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101.
“十一五”规划重点突出了“科学的发展观”,“自主创新”与“节约型循环型经济增长”等概念,印刷业的环保、节约资源自然也就成了议论热点。然而宏观层面的问题尽管是头等大事,但对业主或厂主们来说毕竟还是缺乏饥寒忧患的迫切感。老实说,目前印企老总们最关心的还是业务、工价和盈利这老三样。如果同时召开一个环保问题和一个开拓业务问题的会议,前者的参与者肯定没有后者踊跃。 相似文献
102.
Bo Che Liwei Lu Longfei Liu Yan Yang Wei Kang Jun Luo Zhiqiang Wu Yongfeng Qiu 《金属学报(英文版)》2023,36(3):469
The mechanical behavior of solution heat-treated and pre-aged Mg-6Zn-1Gd-1Er alloys during hot compression (from 180 to 330 °C) has been investigated. The results showed that the flow stress curves of the pre-aged sample (PAS) intersected with that of the solution heat-treated sample (SHTS) during hot compression. At 180 °C, when the true strain is 0.27 and 0.47, the PAS showed larger and smaller stress (210.80 MPa vs. 207.58 MPa and 205.67 MPa vs. 207.93 MPa) than the SHTS, respectively. These phenomena were due to the stronger interaction of W phase and dislocations/twins under the strain of 0.27, while dynamic recrystallization softening occurred under the strain of 0.47. When the temperature increased to 330 °C, the flow stress of PAS and SHTS showed an opposite trend to that of 180 °C. Continuous dynamic recrystallization and particle stimulated nucleation based on slip operations are the main deformation mechanisms under 330 °C. At the true strain is 0.33 and 0.53, the PAS has smaller and larger stress (61.32 MPa vs. 63.69 MPa and 58.75 MPa vs. 57.09 MPa) than the SHTS, respectively. The increasing deformation resistance of dynamic precipitation improved the flow stress under smaller strain and dynamic recrystallization decreased the flow stress under high strain, which resulted the opposite phenomena of SHTS. 相似文献
103.
Fourier transform infrared (FTIR) spectroscopy with transmission cell is described to predict anisidine value of palm olein.
The calibration set was prepared by mixing the thermally oxidized palm olein and the unoxidized palm olein with certain ratios
(w/w) covering a wide range of anisidine values. A partial least square (PLS) regression technique was employed to construct
a calibration model. This model was further accomplished by a validation step. The standard error of prediction found was
0.51. The precision of this method was shown to be comparable to the accuracy of the American Oil Chemists’ Society method
used for measurement of anisidine value, with coefficient of determination (R
2) of 0.99. The study showed that mid-band FTIR spectroscopy combined with a PLS calibration technique is a versatile, efficient,
and accurate technique for the estimation of anisidine value of palm olein within about 2 min with less than 2 mL of sample. 相似文献
104.
J. M. N. Marikkar S. L. Ng Y. B. Che Man 《Journal of the American Oil Chemists' Society》2011,88(6):749-754
Composition and thermal profiles of the endogenous lipids of ten commercial chicken nuggets brands (NPO, ACO, AFO, APO, ASO,
AMO, ARO, JOD, SMO, and SOD) were compared with those of the lipids of chicken nuggets pre-fried in lard (ALD) and palm olein
(AOO) to determine the type of oil used for pre-frying of the product. The stearic acid content of the commercial brands were
similar to that of the sample pre-fried in palm olein, but significantly (p < 0.05) lower than that of the sample pre-fried in lard. The triacylglycerol (TAG) profiles of the commercial brands were
similar to that of the sample pre-fried in palm olein, but distinctly different from the sample pre-fried in lard according
to the dissimilarities in the contents of TAG molecules namely, PLL, POS, and PPO. Based on thermal analysis, the commercial
brands of chicken nuggets could be divided into three distinguishable subgroups namely, Group-A: NPO; Group-B: ACO, AFO, APO,
ASO; Group-C: AMO, ARO, JOD, SMO, SOD. While brands under group-B showed close similarity to AOO, none show any similarity
to sample ALD. As any of the samples did not possess characteristics of the sample pre-fried in lard, the commercial brands
of chicken nuggets of this study are recommendable for consumers whose religious restriction prevents the use of lard in food. 相似文献
105.
M. Nurjuliana Y. B. Che Man D. Mat Hashim 《Journal of the American Oil Chemists' Society》2011,88(1):75-82
An electronic nose was successfully used to detect and discriminate lard from other types of animal body fats and samples containing lard. The results are presented in the form of VaporPrint™, the image of the polar plot of the odor amplitudes from the surface acoustic wave (SAW) detector frequency. In the VaporPrint™, the radial angles representing the sensor provides individual fingerprints of the aroma of different animal body fats. Principal component analysis (PCA) was used to interpret the data and it provided a good grouping of samples, with 61% of the variation accounted for by PC 1 and 29% accounted for by PC 2. All of the lard-containing samples formed a separate group from the samples that were free from lard. This method can be developed into a rapid method for detecting the presence of lard in food samples for Halal authentication. 相似文献
106.
