pH混合调整剂对磷矿石浮选的影响

为了改善低品位磷矿的正浮选性能,以某磷矿为试验样品进行了以碳酸钠、碳酸氢钠和氢氧化钠为组合pH调整剂的浮选试验。结果表明,以碳酸钠和氢氧化钠为组合pH调整剂时,浮选效果偏差,而以碳酸钠、氢氧化钠和碳酸氢钠为组合pH调整剂时,可以得到较好的浮选效果。本文采用单纯型点阵设计进行了优化研究,以3种pH调整剂的用量为试验因素,在原矿P_2O_5品位为5.59%,碳酸钠、碳酸氢钠与氢氧化钠的组合比例为2∶1∶1时,经正浮选(1次粗选)试验,获得了P_2O_5品位为28.81%、P_2O_5回收率为86.50%的磷精矿,实现了磷灰石矿物与脉石矿物的有效分离。     

预处理玉米芯对活性翠蓝的吸附性能研究

研究了预处理玉米芯对活性翠蓝K-GL染料的吸附性能,考察了溶液的pH值、初始质量浓度、时间和温度对吸附性能的影响。结果表明,预处理玉米芯对活性翠蓝K-GL废水吸附处理的最佳处理条件为：pH值为1．0,吸附时间为22h,初始质量浓度为1100．0mg／L、温度为60℃。在此条件下,实现了以废治废、变废为宝的目的。     

苯并噁二唑类荧光探针的合成及对pH的检测

以4-硝基苯并噁二唑氯和1-苄基哌嗪为原料,通过亲核取代,设计合成了一种新型苯并噁二唑类化合物,其结构用~1H MNR进行了表征。利用荧光光谱、紫外光谱测试了该化合物对pH响应的光谱行为,结果表明,该化合物与质子结合后,通过PET过程可以实现对pH的检测。在3～6之间,荧光强度与pH之间具有较好的线性关系,同时该化合物能够高选择性、高灵敏性的检测溶液中的pH。     

沉淀法生产白炭黑过程中pH值检测方法的改进

在沉淀法生产白炭黑的过程中通过pH值来控制产品的质量,同时也根据pH值实现自动生产。由于沉淀法生产过程中反应物为糊状物、反应环境为强酸强碱,pH值的检测误差较大且传感器寿命较短。根据沉淀法生产过程详细介绍了pH值检测的硬件和软件设计以及pH传感器的维护。实际应用表明,其速度和精度完全达到了工艺上对pH值的控制要求。     

电镀酸锡废水中不同金属离子的分离工艺

利用各种金属离子形成氢氧化物沉淀时pH的不同,从而实现电镀酸锡废水中各金属离子的分离与回收。原废水的pH为0.45,其中含锡137.3mg/L、Ni46.1mg/L、Fe11.4mg/L、Co8.6mg/L。先用10%的氢氧化钠溶液调节废水的pH为4.7,废水中的锡元素形成氢氧化亚锡沉淀;分离锡元素后的废水用10%的双氧水把其中的亚铁完全氧化成三价铁,再调节废水的pH至4.1,以除去铁元素;在分离了铁元素的废水中加入10%的次氯酸钠溶液,把其中的二价钴完全转化成三价钴,再调节废水pH为5~6,以分离钴元素;调节除钴后废水的pH为9.5沉淀其中的镍元素。     

支撑液膜法制备头孢氨苄的研究

建立一个三相体系,实现对头孢氨苄的合成与分离。对支撑液膜及其传质机理进行了简要介绍。实验中,以Isopar L为萃取剂,甲基三辛基氯化铵(Aliquat 336)为载体,1-癸醇为载体助溶剂。萃取部分考察了进料相头孢氨苄的浓度、进料液pH、进料相和有机相体积比对萃取率的影响。反萃部分考察了反萃液pH对反萃率的影响,对比了几种反萃液的反萃效果,最终选择pH=9.0的D-苯甘氨酸甲酯盐酸盐(PGME)溶液作为反萃液。选择进料头孢氨苄浓度为20 mmol/L,进料液pH为9.0,进料相与有机相体积比为1∶1进行实验,得到头孢氨苄的最终收率为58.43%。     

富油微藻培养过程中pH的分阶段调节路径

富油微藻的培养是以获得较高总脂含量为目的,培养过程中提高生物质积累量和提高细胞内油脂含量同等重要。依据微藻生物量积累和油脂积累对培养基pH的要求不同,提出了富油微藻培养过程中pH的分阶段调节路径,通过分阶段主动控制培养基的pH来实现分阶段分别提高微藻生物质积累量和油脂含量的目的。微藻培养过程中pH分阶段调节路径的实施,可以提高微藻生物柴油产业的总产油量,降低微藻生物柴油的生产成本。     

