秸秆灰物相分离及硫酸钾镁肥的制备

以发电厂秸秆灰为原料,用水溶法得到含钾溶液,继而用萃取法分离溶液中的钾与钠,最终获得钾镁肥。确定了水溶法制备含钾溶液的优化工艺参数,即水灰质量比为4∶1、浸取温度为60℃、浸取时间为60 min,在此条件下提钾率达到80.74%。通过正交实验获得萃取分离法制备钾镁肥的优化工艺条件,即萃取剂三正丁胺与正丁醇的体积比为1∶2.5、萃取剂(有机相)与含钾溶液(无机相)的体积比为1∶2、萃取时间为2 h、萃取温度为60℃,在优化工艺条件下制备的钾镁肥符合钾镁肥国家标准,并优于优等品指标。

硝酸浸取铁矿石中磁黄铁矿和磁铁矿的物相分离

永久磁铁棒(呈条形或圆柱状)外套铜套有效磁场为(900±100)×103A/m时,采用人工反复磁选分离,获得的磁性矿物的含铁总量为磁性铁(含磁黄铁矿)。磁性铁用(15+85)硝酸作浸取剂,在加热情况下,磁黄铁矿迅速被硝酸氧化成硫酸盐而溶解,磁铁矿等磁性氧化物则不被溶解而留在残渣中。过滤滤液测定磁黄铁矿,残渣经过焙烧除硫后盐酸溶解测定磁铁矿。

全自动矿物分析仪在砷矿化学物相分析样品加工粒度选择中的应用

化学物相分析样品的粒度对其物相分析结果的影响众所周知,但如何控制样品的粒度,鲜见系统的研究报道。实验在验证建立我国具有代表性砷矿石的化学物相分析方法的过程中,通过对照不同粒度的样品其砷矿物相分析结果,分析各相态之间的变化,得出2类砷矿试样(以雌黄雄黄为主的砷矿和以毒砂为主的砷矿)的粒径均应控制在小于0.100mm,才能使其化学物相分析的结果准确可靠;同时将全自动矿物分析仪(MLA)应用于不同粒度试验样品砷矿物单体解离度的测定,将物相分析结果的变化与相关矿物的单体解离度联系起来,从而证实试样粒度对矿石化学物相选择性分离的影响与其物相单矿物的解离度有关,对于以雌黄和雄黄为主的砷矿,当雌黄和雄黄的单体解离度大于75%时,其物相分析结果是准确可靠的,而对于以毒砂为主的砷矿,样品的加工粒度应控制毒砂的单体解离度大于88%为宜。

Ultrasonic Study on Charge Ordering in Nd0.5Ca0.5Mn1-xAlxO3(x=0,0.03)

The ultrasonic, magnetic and transport properties of Nd0.5Ca0.5Mn1-xAlxO3 （x=0, 0.03） were studied from 15 to 300 K. The temperature dependencies of resistivity and magnetization show that Nd0.5Ca0.5MnO3 undergoes a charge ordering transition at TCO-257 K. An obvious softening of the longitudinal sound velocity above TCO and a dramatic stiffening below Too accompanied by an attenuation peak were observed. These features imply a strong electron phonom interaction via the Jahn-Teller effect iu the sample, Another broad attenuation peak was observed at around Tp-80 K. This anomaly is attributed to the phase separtion between the antiferromagnetic （AFM） and paramagnetic （PM） phases and gives a direct evidence for spin-phonon coupling in the compound. For the x=0.03 sample, both the minimum of sound velocity and attenuation peaks shift to a lower temperature. The results indicate that the charge ordering and CE-type AFM state in Nd0.5Ca0.5MnO3 are both partially suppressed by replacing Mn with A1.

Separation of arsenic from arsenic-antimony-bearing dust through selective oxidation-sulfidation roasting with CuS

The feasibility of a new method for separating arsenic from arsenic-antimony-bearing dusts using Cu S was put forward,in which Sb was transformed into Sb2O4 and Sb2S3 that stayed in the roasted calcine while As was volatilized in the form of As4O6.The factors such as roasting temperature and Cu S addition amount were studied using XRD,EPMA and SEM-EDS.Cu S has an active effect on the separation of arsenic due to the destruction of(Sb,As)2 O3 structures in the original dust and the simultaneous release of As in the form of As4O6.At a roasting temperature of 400°C and Cu S addition amount of 130%,the volatilization rates of arsenic and antimony reach 97.80 wt.%and 8.29 wt.%,respectively.Further,the high As volatile matter can be used to prepare ferric arsenate after it is oxidized,with this treatment rendering the vapor harmlessness.

