溶磷剂与硫杆菌协同对铁矿石脱磷的研究

从铁矿井下废水中采集硫杆菌种，经强化培养，用以转化铁矿石中硫化物，打开溶磷通道，添加溶磷剂ＳＰ－９增加磷的溶出，使铁矿石中磷的含量降低到０．２％以下。该生物技术还可将尾矿废液作为铁－磷复合肥料进行开发，减少环境污染并扩大国产资源的综合利用。

Effects of Metal Ions and Organic Solvents on Alkaline Phosphatase from Rice-field Eel

[Objective]The mechanism of alkaline phosphatase（ALP） was studied to promote rice-field eel aquaculture industry. [ Method] The effects of effectors such as multiple metal ions and organic solvents on ALP in viscera of rice-field eel. [ Result] Na^＋ and K ^＋ didn＇t generate big influences on enzyme activity;Mg^2＋ and Ca^2＋ could promote ALP while Li^＋,Cu^2＋ and Zn^2＋ could restrain ALP enzyme activity. Both HPO4^2- and WO4^2- generated by en- zyme catalyzing disodium phenyl phosphate possessed strong inhibitory effects on emzymc, and 9.5 mmol/L HPO4^2 - would make enzyme activity decline by 13% while 9.5 mmol/L WO4^3- would make enzyme decline by 34%. The inhibition types of them were both competitive inhibition on enzyme activity. The organic solvents such as methanol, ethanol,ethylene glycol,isopropannl all generated influences on ALP and the order according to their inhibitory effects was isopropanol 〉 ethanol 〉 methanol 〉 ethylene glycol. [ Conclusion] The inflncnces of various effeetors on ALP aetivity of rice-field eel were studied from dynamics perspective to provide theoretical basis for further clarifying ALP mechanism.

Solvent extraction kinetics of Sm(Ⅲ),Eu(Ⅲ) and Gd(Ⅲ) with 2-ethylhexyl phosphoric acid-2-ethylhexyl ester

Solvent extraction kinetics of Sm（Ⅲ）, Eu（Ⅲ） and Gd（Ⅲ） from hydrochloric acid have been focused on using 2-ethylhexyl phosphoric acid-2-ethylhexyl ester （P507） with Anordning for Kontinuerlig Undersokning av Fordelningsfaktore rid Vatske Extraction （AKUFVE）. Compared with the conventional set-up, some advantages emerge obviously, for example, fast phase separation, easy operation and convenience of kinetic data acquisition. First of all, the extraction mechanism was discussed based on the dimeric model of P507. Secondly, the effects of stirring speed were investigated and 420 r-min-1 was determined of the following experiments. The effects of pH, concentration of rare earth elements （REEs） and P507 on the extraction rate were analyzed. The results indicated that the extraction mechanism changed with the increasing concentration of P507. Then, the experiments with different temperature were carried out. It turned out that the values of apparent activation energy （Ea） for Sm（Ⅲ）, Eu（Ⅲ） and Gd（Ⅲ） extracted by P507 were 26.80 kJ-mol-1, 13.40 kJ.mol-1 and 1.10 kJ- mol- 1 respectively, the resistance of the entire process was limited by diffusion or both of diffusion and reaction. Finally, the correlation equations were obtained, and the theoretical results fit with the experimental data well, most relative error was within ± 30%.

Coordination leaching of tungsten from scheelite concentrate with phosphorus in nitric acid

A hydrometallurgical process for tungsten extraction and recovery from scheelite is reported.The technology includes leaching scheelite using phosphoric acid as chelating agent in nitric acid solutions,extracting tungsten by solvent extraction and reusing leaching agent.In the leaching process,affecting factors,such as temperature,leaching time,nitric acid and dosage of phosphoric acid,were examined on recovery of tungsten.Results show that more than 97%of tungsten could be extracted under conditions of leaching temperature of 80-90°C,HNO3 concentration of 3.0-4.0 mol/L,liquild-to-soild ratio of 10:1,H3PO4 dosage of 3 stoichiometric ratio and leaching time of 3 h.Solvent extraction was then employed for the W recovery from the leachate with a organic system of 40%(v/v)N235,30%(v/v)TBP,and 30%sulfonated kerosene.Approximately 99.93%of W was extracted and ammonium tungstate solution containing 193 g/L W was obtained with a stripping rate of 98.10%under the optimized conditions.

