), halloysite nanotubes (HNTs), and precipitated silica, were replaced by recycled poly(ethylene terephthalate) powder (R‐PET) in natural rubber (NR) composites. Five different compositions of NR/N550/R‐PET, NR/HNTs/R‐PET, and NR/silica/R‐PET compounds, i.e., 100/20/0, 100/15/5, 100/10/10, 100/5/15, and 100/0/20 parts per hundred rubber (phr), were prepared on a two‐roll mill. The curing behavior, tensile properties, and morphological characteristics of the natural rubber composites were investigated. The results indicated that the replacement of carbon black, HNTs, and silica by R‐PET decreased the tensile strength and tensile modulus, such that NR/silica/R‐PET composites showed the lowest effect, followed by NR/HNTs/R‐PET and NR/N550/R‐PET composites. The negative effect on these properties can be explained by the decrease of crosslink density. The curing results revealed that with the replacement of carbon black by R‐PET, the scorch time and cure time decreased, but that the NR/HNTs/R‐PET and NR/silica/R‐PET composites exhibited the opposite trend. Scanning electron microscopy investigation of tensile fracture surfaces confirmed that the co‐incorporation of N550/R‐PET improved the dispersion of R‐PET and enhanced the interaction between the fillers and NR matrix more than R‐PET and silica/R‐PET hybrid fillers. J. VINYL ADDIT. TECHNOL., 2012. © 2012 Society of Plastics Engineers 相似文献
140.
Haider F. Abdul Amir Abdulah Chik 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(18):3032-3036
The main purpose of this study is to provide the knowledge and data on Deuterium-Tritium (D-T) fusion neutron induced damage in MOS devices. Silicon metal oxide semiconductor (MOS) devices are currently the cornerstone of the modern microelectronics industry. However, when a MOS device is exposed to a flux of energetic radiation or particles, the resulting effects from this radiation can cause several degradation of the device performance and of its operating life. The part of MOS structure (metal oxide semiconductor) most sensitive to neutron radiation is the oxide insulating layer (SiO2). When ionizing radiation passes through the oxide, the energy deposited creates electron-hole pairs. These electron-hole pairs have been seriously hazardous to the performance of these electronic components. The degradation of the current gain of the dual n-channel depletion mode MOS caused by neutron displacement defects, was measured using in situ method during neutron irradiation. The average degradation of the gain of the current is about 35 mA, and the change in channel current gain increased proportionally with neutron fluence. The total fusion neutron displacement damage was found to be 4.8 × 10−21 dpa per n/cm2, while the average fraction of damage in the crystal of silicon was found to be 1.24 × 10−12. All the MOS devices tested were found to be controllable after neutron irradiation and no permanent damage was caused by neutron fluence irradiation below 1010n/cm2. The calculation results shows that (n,α) reaction induced soft-error cross-section about 8.7 × 10−14 cm2, and for recoil atoms about 2.9 × 10−15 cm2, respectively. 相似文献