Wai-Fun Leong Kok-Whey Cheong Oi-Ming Lai Kamariah Long Yaakob B. Che Man Misni Misran Chin-Ping Tan 《Journal of the American Oil Chemists' Society》2011,88(5):717-725
The purpose of this study was to optimize the production parameters for water-soluble phytosterol nanodispersions. Response surface methodology (RSM) was employed to model and optimize three of the processing parameters: mixing time (t) by conventional homogenizer (1–20 min), mixing speed (v) by conventional homogenizer (1,000–9,000 rpm) and homogenization pressure (P) by high-pressure homogenizer (0.1–80 MPa). All responses [i.e., mean particle size (PS), polydispersity index (PDI) and phytosterols concentration (Phyto, mg/l)] fitted well to a reduced quadratic model by multiple regressions after manual elimination. For PS, PDI and Phyto, the coefficients of determination (R 2) were 0.9902, 0.9065 and 0.8878, respectively. The optimized processing parameters were 15.25 min mixing time, 7,000 rpm mixing speed and homogenization pressure 42.4 MPa. In the produced nanodispersions, the corresponding responses for the optimized preparation conditions were a PS of 52 nm, PDI of 0.3390 and a Phyto of 336 mg/l. 相似文献
107.
108.
Hongwei Che Shuhua Han Wanguo Hou Aifeng Liu Shasha Wang Yuanyuan Sun Xiaoyan Cui 《Journal of Porous Materials》2011,18(1):57-67
A novel strategy involving the combination of soft-templating and solid–liquid method (CSSL) is presented to synthesize mesoporous
nanocrystalline zirconia with high specific surface area, that is, the mesostructured zirconia hybrid is firstly synthesized via cooperative assembly between zirconium sulphate as inorganic
precursor and 1-hexadecyl-3-methylimidazolium bromide (C16mim+Br−) as the structure-directing agent, and subsequently ground with solid magnesium nitrate salt followed by heat-treatment in
air. The resulting zirconia material after calcination at 600 °C possesses a wormlike arrangement of mesopores surrounded
by tetragonal ZrO2 nanocrystallites of ca. 2.3 nm. The BET surface area is 255 m2/g and the pore size is ca. 4.3 nm. However, no mesoporous structure exists in the obtained zirconia material via the simple soft-templating method at
the same calcination temperature. Photoluminescence (PL) spectra of the obtained mesoporous nanocrystalline ZrO2 show a strong emission peak at ca. 394 nm under UV excitation of 250 nm wavelength. 相似文献
109.
Jingshuai Yang Quantong Che Lu Zhou Ronghuan He Robert F. Savinell 《Electrochimica acta》2011,(17):5940
High temperature proton exchange membranes based on Nafion were prepared by incorporating the polymer with ionic liquid cation 1-butyl-3-methylimidazolium (BMIm) and doping with phosphoric acid (PA). We found that using the hydroxide form rather than the chloride form of BMIm incorporated more readily the BMIm cation into Nafion film. A mole ratio of about 2 of BMIm cation to Nafion repeat unit, i.e., λBMIm/Nafion, was reached with the hydroxide form BMIm. The incorporated BMIm cation enhanced the doping of phosphoric acid into Nafion. A proton conductivity of 10.9 mS cm−1 and a tensile stress at break of 5.3 MPa were achieved, respectively, with a composite membrane of Nafion/2.3BMIm/5.2PA in molar ratio at 160 °C without humidification. 相似文献
110.
Yuanyuan Che Zhanglong Sun Ruirui Zhan Shuzhan Wang Shaofeng Zhou Jin Huang 《Ceramics International》2018,44(15):18067-18077
In this work, graphene oxide sheets-zirconia spheres (ZrO2-rGO) nanohybrids were fabricated by Schiff base or Michael addition reaction. Their structure was characterized by FT-IR spectroscopy, UV–vis absorption spectra, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and atomic force microscope in detail. The reaction process of PDA-capping on rGO and APTES treatment on ZrO2 nanoparticles were verified and it was proved that the ZrO2 nanoparticles were successfully adhered onto the wrinkled surface of the graphene oxide. As a new multifunctional nanofillers, the ZrO2-rGO nanohybrids were introduced into epoxy matrix and the mechanical, thermal properties and tribological performances of the fabricated composites were also detailedly investigated. Compared with the neat EP composites, the tensile strength and elongation at break of 0.1?wt% ZrO2-rGO/EP are improved by 33% and 40%, respectively. Besides, the propagation of decomposition reactions in the composites could be impeded by anchoring ZrO2 nanoparticles on the lamellar skeleton of graphene oxide. Furthermore, the lubricating effect and strong interfacial interaction contributed by the ZrO2-rGO nanohybrids result in efficient load transfer from the matrix to the hybrids, which enables the ZrO2-rGO/EP composites to have a fairly high wear resistance performance. This novel and effective approach using ZrO2-rGO nanohybrids as multifunctional nanofillers could be beneficial to promote the development of high performance composites. 相似文献