共查询到20条相似文献,搜索用时 15 毫秒
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Juana FernndezLpez Jos Angel PrezAlvarez Vicente ArandaCatal 《Color research and application》2000,25(5):376-380
Although the colour of different meat products has been studied, particularly in the final product , these studies do not separate the influence of degree of mincing from other factors such as additives, spices, manufacturing process, etc. The effect of degree of mincing on colour (CIELAB colour space) in pork meat was studied. Three mincing processes were studied, two using a grinder with 10 and 20 mm diameter holes in the plate, and a third in which a cutter was used to obtain a finely minced product. As control, intact meat was used. Colour parameters [lightness (L*), redness (a*), yellowness (b*), chroma (C*), hue (H*), a*/b* ratio, and colour differences], pH, and water holding capacity were determined. Mincing, regardless of the type used, increased the values of L*, b*, and H*, but decreased the values of a* and a*/b* ratio. The L* values increased with mincing degree. The H* values and a*/b* ratio of plate minced meats (10 and 20 mm) differed from that which had been finely minced. The mincing process did not modify the saturation values of the batters. Only the fine mincing process modified (increased) the water holding capacity of the batters. © 2000 John Wiley & Sons, Inc. Col Res Appl, 25, 376–380, 2000 相似文献
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磷酸型两性淀粉一步合成反应机理研究 总被引:3,自引:0,他引:3
通过木薯淀粉与3-氯-2-羟丙基三甲基氯化铵及三聚磷酸钠、磷酸二氢钠/磷酸氢二钠,在不同反应介质、不同酸碱性条件下合成的对比实验,以及三聚磷酸钠在水和水.乙醇反应介质中的各自性质变化测定分析,研究了同时进行阴、阳离子化反应磷酸型两性淀粉一步合成的机理。结果表明:在碱性的水-乙醇介质中,三聚磷酸钠水解可被有效抑制,而以酸酐结构的分子状态存在;用三聚磷酸钠作为阴离子化反应试剂一步合成磷酸型两性淀粉,反应过程中三聚磷酸钠保持酸酐结构、阳离子基团上存在负氧离子是同时引入季铵型阳离子、磷酸型阴离子的关键。 相似文献
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为了解决磷酸盐生产企业装置多、规模小、分布广、竞争力弱等问题,笔者认为有必要在分布广、数量多、产能大的干燥聚合两步法的三聚磷酸钠装置上进行多功能化研究。论述了三聚磷酸钠装置多功能化研究的重要性与必要性、可能性与可行性,在实践的基础上阐述了一种以热法干燥聚合两步法在一套三聚磷酸钠装置上实现多种磷酸钠盐生产的系统方法和技术。经过实践检验,证明该系统方法和技术是完全可行的。同时,在此基础上对磷酸钾盐、磷酸钙盐与磷酸钠盐实现生产装置的同一化提出了大胆设想,为磷酸盐生产探索新的技术思路和发展模式。 相似文献
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采用水-溶剂低热合成方法,通过分子设计合成了一种三聚磷酸钠(STPP)的环氧官能团化杂化树脂(PEHRs),通过分离与提纯,采用薄层色谱法(TLC)、FT-IR、DSC等对杂化材料的结构和热性能进行了初步的表征研究。结果发现,产物是一类结构中既有Me-O-P键构成的线性骨架,又有以P-O-C共价键形式结合的网络结构的新型杂化树脂。其物性特征为透明凝胶状,可溶于N,N-二甲基甲酰胺,软化点为75 ̄85℃,加热可以熔融,拉伸可以发生取向,并采用甲基纳迪克酸酐(MNA)等固化剂对PEHRs进行固化,杂化树脂的合成和固化的实现表明其具有很高的研究价值和应用前景。 相似文献
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在Ca^2+浓度一定的条件下,分别改变碳酸钠、三聚磷酰钠的浓度,通过测定溶液的透光率,研究了三聚磷酸钠对碳酸结晶的影响。 相似文献
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在制取取代度为0.01~0.02的碎米淀粉磷酸酯化的实验中,考察了pH值、反应温度、反应时间、尿素用量和磷酸盐用量对酯化反应的影响,结果表明,磷酸盐用量(与淀粉的干重比)为0.0402,pH值为5.1,反应温度为150 ℃,反应时间105 min时,酯化淀粉的粘度值为3 850 mPa·s. 相似文献
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氯化钠法制备氯化锂的工艺研究 总被引:1,自引:2,他引:1
研究了以硫酸锂和氯化钠为原料制备氯化锂的方法,硫酸锂与氯化钠在室温条件下1:1(体积比)反应,反应液经减压浓缩后于-5℃温度下完全析出硫酸钠晶体,继续浓缩反应液得到氯化锂的饱和溶液,冷却结晶。其工艺简单,成本较低,所得氯化锂产品能达到一级品的要求,且收率在95%(质量分数)以上。 相似文献
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B. Rivard D. Lyder J. Feng A. Gallie E. Cloutis P. Dougan S. Gonzalez D. Cox M.G. Lipsett 《加拿大化工杂志》2010,88(5):830-838
Oil sand is a mixture of quartz grains, clay minerals, bitumen, water, and minor accessory minerals. There is a need in oil sands mining operations for a robust method to estimate total bitumen content in real time; and so modelling of the total bitumen content (TBC) in Athabasca oil sands of Western Canada was undertaken on the basis of hyperspectral reflectance spectra. A selection of different bitumen, water, and clay mineral spectral features (3.0–30.0 µm) was used to develop broad‐band TBC predictive models that have good accuracy, with less than 1.5% error