Comparison of the Reynolds-averaged Turbulence Models on Single Phase Flow Simulation in Agitated Extraction Columns

The flow field of liquid phase (water) of agitated extraction columns is simulated with the help of computational fluid dynamics (CFD). Four kinds of Reynolds-averaged turbulence models, i.e. the standard k-ε model, the RNG (renormalization group) k-s model, the realizable k-ε model and the Reynolds stress model, are compared in detail in order to judge which is the best model in terms of the accuracy, less CPU time and memory required. The performance of the realizable k-s model is obviously improved by reducing the model constant from C2 = 1.90 to C2 = 1.61. It is concluded that the improved realizable k-e model is the optimal model.

Development of Combined Biological Technology for Treatment of High-strength Organic Wastewater and Results of Case Studies

Our study group has developed a unique combined ters from the industries of dyestuff, pharmaceutical, chemical biological technology to treat high-strength organic wastewaengineering and zymolysis by using the principles of anaerobic ecological niche and bio-phase separation. The study obtained five national invention patents and eight patent equipments. This technology contains four kernel processes - two-phase anaerobic-aerobic process, hydrolysis-acidification-oxidation process, UASBAF-oxidation process, and internal cycling-hydrolysis-oxidation process. Fifteen pilot projects were accomplished in the basins of Tai Lake, Huai River, Liao River and Songhua River, and their total capital investment reached 185.214 million Yuan （RMB）. Compared to conventional wastewater treatment technology, the innovative technology is more costeffective for high-strength organic wastewater treatment, can save capital investment by 15% - 30%, lessen land usage by 20% to 40% and decrease the operating cost by 10% to 25%. The operating cost of treatment per cubic meter industrial wastewater could be below 0.6 to 1.4 Yuan （RMB）.

Novel nanofiltration membranes with tunable permselectivity by polymer mediated phase separation in polyamide selective layer

Microstructure in selective layer has played a decisive role in permselectivity of nanofiltration(NF) membranes,and nanomaterials were well-known additives that had been applied to mediate the microstructure and permeability of polyamide NF membranes. However, nanoadditives generally displayed a poor dispersion in membranes or in fabrication process. To solve this problem, we showed an interesting concept that novel NF membranes with hybrid selective layer consisting of flexible polyisobutylene(PIB) and rigid polyamide could be fabricated from well-defined interfacial polymerization. The hydrophobic polymer mediated phase separation and microdomains formation in polyamide layer were found. The immiscibility between the rigid polyamide and flexible PIB as well as the resultant interface effect was interpreted as the reason for the polymer enhanced permselectivity, which was similar with the well-known thin film nanocomposite(TFN) membranes that nanoparticles incorporated contributed significantly to membrane permeability and rejection performance.Our results have demonstrated that novel NF membranes with enhanced performance can be prepared from immiscible polymers, which is a new area that has not been extensively studied before.

Effects of F127 on Properties of PVB/F127 Blend Hollow Fiber Membrane via Thermally Induced Phase Separation

Hydrophilic poly(vinyl butyral)(PVB) /Pluronic F127(F127) blend hollow fiber membranes were prepared via thermally induced phase separation(TIPS) ,and the effects of blend composition on the performance of hydrophilic PVB/F127 blend hollow fiber membrane were investigated.The addition of F127 to PVB/polyethylene glycol(PEG) system decreases the cloud point temperature,while the cloud point temperature increases slightly with the addition of F127 to 20%(by mass) PVB/F127/PEG200 system when the concentration of F127 is not higher than 5%(by mass) .Light scattering results show that the initial inter-phase periodic distance formed from the phase separation of 20%(by mass) PVB/F127/PEG200 system decreases with the addition of F127,so does the growth rate during cooling process.The blend hollow fiber membrane prepared at air-gap 5mm,of which the water permeability increases and the rejection changes little with the increase of F127 concentration.For the membrane prepared at zero air-gap,both water permeability and rejection of the PVB/F127 blend membrane are greater than those of PVB membrane,while the tensile strength changes little.Elementary analysis shows that most F127 in the polymer solution can firmly exist in the polymer matrix,increasing the hydrophilicity of the blend membrane prepared at air-gap of 5mm.

