Recent advances in phosphorylation of food proteins: A review

Phosphorylation is a useful method for improving the functional properties of food proteins. In this article, various methods of phosphorylation are reviewed. Dry-heating phosphorylation, a method developed recently, is also introduced. Some characteristics of phosphate groups are involved, and the effects of phosphorylation on the structural changes, the functional properties, and the physiological functions in vitro of food proteins, are discussed. The types of phosphate linkages and the phosphopeptides from phosphorylated proteins are identified. The molten (partially unfolded) conformations of food proteins formed by phosphorylation are discussed. The phosphorylation of food proteins improved a number of functional properties, including heat stability, emulsifying properties, foaming properties, gelling properties, water absorption capacity, oil absorption capacity, and calcium phosphate-solubilizing ability. In vitro physiological function studies of protein (α-lactoalbumin) indicated that the digestibility (ovalbumin) was improved and the inflammatory response (α-lactoalbumin) was suppressed by phosphorylation. Experiments with animals are necessary to evaluate the toxicity and physiological functions of phosphorylated proteins.     

协调pH-磷酸盐加药在乙烯辅锅上的应用

通过协调pH-磷酸盐加药方法在炉水处理中应用，提高炉水及蒸汽品质，减少炉管和用汽设备的结垢。     

Variations in radioactivity of phosphate rocks from different sites in Central Eastern Desert of Upper Egypt

Natural radionuclides in the phosphate rock samples collected from Wadi Batur, Wadi Hegaza and Gabal Abu Had at Eastern Desert were determined using a high resolution 7-ray spectrometer. The experimental results concerning 226Ra, 232Th and their daughters are presented. Analyses of the measured spectra show that 226Ra is distinguished with remarkable activities with average values ranging from 22.4 to 558 Bq/kg, while 232Th activity concentration is in the range of 9.7 to 92.8 Bq/kg. The results of the analyses were found to be in a good agreement with the data obtained by others.     

Determination of uranium in fertilisers using fission track method

Trace contents of uranium in various commercial fertilizers e.g. ureas, superphosphates, diammonium phosphates have been determined using fission track etch technique. The uranium content in ureas varies from .05 to 1.3 mg kg^–1 whereas in superphosphates it varies linearly with phosphate content.     

Behavior of the monophosphate tungsten bronzes (PO2)4(WO3)2m (m = 7 and 8) in the course of electrochemical lithium insertion

The electrochemical lithium insertion process has been studied in the family of monophosphate tungsten bronzes (PO₂)₄(WO₃)_2m, where m = 7 and 8. Structural changes in the pristine oxides were followed as lithium insertion proceeded. Through potentiostatic intermittent technique the different processes which take place in the cathode during the discharge of the cell were analyzed. The nature of the bronzes Li_x(PO₂)₄(WO₃)_2m formed was determined by in situ X-ray diffraction experiments. These results have allowed establishing a correlation with the reversible/irreversible processes detected during the electrochemical lithium insertion.     

Pore structure control of starch processed silicon nitride porous ceramics with near-zero shrinkage

Zirconium phosphate (ZrP₂O₇) bonded silicon nitride (Si₃N₄) porous ceramics were prepared using starch powder as the pore forming agent and pressureless sintering technique. The obtained results show that the porosity of the sintered starch processed 25 wt.% ZrP₂O₇ bonded Si₃N₄ porous ceramics is 36-62.3%. All the samples exhibit surprisingly low linear shrinkage. The pores are formed by the continuous reaction of ZrP₂O₇ at ~ 250 °C and burnout of starch at ~ 550 °C, during which a large amount of pores with pore sizes of less than 0.5 μm and ~ 10 μm are formed.     