脱硫辅塔浆液pH值测量方法研究

石灰石/石膏湿法烟气脱硫(WFGD)系统浆液pH值与系统脱硫性能、石灰石溶解、亚硫酸盐氧化、石膏结晶具有密切关系,为基于浆液pH值的实时特性实现脱硫系统的优化运行,必须实现浆液pH值的准确测量。在综述当前脱硫塔pH值测量方法的基础上,提出了一种新型的脱硫辅塔浆液pH值测量装置,可以真实测量辅塔浆液pH值及pH值变化,真实反映出吸收塔与辅塔pH值分区效果,为超低排放后优化运行提供依据。     

pH和有机配体对Cu-Pb复合污染土壤中Cu的解吸行为的影响

以黄棕壤为供试土壤,研究了pH对Cu-Pb复合污染土壤中Cu的解吸行为的影响。实验结果表明,无论以EDTA还是以C IT为萃取剂,pH值都会对Cu的解吸情况产生重要影响。当解吸液pH值为4.0时,Cu的解吸量最小;Cu的解吸率在各个pH下的大小顺序大致为:pH 5.6的>pH 3.0的>pH 4.0的。     

综合电镀废水处理技术的实验研究

以深圳某大型电镀工业园产生的综合电镀废水为研究对象,对其处理方法进行了探索,确定了酸化-氧化破络反应及氢氧化物和硫化物共沉淀的处理方法;通过实验选择漂水为最佳破络剂,最佳破络操作参数为漂水用量1.2mL/L,反应pH为2.3,反应时间2.0h,在此基础上调节pH并加入硫化钠即可实现电镀废水的达标排放,克服了传统电镀废水处理工艺的不足。     

Preparation of Glycinin and β-Conglycinin from High-Sucrose/Low-Stachyose Soybeans

A new soybean line, known as high-sucrose/low-stachyose (HS/LS) soybeans, has been developed having elevated sucrose content and reduced content of flatus-causing oligosaccharides, especially stachyose. There is also increased interest in understanding the health benefits, functional properties and potential applications for the two major storage proteins of soybeans, glycinin and β-conglycinin. We evaluated the protein fractionation behavior of a HS/LS soybean line and compared it to normal soybeans when using the three-step Wu procedure, which employs SO₂, NaCl and precipitations at pH 6.4 and 4.8 and a new two-step Deak procedure, which employs SO₂, CaCl₂ and precipitations at pH 6.4 and 4.8. Both soybean variety and fractionation procedure significantly affected fraction yields, purities and functional properties. The Wu procedure gave glycinin- and β-conglycinin-rich fractions with 100% purities and high yields of solids (15.4%) and protein (31.7%) from HS/LS soy flour, which were significantly higher than the purities and yields achieved with normal soybeans. The Deak procedure was less efficient in fractionating proteins from HS/LS soybeans than from normal soybeans, producing protein fractions from HS/LS soybeans with purities ranging from 71 to 80%. The Deak procedures yielded products with unique solubilities, surface hydrophobicities, and emulsification and foaming properties.     

Gelcasting of alumina-chitosan beads

Several papers have reported the advantageous combination of chitosan and ceramic particles for such applications as biomimetic scaffolds, membranes, pollution remediation and gelcasting complex shapes. This work presents a novel gelcasting consolidation mechanism, based on the effects of pH changes on chitosan solubility and zeta potential of alumina particles. Unlike other chitosan-based gelcasting methods, it employs a small content of organic material (lower than 3 wt%) and does not require crosslinking agents (such as glutaraldehyde). With this new method alumina beads with 0.5-1 mm diameter could be produced, whose porosity and specific surface area could be tuned for various applications.     

Hemoglobin Extraction Using Cosurfactant-Free Nonionic Microemulsions

ABSTRACT

Oil-continuous microemulsions provide an effective medium as a liquid membrane for extraction of proteins due to high solubilization and low miscibility in aqueous feed. Unlike the use of reverse micelles, this new method employs a preformulated cosurfactant-free nonionic microemulsion of high water content. The use of nonionic microemulsions for hemoglobin extraction demonstrates the potential for effective separation of proteins, amino acids, and other biochemicals. The extraction can be controlled by adjusting pH and microemulsion composition. It is enhanced by the addition of an appropriate liquid ion exchanger. The extraction results cannot be explained only in terms of ionic interactions.     

Protection of lyocell against fibrillation. Part 2: Application of 4,6-(p-β-sulphatoethylsulphonyl)anilino-1,3,5-triazin-2(1H)-one to lyocell by an exhaust process

An exhaust application method for 4,6-( p - β -sulphatoethylsulphonyl)anilino-1,3,5-triazin-2(1 H )-one to dried lyocell fibre has been developed. The procedure employs a temperature gradient technique with all of the salt and alkali present at the start. This method gives consistent wet abrasion resistance values with a standard deviation only marginally inferior to Tencel A100. Subsequent dyeing of lyocell fibres, in turn with two reactive dyes, gave build-up profiles indistinguishable from untreated fibre. The lyocell–agent bonding was stable to high temperature polyester dyeing conditions at pH 6, but unexpectedly showed some instability (as evidenced by a fall in wet abrasion resistance values) when subjected to base-catalysed reactive dyeing conditions.     