Interaction of Puerarin with Phospholipid in Solid Dispersion

Aim To study the interaction of puerarin (PU) with phospholipid (PL) in soliddispersion. Methods PU/PL solid dispersion was prepared with solvent evaporation and theinteraction between PU and PL was studied by analysis of their ultraviolet spectra, infraredspectra, ~1H NMR spectra and thin layer chromatogram. Results In chloroform the maximum absorptionpeak of PU in PU/PL mixture was located at 243 nm, but 251 nm for that of PU in solid dispersion.However in methanol, QU in mixture or solid dispersion had the same maximum absorption peak locationin ultraviolet spectra. Compared with the infrared spectra of mixture, that of solid dispersionshowed the specific absorption peak location of benzene ring framework in PU molecule was markedlychanged, the stretching vibration peak of P= O in PL molecule was shifted to high wavenumbers andthe stretching vibration peak of C = C in PL molecule was disappeared. In ~1H NMR spectra, most ofthe signals from PU in solid dispersion were weaken markedly or disappeared and the signals from thepolar part of PL molecule were significantly changed. PU and PL in solid dispersion could beseparated on silica gel plate with the mixed solvent of chloroform, methanol and water (65:25:5) orethyl acetate and methanol (10:1) . Conclusion In solid dispersion the benzene ring framework of PUmolecule could act with the polar part and unsaturated part of PL molecule through charges transfer,and the interacted part could be surrounded by fat chains of PL molecule.

Scalable synthesis of ultra‐small Ru_(2)P@Ru/CNT for efficient seawater splitting

In this study,an ultra‐fast and simple solvent‐free microwave method was successfully demonstrated using a series of ultra‐small(~2.5 nm)surfactant‐free Ru_(2)P@Ru/CNT heterostructures for the first time.The structure has a high‐density Ru component and Ru_(2)P component interface,which accelerates the hydrogen evolution reaction(HER).The prepared Ru_(2)P@Ru/CNT demonstrated excellent catalytic effects for the HER in alkaline media and real seawater.The experimental results indicate that ratio‐optimized Ru_(2)P@Ru/CNT(Ru_(2)P:Ru=66:34)requires only 23 and 29 mV to reach 10 mA cm^(-2)in 1.0 mol/L KOH and real seawater,respectively.These values are 10 and 24 mV lower than those of commercial Pt/C in 1.0 mol/L KOH(33 mV)and real seawater(53 mV),respectively,making it among the best non‐Pt HER reported in the literature.Additionally,the TOF of Ru_(2)P@Ru/CNT in alkaline freshwater and seawater were 13.1 and 8.5 s^(-1),respectively.These exceed the corresponding values for Pt/C,indicating that the catalyst has excellent intrinsic activity.The high current activity of Ru_(2)P@Ru/CNT in 1.0 mol/L KOH was explored,and only 77 and 104 mV were required to reach 500 and 1000 mA cm^(-2),respectively.After 100 h of durability testing,the catalyst retained excellent catalytic and structural stability in low current density,high current density,and seawater.

Mathematical model and reaction mechanism of molybdenum and tungsten extraction with TRPO from peroxide solution

To understand the behavior of molybdenum and tungsten extracted by tri-alkyl phosphine oxide(TRPO)from peroxide solution,the extraction mechanism was studied by slope method and Raman and FTIR spectroscopy.The empirical formulas of molybdenum and tungsten extraction distribution ratio(D_(Mo)and D_(W))as functions of equilibrium pH,TRPO concentration and temperature were obtained by establishing mathematical models.Furthermore,the reliability of the empirical formula was verified in the H^(+)-W-Mo-H_(2)O_(2) solution.The results indicate that the calculated values of D_(Mo)or D_(W)were consistent with the experimental values.The apparent extraction equilibrium constants of molybdenum and tungsten wereK_(Mo)^(app)=8.51×10^(3)(0.74≤pH_(e)≤1.7),K_(Mo)^(app)=99.89×10^(3)(1.7<pH_(e)≤4.62)andK_(W)^(app)=2.65×10^(3)(0.92<pH_(e)<2.16)at 20°C,respectively.The main extraction complex of molybdenum or tungsten was[H_(2)(Mo or W)_(2)O_(3)(O_(2))_(4)(H_(2)O)_(2)]·2TRPO.These empirical formulas can be used to analyze and estimate the extraction and separation of Mo and W from low molybdenum and tungsten concentration solutions.

Solvent Extraction of Alkaline Earth Metals with Alkylphosphorus Acids

Solvent extraction equilibria of four main alkaline earth metals(magnesium, calcium, strontium and barium) with di (2-ethylhexyl)phosphoric acid (DEHPA), 2-ethylhexyl phosphonic acidmono-(2-ethylhexyl) esters, di (2, 4, 4-tri-methylpentyl) phosphinicacid and IR spectra of the extracts have been studied. Theselectivity order is dependent on the e/r value and hydration energyof the metal ions. The minor shift of the P→O in IR absorption ofthe alkaline earth metal extracts indicates that the interactionbetween the metal ions and P→O is much weaker for alkaline earthmetals than for transitional metals.