Radiological hazards of TENORM in precipitated calcium carbonate generated as waste at nitrophosphate fertilizer plant in Pakistan

The NORM (naturally occurring radioactive material) in phosphate rock is transferred as TENORM (technologically enhanced naturally occurring radioactive material) to phosphatic fertilizers and to the waste generated by the chemical processes. The waste generated at the NP (nitrophosphate) fertilizer plant at Multan in Pakistan is PCC (precipitated calcium carbonate). Thirty samples of the PCC were collected from the heaps of the waste near the fertilizer plant. Activity concentrations of radionuclides in the waste samples were measured by using the technique of gamma ray spectrometry consisting of coaxial type HPGe (high purity germanium) detector coupled with a PC (personal computer) based MCA (multichannel analyzer) through a spectroscopy amplifier. Activity concentrations of ²²⁶Ra, ²³²Th and ⁴⁰K in the waste samples were determined to be 273 ± 23 (173-398), 32 ± 4 (26-39) and 56 ± 5 (46-66) Bq kg⁻¹ respectively. The activity concentration of ²²⁶Ra in the PCC waste was found to be higher than that in naturally occurring calcium carbonate (limestone and marble) and in worldwide soil. Radiological hazard was estimated from indoor and outdoor exposure to gamma rays from the PCC. Indoor annual effective dose was higher than 1 m Sv. Potential radiological pollution in the environment from TENORM in the PCC has also been addressed.     

Biochemical oxygen demand and nutrient processing in a novel multi-stage raw municipal wastewater and acid mine drainage passive co-treatment system

A laboratory-scale, four-stage continuous flow reactor system was constructed to test the viability of high-strength acid mine drainage (AMD) and municipal wastewater (MWW) passive co-treatment. The synthetic AMD had pH 2.60 and 1860 mg/L acidity as CaCO₃ equivalent with 46, 0.25, 2, 290, 55, 1.2 and 390 mg/L of Al, As, Cd, Fe, Mn, Pb and Zn, respectively. The AMD was introduced to the system at a 1:2 ratio with raw MWW from the City of Norman, Oklahoma USA containing 265 ± 94 mg/L BOD₅, 11.5 ± 5.3 mg/L PO₄⁻³, and 20.8 ± 1.8 mg/L NH₄⁺-N. During the 135 d experiment, PO₄⁻³ and NH₄⁺-N were decreased to <0.75 and 7.4 ± 1.8 mg/L, respectively. BOD₅ was generally decreased to below detection limits. Nitrification increased NO₃⁻ to 4.9 ± 3.5 mg/L NO₃⁻-N, however relatively little denitrification occurred. Results suggest that the nitrogen processing community may require an extended period to mature and reach full efficiency. Overall, results indicate that passive AMD and MWW co-treatment is a viable ecological engineering approach for the developed and developing world that can be optimized and applied to improve water quality with minimal use of fossil fuels and refined materials.     

长江经济带磷矿资源开发与生态保护现状分析及对策建议

我国磷矿资源分布和开发利用主要集中在长江经济带的湖北、贵州、云南、四川和湖南五省。本文从长江经济带磷矿资源分布、储量特点,磷矿生产基地现状,磷化工产业现状,磷石膏利用情况和面临的生态环境问题等方面进行了分析。结果表明:长江经济带磷矿资源储量丰富,分布集中,以大中型的沉积型矿床为主,平均品位低,富矿少,地下开采为主,选矿复杂。长江经济带形成了湖北宜昌等8大磷矿生产基地和以磷复肥为基础的现代磷化工产业体系,磷石膏综合利用需进一步提升;面临着矿区与自然保护区冲突,磷化工造成总磷污染严重、磷石膏堆存量大且利用率低等生态环境问题。据此提出了全面推进绿色矿山建设、发展循环经济、探索生态修复新机制等对策,以促进长江经济带磷矿资源开发利用与生态保护协调发展。     

新型捕收剂用于矾山磷矿的选矿试验研究

为了探索矾山磷矿常温浮选的选矿工艺,使用H_(907)和新研制的AW—02作为捕收剂进行了连续扩大试验,在常温和不加碱的浮选条件下,获得了精矿品位约36.70％、回收率约94.5％的较好指标。