with respect to laboratory methods of bitumen assay. These models are also robust, in that they are independent of mine location. Simple broad band models, based upon previously identified Gaussian features or wavelet features, provide an incremental improvement over the currently deployed industry two‐band ratio model. An improved two‐band model was also developed, which makes use of a combination of the same two bands but normalised to their mean. A wavelet‐based, broad‐band model comprised of indices and five bands, where the bands are normalised to the mean of the bands, adequately addresses the influence of water, clay, and textural variation on selected bitumen features. This five‐band model appears to produce the most robust estimator of TBC, with a dispersion of ∼1.1–1.5%, which can be applied to different sites within a mine and to different mines without additional tuning or calibration, as evidenced by regression slopes of 0.99–1.0 for modelling, validation, and blind data sets. 相似文献
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采用对氨基苯磺酸-盐酸萘乙二胺光度法测定三聚磷酸钠中亚硝酸盐,探讨了样品处理与干扰消除方法,控制溶液pH为3.0左右,溶解样品时避免加热水解,必要时对溶液进行干过滤,测定结果变异系数为2.3%,回收率为98.6%~100.6%。 相似文献
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研究发现表面活性剂对氯化钠水溶液的结晶行为有严重的影响,通过研究表面活性剂与氯化钠水溶液体系的黏度,进而认识表面活性剂对氯化钠结晶的影响机理。 相似文献
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氯化钠浮选动力学研究 总被引:3,自引:0,他引:3
氯化钠的浮选动力学研究对工业生产具有指导作用,因此本文用混合浮选剂对盐湖钾镁硫酸盐混矿中的氯化钠进行了浮选动力学研究,并给出了动力学方程:ε=0.2264 e-0.1704t 0.7736 e-0.8165t. 相似文献
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Michel J.A.M. van Putten Christoph Fahlke Karl W. Kafitz Jeannette Hofmeijer Christine R. Rose 《International journal of molecular sciences》2021,22(11)
Ischemic stroke is a leading cause of mortality and chronic disability. Either recovery or progression towards irreversible failure of neurons and astrocytes occurs within minutes to days, depending on remaining perfusion levels. Initial damage arises from energy depletion resulting in a failure to maintain homeostasis and ion gradients between extra- and intracellular spaces. Astrocytes play a key role in these processes and are thus central players in the dynamics towards recovery or progression of stroke-induced brain damage. Here, we present a synopsis of the pivotal functions of astrocytes at the tripartite synapse, which form the basis of physiological brain functioning. We summarize the evidence of astrocytic failure and its consequences under ischemic conditions. Special emphasis is put on the homeostasis and stroke-induced dysregulation of the major monovalent ions, namely Na+, K+, H+, and Cl−, and their involvement in maintenance of cellular volume and generation of cerebral edema. 相似文献
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详细地阐述了以元明粉生产过程中的半成品(即离心机分离的湿元明粉)90硝为原料,经过溶解、除钙镁、调pH、蒸发、分离、干燥等一系列工序,生产出符合《化学试剂无水硫酸钠》GB/T 9853—2008技术指标的分析纯元明粉。主要中控参数:溶液pH为3~6,蒸发终点控制在母液中Ca2+质量浓度≤0.55 g/L。该工艺生产分析纯元明粉,具有工艺过程简单,产品溶解性好、纯度高、质量稳定,辅料廉价易得,生产成本小、利润空间大等优点,值得在高纯元明粉行业推广应用。 相似文献
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为探究铁磷酸盐玻璃对含钠核废物的包容特性,了解Na2O对其微结构的影响.采用熔融-冷却法制备xNaO-(100-x)(40Fe2O3-60P2O5)(0≤x≤50mol%)系列玻璃样品.利用XRD、Raman和FT-IR等手段对玻璃微观网络结构进行表征,对振动光谱的谱带归属进行了指认.结果表明:所有样品均为均质玻璃,铁磷酸盐基础玻璃结构以Q1结构单元为主,伴随Na2O含量的增加,Q1结构单元逐渐减少,Q0结构单元数量逐渐增加,同时形成了P-O-Na+离子键.在Na2O含量40mol%时,Q1结构单元特征谱峰消失.Na2O的引入,引起磷酸盐网络中非桥氧键增加桥氧键减少,导致磷酸盐玻璃结构解聚,微观网络结构松弛. 相似文献
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在正浮选法制备氯化钾过程中,由于氯化钠与氯化钾一同浮出而影响了氯化钾产品的质量,因此有必要针对氯化钠随氯化钾浮出的行为进行研究。在25 ℃条件下,考察了氯化钠浓度对氯化钾-氯化钠和氯化镁-氯化钾-氯化钠两种浮选液黏度的影响,以及在这两种溶液中氯化钠的粒径对氯化钠的沉降速率、氯化钠的回收率、氯化钾产品质量的影响。结果表明,正浮选中氯化钠随氯化钾浮出的主要原因是浮选液的黏度较大,粒径较小的氯化钠颗粒易黏附于气泡表面或进入氯化钾矿化泡沫层而被夹带浮出。当氯化钠颗粒大于125 μm时,可有效减小氯化钠对氯化钾浮选的干扰,提高氯化钾产品的质量。 相似文献