Distribution of REE of Phosphate Concentrate in Wet-Phosphoric Acid Process

There exists the most important REE-bearing phosphorite deposit in Southwest of China. Due to the fact that the REE are present in the form of ions in the lattices of collophanite or carbonatfluorapatite, the REE can be enriched in phosphate concentrate by flotation method. The phosphate concentrate is the main raw materials to produce phosphoric acid, therefore, it is significant to further investigate the distribution rule of REE in wet process. In this paper, the single leaching and recycled leaching technology were carried out to investigate the effect of various parameter conditions on distribution of REE in products. The REE compositions of products were analyzed by Inductively Coupled Plasma Emission Mass Spectrometry (ICP-MS) method. It was found that the acidic value of leaching liquor was the main effect factor on the distribution of REE in products. In single leaching stage, P2O5 concentration of leaching liquor slightly varied from 8% to about 10% when the excessive coefficient of sulphuric acid ranged from 1.03 to 1.05, and the distribution proportions of ∑REO in phosphoric acid solution was lower than 40%. However, in recycled leaching process(the condition similar to practical wet process), with an increase of P2O5 concentration as well as the acidic value of leaching liquor, the distribution proportions of ∑REO in phosphoric acid solution could be decreased to 2.56%. That is to say that under the condition similar to practical wet process, more than 90% of REE of phosphate concentrate became precipitation entering into the phosphogypsum product. This investigation will provide valid reference for reasonably recovering or reserving REE in wet-phosphoric acid process.

Leaching Mechanism of the Spodumene Sulphuric Acid Process

Leaching mechanism of acid roasted ore in the spodumene sulphuric acid process was investigated. Experimental results of leaching rates along with variations of leaching temperature in the acidized and neutral leaching processes were reported. Applying ion exchange mechanism in acidized roasting and absorption entrainment mechanism at high temperature, leaching mechanism was discussed. A better explanation of experimental results was given.

Multi-objective Optimization of Industrial Purified Terephthalic Acid Oxidation Process

Multi-objective optimization of a purified terephthalic acid (PTA) oxidation unit is carried out in this paper by using a process modei that has been proved to describe industrial process quite well. The modei is a semi-empirical structured into two series ideal continuously stirred tank reactor (CSTR) models. The optimal objectives include maximizing the yield or inlet rate and minimizing the concentration of 4-carboxy-benzaldhyde, which is the main undesirable intermediate product in the reaction process. The multi-objective optimization algorithra applied in this study is non-dominated sorting genetic algorithm Ⅱ (NSGA-Ⅱ). The performance of NSGA-Ⅱ is further illustrated by application to the title process.

Production of Bamboo Fiber Reinforced Fibrillated Poly(Lactic Acid)(PLA) Material Obtained by a Papermaking Process

A devised beating process was applied, which enabled the formation of slurry consisting of uniformly dispersed fibrillated polylactic acid（PLA） fibers with bamboo fiber, and the polymer material was obtained by a conventional papermaking process. Owing to the fast dewatering time, good repeatability and the facility to manufacture on a large scale, this process was used. It was revealed that the beaten PLA fiber was overall in machinery extrusion by the results of optical microscope and scanning electron microscope（SEM） observations. The improvement in the tensile index, burst index, tear index and other mechanical properties was considered as a key benefit as a result of adding bamboo fiber.

Optimization of Fermentation Process for Hyaluronic Acid Production by Streptococcus zooepidemicus

Hyaluronic acid （HA） is a high molecular weight glycosaminoglycan consisting of alternating D-glucuronic acid and N-acetylglueasamine and plays ex- tremely important roles in many biological processes. In this study, we optimized fermentation process for the production of HA by Streptococcus zooepidemicus ATCC35246, including fermentation broth composition and various fermentation parameters. The experimental results showed that the optimal fermentation broth composition was： glucose 45 g/L, yeast extract 10 g/L, tryptone 12 g/L, KH2PO4 2 g/L, K2HPO4 . 3H20 2 g/L, MgSO4 · 7H2O 2 g/L, and （NH4 ）2SO4 0.4 g/L. The optimal parameters involved in fermentation was： liquid volume 20%, pH 6. 0, rotation speed 180 r/min, fermentation temperature 35 ℃, fermentation duration 18 h, CTAB concentration 25 mg/L. Under the optimized conditions, the yield of HA was 0. 305 g/L, which was dramatically improved by 43.87% compared to that of 0. 212 g/L before optimization.