Solvothermal Synthesis and Optical Performance of One-dimensional Strontium Hydroxyapatite Nanorod

One-dimensional strontium hydroxyapatite （Sr-HAp） nanorods were successfully synthesized by a simple solvothermal method. The products were characterized via X-ray diffraction （XRD）, Fourier transform infrared （.FT-IR）, .cold field emission.sc.anning.elec.tron microscopy_.（FESEM）, transmission.electron microscopy （TEM）,photoluminescence （PL） excitation and emission spectra. The experimental results indicated that oleic acid as a surfactant played a key role in confining the growth of the Sr-HAp powders. A possible formation mechanism of the one-dimensional nanorod was proposed and elaborated. Moreover, the as-obtained Sr-HAp samoles showed an intense and bright emission band centered at 460 nm under long-wavelength UV light excitation and the contents of NaOH used in the synthetic process had an obvious impact on the optical performance of Sr-HAp powders. The possible luminescent mechanism of the Sr-HAp samples was discussed.

ahospholipase Applications in Cheese Production

Phospholipase is an enzyme that hydrolyzes phospholipids releasing a variety of products, like for example lyso-phospholipids, free fatty acids, di-acylglycerols, choline phosphate and phosphatidates, depending on the site of hydrolysis. In cheese production, lysophospholipids act as surface-active agents in the cheese curd, helping emulsification of water and fat during processing and reducing syneresis. Phospholipases are more specific and have little or no activity toward di- or triglycerides. As a result of phospholipid hydrolysis, flavor defects do not occur due to the main formation of palmitic, oleic, and stearic acids, which are non-volatile short chains fatty acids. According to the scientific studies the use of phospholipase is able to increase the yield of cheese and reduce the environmental impacts of cheese production. Protein and fat largely determine cheese yield. Depending on the milk composition, 75% to 78% of milk protein and 85% to 95% of milk fat are entrapped in the cheese curd. The remaining protein and fat are lost in the whey and, to a lesser extent, in the brine. Crucially in the production of pasta filata cheese fat losses occur in the hot stretching step, where the fresh curd is molded and stretched in hot water. The lysophospholipid-casein complexes should be studied to understand the mechanism leading to cheese yield improvements.

Effects of different enzymatic hydrolysis methods on the bioactivity of peptidoglycan in Litopenaeus vannamei

The effects of different hydrolysis methods on peptidoglycan （PG） were assessed in terms of their impact on the innate immunity and disease resistance of Pacific white shrimp, Litopenaeus vannamei. PG derived from Bifidobacteriurn thermophilum was prepared in the laboratory and processed with lysozyme and protease under varying conditions to produce several different PG preparations. A standard shrimp feed was mixed with 0.05% PG preparations to produce a number of experimental diets for shrimp. The composition, concentration, and molecular weight ranges of the soluble PG were analyzed. Serum phenoloxidase and acid phosphatase activity in the shrimp were determined on Days 6-31 of the experiment. The protective activity of the PG preparations was evaluated by exposing shrimp to white spot syndrome virus （WSSV）. Data on the composition of the PG preparations indicated that preparations hydrolyzed with lysozyme for 72 h had more low-molecular-weight PG than those treated for 24 h, and hydrolysis by protease enhanced efficiency of hydrolysis compared to lysozyme. SDS-PAGE showed changes in the molecular weight of the soluble PG produced by the different hydrolysis methods. Measurements of serum phenoloxidase and acid phosphatase activity levels in the shrimp indicated that the PG preparations processed with enzymes were superior to the preparation which had not undergone hydrolysis in enhancing the activity of the two serum enzymes. In addition, the preparation containing more low-molecular-weight PG enhanced the resistance of the shrimp to WSSV, whereas no increased resistance was observed for preparations containing less low-molecular-weight PG. These findings suggest that the immunity-enhancing activity of PG is related to its molecular weight and that increasing the quantity of low-molecular-weight PG can fortify the effect of immunity enhancement.

Lubricating properties of polyalkylene glycol and organic phosphate ester mixed aqueous solutions

Till now,water based lubricants,especially aqueous solutions,have not been employed in the elastohydrodynamic lubrication(EHL)due to their poor film forming capability or low wear resistance.In this paper,we proposed a method to develop water based lubricant:employing polyalkylene glycol solution as base stock to improve EHL film forming capability and using organic phosphate ester(DPZ)as anti-wear additive to improve wear resistance property.The lubricating properties of the mixed solutions,including load carrying capability,wear resistance property,friction reduction property,EHL film forming behavior,were investigated.The experimental results indicate that the mixed solution presents excellent lubricating properties,which make it a promising candidate in developing water based lubricants.