The beneficiation of tailing of coal preparation plant by heavymedium cyclone

Dense-medium cyclones have been used for beneficiation of fine particles of coal. In this study, the usability of cyclones in the beneficiation of tailings of a coal preparation plant was investigated. For this purpose, separation tests were conducted using spiral concentrator and heavy medium cyclones with the specific weight of medium 1.3-1.8 （g/cm^3） on different grading fractions of tailing in an industrial scale （the weight of tail sample was five tons）. Spiral concentrator was utilized to beneficiate particles smaller than 1 mm. In order to evaluate the efficiency of cyclones, sink and float experiments using a specific weight of 1.3, 1.5, 1.7 and 1.9 g/cm^3, were conducted on a pilot scale. Based on the obtained results, the recovery of floated materials in cyclones with the specific weight of 1.40, 1.47 and 1.55 g/cm^3 are 17.75%, 33.80%, and 50%, respectively. Also, the cut point （Pso）, which is the relative density at which particles report equally to the both products are 1.40, 1.67 and 1.86 g/cm^3. The probable errors of separation for defined specific weights for cyclones are 0.080, 0.085 and 0.030, respectively. Also, the coefficients of variation was calculated to be 0.20, 0.12 and 0.03. Finally, it could be said that the performance of a cyclone with a heavy medium of 1.40 g/cm^3 specific weight is desirable compared with other specific weights.

Probing Molecular Interactions in 1-Butyl-3-methylimidazolium Chloride-Water and 2,6-Dimethoxyphenol Mixtures Using Attenuated Total Reflection Infrared Spectroscopy

Molecular interactions of the ternary mixtures of 1-butyl-3-methylimidazolium chloride （[C4C1im]Cl）-water-2,6-dimethoxyphenol （2,6-DMP, a phenolic monomer lignin model compound） were investigated in comparison with the [C4C1im]Cl-water binary systems through attenuated total reflection infrared spectroscopy. Results indicated that the microstructures of water and [C4C1im]Cl changed with varying mole fraction of [C4C1im]Cl （xIL） from 0.01 to 1.0. This change was mainly attributed to the interactions of [C4C1im]Cl-water and the self-aggregation of [C4C1im]Cl through hydrogen bonding. The band shifts of C-H on imidazolium ring and the functional groups in 2,6-DMP indicated that the occurrence of intermolecular interactions by different mechanisms （i.e., hydrogen bonding or π-π stacking） resulted in 2,6-DMP dissolution. In the case of xIL=0.12, the slightly hydrogen-bonded water was fully destroyed and [C4C1im]Cl existed in the form of hydrated ion pairs. Interestingly, the maximum 2,6-DMP solubility （238.5 g/100 g） was achieved in this case. The interactions and microstructures of [C4C1im]Cl-water mixtures influenced the dissolution behavior of 2,6-DMP.

Painleve Nonstandard Truncation Expansion Solutions of Dynamics Equation ofDiblock Copolymer

Through Pickering's and extended Painleve nonstandard truncated expansionmethod, this paper solves the phase-separating dynamics equation of diblock copolymer, and obtainsvarious exact solutions. We discuss non-complex special solutions which can be made up of hyperbolicfunctions or elliptic functions.

Convection and Phase-Separation Behavior of Binary Mixture under Microwave Irradiation

When the temperature of a thin layer of a solution is vertically controlled, Rayleigh-Bemard convection is observed. When a binary isobutyric acid aqueous solution is used as the binary mixture, phase separation is simultaneously induced at the approximate critical solution temperature. In this study, these behaviors of phase separation and convection were observed under microwave irradiation. When the microwave power was higher, coalescence of fine droplets after the initial phase separation was accelerated and the coalescence size decreased. However, the solution became more unsteady because of smaller interfacial tension or greater heat generated by the radiation. Finally, in cases of higher microwave power, a steady convection pattern could not exist for a prolonged period because the water-rich phase was more active toward microwave irradiation, and the vertical temperature gradient became disordered.

HPLC fingerprint-oriented preparative separation of major flavonoids from safflower extract by preparative pressurized liquid chromatography

The aim of this study was to rapidly isolate the major effective flavanoids from the extract of safflower（Carthamus tinctorius） using ODS medium pressure liquid chromatography（MPLC） and semi-preparative HPLC, guided by a developed fingerprint. Twelve compounds were isolated and their structures were elucidated as kaempferol 3-O-β-D-rutinoside（1）, kaempferol 3-O-β-D-glucoside（2）, rutin（3）, quercetin 3-O-β-D-glucoside（4）, 6-hydroxykaempferol 3,6,7-tri-O-β-D-glucoside（5）, 6-hydroxykaempferol 3-O-β-D-glucoside（6）, 6-hydroxykaempferol 6,7-di-O-β-D-glucoside（7）, 6-hydroxykaempferol 3-O-β-Drutinoside（8）, 6-hydroxykaempferol 3,6-di-O-β-D-glucosyl 7-O-β-D-glucuronide（9）, isosafflomin C（10）, safflomin C（11） and hydroxysafflor yellow A（12） by spectroscopic analysis and comparing with the literature. Our results demonstrated that preparative pressurized liquid chromatography combined with HPLC fingerprint guide is an efficient tool to isolate the target compounds quickly.