Process mineralogy characteristics of acid leaching residue produced in low-temperature roasting-acid leaching pretreatment process of refractory gold concentrates

To provide a theoretical basis for a suitable process to extract gold from refractory gold concentrates, process mineralogy on the acid leaching residue of gold calcine was studied by chemical composition, X-ray diffraction, scanning electron microscopy-energy spectrum, and mineral dissociation analysis. The results showed that the acid leaching residue contained Au 68.22 g/t, Ag 92.71 g/t, Fe 0.44%, As 0.10%, and S 0.55%. Gold and silver minerals existed as native gold, argentite, and proustite. Quartz, the main gangue mineral, accounted for 78.33 wt/%. The dissociation degree analysis showed that the proportions of monomer and exposed gold in acid leaching residue were 96.66 wt%. The cyanidation results showed that the cyanide gold leaching rate of acid leaching residues was close to 100 wt%. However, the maximum cyanide gold leaching rate of gold calcine was only 85.31 wt%. This suggests that acid leaching can increase the gold dissolution rate in the cyanide process.

Research on Extraction Process of Gallic Acid from <i>Penthorum chinense</i>Pursh by Aqueous Ethanol

Penthorum chinense Pursh is rich in gallic acid, which has antioxidant, anti-inflammatory, anti-fungal and antitumor activities. In order to optimize their extraction conditions, various extraction parameters were chosen to identify their effects on gallic acid extraction. With extraction amount of gallic acid as index, based on single factor analysis, influence of solid/liquid ratio, ethanol concentration, fetch time and extraction temperature on extraction technology were investigated by orthogonal test. The optimization conditions for gallic acid extraction were determined as follows: ethanol concentration 60%, extraction time 2.5 h, temperature 90°C and solid/liquid ratio 1:30. The corresponding gallic acid content was 4.85%. This optimized extraction process was stable and feasible.

Extraction process of chlorogenic acid in flos lonicerae by enzymatic treatment

A new method of extracting chlorogenic acid from flos lonicerae, and treating the materials with enzyme before being extracted by ethanol is developed, and the optimum conditions are also investigated in detail. Three important factors, enzyme dosage, treatment time and treatment temperature are adapted to optimize the extraction process. The experimental results show that the extract yield of flos lonicerae and chlorogenic acid can be obviously increased by the cellulase treatment, 61.5 mg chlorogenic acid is obtained from 1.00 g flos lonicerae at most. The optimal temperature of enzymatic treatment is 40 50 ℃. Compared with the use of single cellulase, the combined treatment of cellulase and pectinase increase the extract yield obviously but fail to improve that of chlorogenic acid.

Application of advanced oxidation processes for removing salicylic acid from synthetic wastewaters

In this study,advanced oxidation processes(AOPs) such as anodic oxidation(AO),UV/H_2O_2 and Fenton processes(FP) were investigated for the degradation of salicylic acid(SA) in lab-scale experiments.Boron-doped diamond(BDD) film electrodes using Ta as substrates were employed for AO of SA.In the case of FP and UV/H_2O_2,most favorable experimental conditions were determined for each process and these were used for comparing with AO process.The study showed that the FP was the most effective process under aci...

Extraction Process and Content Determination of Caffeic Acid in Laggera alata from Different Production Areas of Guangxi

[Objectives] To establish a method for determining the content of Laggera alata( D. Don) Sch. Bip. Ex Oliv. using caffeic acid the target component,and to compare the content of caffeic acid in the medicinal materials of L. alata in different production areas of Guangxi.[Methods]The content was determined by Inertsil~ODS-3 chromatographic column C_(18)( 4. 60 mm × 250 mm,5 μm,mobile phase: acetonitrile-0. 1% phosphoric acid( 22∶ 78),detection wavelength: 320 nm,flow rate: 1. 0 m L/min,column temperature: 30℃,and injection volume: 10 μL. [Results] The caffeic acid showed a good linear relationship in the range of injection volume of 0. 025 92-0. 259 2 μg( R =0. 999 5). The average recovery rate was 98. 33%( RSD = 1. 85%). L. alata in different production areas of Guangxi contained the caffeic acid,and there was a great difference in the caffeic acid. L. alata in Baise had the highest content of caffeic acid,while that in Guilin had the lowest content of caffeic acid. [Conclusions]This method can accurately determine the content of caffeic acid and is expected provide a scientific basis for the development and utilization of herbal medicine L. alata.

