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991.
介绍了采用添加硫酸、氯化铵,适当提高管式反应器中氨的质量流量和磷酸(体积流量)的比值,适当提高二次氨化量的方法提高磷酸二铵中的氮含量。 相似文献
992.
采用磷酸硼对木材进行改性处理,测定了处理后试材的阻燃性、抗流失性、吸湿性、力学性能.研究结果表明,磷酸硼处理后试材,吸药量达到20.47 kg/m3以上时,垂直燃烧实验可达到到F-0级水平;通过灼烧实验,磷酸硼处理的木粉在500℃灼烧时残留率可达到97.997%;此改性剂具有较好阻燃性能和一定的抗流失性,常压下磷酸硼处理的樟子松试件LRV为50.28%;木材顺纹抗压强度平均下降了 8.67%,无明显变化;木材抗弯曲压强度平均下降了 27.95%.但磷酸硼阻燃剂在高湿条件下有一定的吸湿性,使用性能有待改进,并应注意采取防护措施. 相似文献
993.
Daodong Pan Jinxuan Cao Lili Wang Xiaoqun Zeng 《International Journal of Food Science & Technology》2012,47(1):160-166
Calcium chloride (CaCl2) and phosphates are important additives to improve product quality during meat processing. Response surface methodology was used to study the influence of CaCl2 and phosphates on the hardness, water‐holding capacity (WHC) and ultra‐structure of salt‐soluble goose meat protein gels. The results show that the hardness and WHC of salt‐soluble protein gels increased significantly when CaCl2 concentration was increased and phosphates were added. Scanning electron microscopy showed that tetrasodium pyrophosphate (TSPP) and sodium tripolyphosphate (STPP) had a greater impact on the cross‐linking and pore diameter of the gel networks than sodium hexametaphosphate (SHMP). At the 0.02 m and 4:3:2 of CaCl2 concentration and the ratio of TSPP, SHMP and STPP, hardness and WHC values were 114.55 gf and 96.65%, which corresponded to the prediction value of our model. Further results showed that the hardness and WHC of gels reached the maximum with 0.3% of phosphates levels. 相似文献
994.
介绍了当今铸铁件的发展趋势及对其性能的要求,认为生产优质铸件的基础条件是采用高纯生铁。详细阐述了我国高纯生铁的生产历程和生产方法,对比国内外高纯生铁的指标数据,指出我国高纯生铁生产技术已经成熟,可媲美国外同类产品。 相似文献
995.
Andrei Victor Sandu Alexandra Ciomaga Gheorghe Nemtoi Costica Bejinariu Ion Sandu 《Microscopy research and technique》2012,75(12):1711-1716
This article presents the SEM‐EDX and microFTIR study and the corrosion behavior of new five types of phosphated coatings obtained by coprecipitation in acid aqueous medium of some metal cations, pursuing the influence of the addition of other cations and a moderator of precipitation, on the uniformity and compactness of the layers and on the morphology of dendritic structure of Zn(II) and Fe(II) phosphates. Microsc. Res. Tech. 2012. © 2012 Wiley Periodicals, Inc. 相似文献
996.
Raúl E. Cian Silvina R. Drago Rolando J. González 《International Journal of Food Science & Technology》2012,47(7):1348-1353
The effect of pH on colour and iron content (Fe) of peptide fractions obtained from bovine haemoglobin concentrate (BHC) hydrolysates was studied. Four hydrolysates were obtained using three enzymes: Protex‐6‐L (P), Fungal–Protease–Concetrate (FC) and Flavourzyme (F). BHC and its hydrolysates (P, FC, P + F, FC + F) were fractioned at pH 4.5, 7.0 and 9.5. Solubility and Fe from different fractions were measured. Correlations between CIELAB colour parameters and Fe from different fractions were analysed. The colour from different fractions varied from red to yellow (a* and b* positives). Lightness values (L*) ranged from twenty‐four to seventy. FC4.5 and FC + F4.5 fractions were the clearest and yellow (higher L*, b*, h), while BHC9.5 and P + F9.5 fractions had the lowest values of L*, b* and h. There was an inverse linear relationship between b* and L* parameters and Fe from fractions. This relationship could be associated with the pH of extraction. As pH increases Fe significantly increases and lower b* and L* values were obtained. 相似文献
997.
一般来说,硫是有害元素。但对于灰铸铁来讲,含有少量的硫对于石墨的生核和切削性能都有非常重要的影响。在铸造生产过程中通过加入一定量的硫,提高铁液的含硫量,从而使铸件获得更好的切削性能。 相似文献
998.
Optimization of dielectric heating parameters in the production of high‐voltage LiNiPO4‐core and carbon‐shell ceramics 下载免费PDF全文
Ahmet Örnek 《Journal of the American Ceramic Society》2017,100(12):5668-5680
Excellent core‐shell morphology and nanoscale high‐voltage LiNiPO4@C cathode materials have been synthesized by a low‐level and long‐time microwave and solvothermal synthesis methodology. The effects of the changing physicochemical parameters on the crystal‐quality and electrochemical properties of the products have been evaluated in relation to the cycling stability. X‐ray diffraction analysis shows that it is possible to synthesize phase‐pure LiNiPO4 material when the reaction parameters are carefully elaborated. High‐resolution transmission electron microscopy analysis reveals a core‐shell morphology with a coating thickness of 6‐8 nm for 30 minutes at 180°C solvothermal temperature and time‐spread microwave energy. This mentioned cathode material exhibits the best electrochemical properties, achieving a discharge capacity of 157 mAh·g?1 at a 0.l C current rate, and shows a remarkable 81% capacity retention at the end of the 80th cycle. 相似文献
999.
This study investigated cellular Nicotinamide Adenine Dinucleotide Phosphate (NADPH) fluorescence as a potential indicator of biohydrogen production in Chlamydomonas reinhardtii and a β-NADPH standard. NADPH fluorescence profiles of cultures grown in TAP-S (Tris-acetate phosphate minus sulphur) media, TAP (Tris-acetate phosphate) media and TAP + 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) were subsequently compared. Hydrogen production induced from sulphur depletion was found to correlate directly (r = 0.941) with NADPH over the ten day period. The addition of leachate was used to increase hydrogen yields, and subsequently increased the NADPH concentration by 50%–70%. A direct correlation was observed (r = 0.929) between NADPH and hydrogen when the leachate supplemented media was used. As NADPH is the terminal electron acceptor in the photosynthetic chain, results show that NADPH has a pivotal role in hydrogen production as a carrier molecule. Under sulphur depletion, cellular NADPH fluorescence can be used as an indicator of hydrogen production. 相似文献
1000.