Study of doping effect,phase separation and heterojunction in CMR manganites

Mixed-valence manganites have attracted considerable research focus in recent years not only because of the potential application of colossal magnetoresistance(CMR) in magnetic devices,but also because of many intriguing physical properties observed in these materials.Doping elements at A-site can alter the filling of 3d Mn band and the tolerance factor.Therefore the hole-and electron-doped CMR manganites exhibit a rich phase diagram.In addition,more theoretical and experimental results suggest that phase separation is a critical factor for the understanding of CMR phenomena.Recently,there is an increasing interest in the fabrication and investigation on manganite-based heterojunction,which demonstrated excellent rectifying property,large MR,and photovoltaic effect.

双塔变压精馏操作和节能浅析

双塔精馏广泛应用于均相共沸物的分离,分离效果可以达到99.5%以上。介绍了双塔变压精馏的原理以及在工业生产中的应用情况,并以四氢呋喃(THF)与水的分离为例,介绍了双塔精馏开车操作过程,影响双塔精馏效果的主要因素,造成产品不合格的原因。针对双塔变压精馏的使用,介绍了减少开车时间的经验。并对双塔精馏如何实现节能进行了介绍。

Photon retention in coherently excited nitrogen ions

Quantum coherence in quantum optics is an essential part of optical information processing and light manipulation.Alkali metal vapors,despite the numerous shortcomings,are traditionally used in quantum optics as a working medium due to convenient near-infrared excitation,strong dipole transitions and long-lived coherence.Here,we proposed and experimentally demonstrated photon retention and subsequent re-emittance with the quantum coherence in a system of coherently excited molecular nitrogen ions(N_(2)^(+))which are produced using a strong 800 nm femtosecond laser pulse.Such photon retention,facilitated by quantum coherence,keeps releasing directly-unmeasurable coherent photons for tens of picoseconds,but is able to be read out by a time-delayed femtosecond pulse centered at 1580 nm via two-photon resonant absorption,resulting in a strong radiation at 329.3 nm.We reveal a pivotal role of the excited-state population to transmit such extremely weak re-emitted photons in this system.This new finding unveils the nature of the coherent quantum control in N_(2)^(+)for the potential platform for optical information storage in the remote atmosphere,and facilitates further exploration of fundamental interactions in the quantum optical platform with strong-field ionized molecules.

Effects of surfactants on enzyme-containing reversed micellar system

With the development of colloid interface and enzyme technologies,enzyme-containing reversed micellar system has been receiving much attention in bioseparation and bioconversion. Because of its high efficiency,it has brought new opportunities for the development of molecular biotechnology. Reversed micelles represent nano-sized aqueous droplets stabilized by surfactant amphiphiles inside the bulk organic solvents. The entrapped enzymes have enhanced activities under those conditions as suited in the lipid bilayers of biological membranes. The fundamentals of enzyme-containing reversed micellar system are described in this paper,with special emphasis on the effects of surfactants varying in concentrations and structures. The latest study progress on the surfactants application in enzyme-containing reversed micelles is reviewed. The introduction of novel functional surfactants in micellar enzymology and their future development are also discussed.

GMP-quadruplex-based hydrogels stabilized by lanthanide ions

This work describes the gelation behaviors and properties of a biological molecule, guanosine 5′-monophosphate disodium salt(GMP), in the presence of trivalent lanthanide ions. Hydrogels composed of GMP-quadruplexes were prepared by adjusting p H,through which the protonation of phosphate group was controlled to tune the interactions between lanthanide ions and GMP.Within the p H region of 2–6, the electrostatic interaction between lanthanide ions and phosphate group is hindered and the cation-dipole interaction acts as the main driving force for the formation of G-quadruplexes. All the hydrogels were found consisting of three-dimensional network of the intertwining one-dimensional nanofibers formed by the stacking G-quartets induced by lanthanide ions. A significant fluorescence enhancement of thioflavin T(Th T), a fluorescent molecule, was found to be triggered by the G-quadruplex structures, for which the rotation of chromophoric groups on Th T molecules were prohibited due to the implant into the G-quadruplex structures.