Degradation of 2,4-dichlorophenoxyacetic acid in water by ozonehydrogen peroxide process

This study reports an investigation into the degradation of 2,4-dichlorophenoxyacetic acid in bubble contactor column by O2/H2O2 process, which is widely used as a principal advanced oxidation process. The degradation of 2,4-dichlorophenoxyacetic acid was studied under different H202/O3 molar ratio and pH value. Meanwhile, TOC removal was investigated both in distilled water and tap water. The influences of ozone transfer and consumed hydrogen peroxide were also discussed. The degradation products and oxidation intermediates were identified by GC-MS and LC-MS. A possible reaction mechanism was thus proposed.

Production process for ursolic acid

Production of ursolic acid, the anti-hepatitis effective composition from natural plant,Sambucus chinensis Lindl.was carried out and the scale-up preparation technology was studied.Extraction of the herb Sambucus chinensis Lindl.was extracted in reflux with 7 volume times of refluxing ethanol at 80℃ for 1 h for two times.The extract was purified with a selt-made specific impurity remover “YCXY-1” to yield ursolic acid of high purity.A new “Extraction/Gelation” technology for the production of ursolic acid was developed. The specific impurity remover “YCXY-1” showed high effectiveness in purification. The purity of the mass-produced ursolic acid was up to 99.8%. The chemical structure of the product was confirmed by the physicochemical constants and spectroscopic identification. The production of high-purity ursolic acid was optimized with natural plant as raw material and with only ethanol as extracting solvent. The difficulties such as isolation and impurity removal were addressed effectively. The novel technology is reasonable, convenient, practical, low-cost, high-yield, suitable for mass production.

基于靶向代谢组学研究苍术麸炒前后干预脾虚大鼠氨基酸水平变化的影响

目的研究采用靶向代谢组学方法,观察苍术麸炒前后对脾虚大鼠血清氨基酸水平的变化,探讨苍术炮制机制。方法72只大鼠随机分成正常组、模型组、低剂量生苍术组(生低组)、中剂量生苍术组(生中组)、高剂量生苍术组(生高组)、低剂量麸炒苍术组(麸炒低组)、中剂量麸炒苍术组(麸炒中组)和高剂量麸炒苍术组(麸炒高组),共8组,每组9只。除正常组外,模型组通过过度疲劳、苦寒泻下和饮食不节法造模。对各组大鼠采用酶联免疫吸附测定(Enzyme Linked Immunosorbent Assay,ELISA)方法测定颌下腺中水通道蛋白3(Aquaporin-3,AQP-3)、水通道蛋白4(AQP-4)、水通道蛋白5(AQP-5)、水通道蛋白8(AQP-8)的含量,结肠中水通道蛋白1(AQP-1)、水通道蛋白2(AQP-2)、水通道蛋白9(AQP-9)、紧密连接蛋白1(zonula occludes protein-1,ZO-1)的含量。对生中组和麸炒中组采用超高效液相色谱-三重四极杆质谱(Ultra high performance liquid chromatography-triple quadrupole tandem mass spectrometry,UH-PLC-MS/MS)检测血清中24种氨基酸水平的变化。结果与正常组比较,模型组中颌下腺AQP-3、AQP-4、AQP-5、AQP-8的含量显著降低(P<0.05);模型组中结肠AQP-1和AQP-2的含量显著升高(P<0.05),AQP-9和ZO-1的含量显著降低(P<0.05)。生苍术和麸炒苍术对上述指标均有调节作用。经进一步同等剂量的生苍术和麸炒苍术相比,麸炒中组使上述指标含量升高更明显。与正常组比较,模型组血清中L-缬氨酸等4种物质的水平显著升高(P<0.05),L-酪氨酸等11种物质的水平均显著降低(P<0.05)。经进一步比较,麸炒苍术对上述指标调节效果优于生苍术。靶向代谢通路分析表明,这些差异代谢物主要与精氨酸和脯氨酸代谢、氨酰tRNA生物合成、甘氨酸、丝氨酸和苏氨酸代谢、乙醛酸和二羧酸代谢通路有关。结论苍术炮制后的增效机制可能与对脾虚大鼠血清中氨基酸调节有关。