Rubidium and Cesium Ion Adsorption by a Potassium Titanium Silicate-Calcium Alginate Composite Adsorbent

In this work, a composite spherical adsorbent, which employs potassium titanium silicate as an adsorption active component, and calcium alginate as a carrier, was successfully prepared. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were used to characterize the adsorbent. The kinetics and thermodynamics of rubidium and cesium ions adsorption were investigated comprehensively, by considering the effects of initial concentration, temperature, solution pH, and coexisting NaCl. According to the determination coefficients, the pseudo second-order kinetic model provided an impressive and comparable correlation, and the second-order rate constant and the initial adsorption rate increase with increasing temperature. In general, the equilibrium adsorption amount increases with the increasing initial metal ion concentration, but decreases with increasing coexisting NaCl. The adsorption capacity keeps constant in the pH value range 3-12 and slightly fades when the temperature increases from 25 to 55°C. Under similar conditions, rubidium and cesium show the similar adsorption amount. The adsorbent has a fast adsorption rate and an adsorption capacity of about 1.55 mmol g^?1 for rubidium and 1.47 mmol g^?1 for cesium when the initial metal ion concentration is 0.10 mol L^?1. The composite adsorbent is effective for the adsorption of rubidium or cesium ions from simulated brines.     

基于ZigBee与Android平台的功图量油系统

针对油田边远井不便使用原有功图量油系统的情况设计手持自动化量油系统。该系统采用ZigBee芯片JN5139、加速度传感器ADXL202和载荷传感器INA122U作为网络平台,设计了数据采集处理系统;采用Android 2.2平台开发数据采集、传输软件。将ZigBee网络以及Android 2.2平台的GPRS与蓝牙模块融合应用于系统无线传输方案的设计中,实现了功图量油系统的数据采集和远程数据传输。     

A combined experimental-numerical study of the compaction behavior of NaCl

The compaction behavior of NaCl as a model substance is investigated by an integrated experimental and computational approach. The method for characterization of this granular material employs convenient experiments: load-displacement measurements of compaction; measurements of strain on outer circumference of an elastic tubular die; load on bottom and top of the powder compact, as well as compressive strength tests. Related equations for identification of material parameters are derived and are used to characterize powder behavior and powder-die friction. Subsequently, these material parameters are used in simulations with the Drucker-Prager-Cap (DPC) model. For the verification of the computations density distributions are determined based on micro X-ray computer tomography. Good agreement between the spatial density distributions from measurements and simulations is obtained. Restrictions of computer tomography in powder compaction applications are specified. While the study employs NaCl as a model substance, the approach is applicable to a wider array of granular substances.     

Hydrometallurgy Wastewater Split-Up by Fluidized-Bed Ion-Exchange Continuous Equipment

ABSTRACT

A proposed operation of a semicontinuous fluidized-bed ion-exchange system was studied. The system splits a liquid current into two currents, one being more concentrated and the other more depleted. This operating technique has been used to split up a mixture of alkaline ions (Na⁺, K⁺) using a strongly acidic resin. The equipment operates simultaneously in two multistage columns, one for loading and the other for elution of the resin. The experimetal testing system employs a hydrometallurgy wastewater containing cobalt and copper as heavy metallic ions, and the resin used was of the chelating iminodiacetic type, Lewatit TP-207. At cyclic steady state, the equipment can split up the wastewater, producing an effluent concentrated in cobalt in the outlet stream of the loading column, and a concentrated stream of copper in the effluent of the elution column. The hydrodynamics and approach to the stationary state of the system were analyzed, and the selective recovery of metals was subsequently tested experimentally. This behavior presents certain similarities with a parametric pumping operation of the system, with the two columns operating at different pH values or temperatures.     

聚氨酯-环氧树脂复合乳液研究进展

综述了聚氨酯和环氧树脂相互改性乳液的研究进展。聚氨酯改性环氧树脂乳液的方法包括物理共混法、化学共聚的单组分法与双组分法以及聚氨酯固化剂改性法,改性乳液涂膜的力学性能和柔韧性明显提高。环氧树脂改性聚氨酯乳液的方法包括物理共混法和化学共聚的直接改性法、间接改性法,改性乳液的固含量提高,涂膜的硬度、耐水性、耐化学品性增强。     

A Novel Method For Fabricating Cr-Doped Alpha-Al<Subscript>2</Subscript>O<Subscript>3</Subscript> Nanoparticles: Green Approach To Nanotechnology

The aim of this work was to produce Cr-doped alpha-alumina nanoparticles using a modified sol–gel method that employs the complexation capacity of natural organic matter (NOM). For this synthesis, the initial pH of the sol was adjusted to 4.0, and final calcination of the xerogel was performed at 1100?°C for 4 h. XRD and FTIR analyses confirmed that the hexagonal α-Al₂O₃ phase was produced under these conditions. Chromaticity analyses revealed that more intense pink colors were obtained for the samples with higher Cr concentrations. XANES measurements showed that the oxidation state of chromium in the alumina matrix was strongly dependent on the dopant concentration and that it was possible to produce samples free from Cr(VI). The photo- and radioluminescence spectra of the nanoparticles were found to be sensitive to the dopant concentration. All these findings demonstrated that the synthesis procedure using NOM could provide considerable environmental, technological, and economic benefits.