Effects of Different Processing Methods on Chlorogenic Acid Content in Fructus Gardeniae

[ Objective] This study aimed to compare the effects of different processing methods on the content of chlorogenie acid in Fructus Garden/ae. [ Method] The chromatographic separation was performed on an Inersil ODS-2 C18 column （250 mm× 4.6 mm, 5 μm） with acetonitrile -0. 1% acetic acid solution （ 12： 88, V/V） as the mobile phase under conditions of tlow rate 1.0 mb/min, detection wavelength 327 ran, column temperature 25℃. [ Result J With a range of 0.42-2.52 μg/i.d, ehlorogenic acid concentration exhibited a good linear relationship with peak area （n =6, R =0. 999 9）. The average recovery rate was 100. 83%, RSD was 1.30%. [Conclusion] The established method is eonveniem, rapid and accurate with good repeatability, which can be used to effectively control the quality of different orocessed oroduets of Fructus C.ardeniae.

Microwave enhanced chemical reduction process for nitrite-containing wastewater treatment using sulfaminic acid

High-concentration nitrite-containing wastewater that presents extreme toxicity to human health and organisms is difficult to be treated using traditional biological process. In this study, a novel microwave-enhanced chemical reduction process （MECRP） using sulfarninic acid （SA） was proposed as a new manner to treat such type of wastewater. Based on lab-scale experiments, it was shown that 75%-80% nitrite （NO2-） could be removed within time as short as 4 min under 50 W microwave irradiation in pH range 5-10 when molar ratio of SA to nitrite （SA/NO2-） was 0.8. Pilot-scale investigations demonstrated that MECRP was able to achieve nitrite and chemical oxygen demand （COD） removal with efficiency up to 80% and 20%, respectively under operating conditions of SA concentration 80 kg/m3, SA/NO2- ratio 0.8, microwave power 3.4 kW, and stirring time 3 min. Five-day biological oxygen demand （BODs）/COD value of treated effluent after MECRP was increased from 0.05 to 0.36 （by 620%）, which clearly suggested a considerable improvement of biodegradability for subsequent biological treatment. This study provided a demonstration of using microwave irradiation to enhance reaction between SA and nitrite in a short time, in which nitrite in wastewater was completely converted into nitrogen gas without leaving any sludge and secondary pollutants.

Effect of Storage Conditions on the Sensory Quality, Colour and Texture of Fresh-Cut Minimally Processed Cabbage with the Addition of Ascorbic Acid, Citric Acid and Calcium Chloride

The aim of this study was to investigate the effect of storage conditions on the sensory quality, colour and texture of fresh-cut cabbage during the addition of ascorbic acid, citric acid and calcium chloride. Ascorbic acid maintained the overall quality for 14 days at 0℃ and 7 days at 5℃;no difference, however, was observed regarding browning of cut surface compared to the control sample at both storage temperatures. Calcium chloride maintained the overall quality and cut surface browning for 14 days at both storage temperatures. It was also found that citric acid 1% can be used for minimally processed cabbage. Soaking with citric acid helped retain the color and increased the overall acceptance and organoleptic quality of fresh cut cabbage;it reduced browning of the cut surface and protected against formation of black specks. Citric acid treatment combined with low temperature storage (0℃) prolonged the shelf life of minimally processed cabbage for 22 days, time sufficient for acceptable marketing of the product. The lightness of minimally processed cabbage decreased linearly from 70.94 ± 6 to 63.8 ± 8.5 - 61.3 ± 8 units for the chemical treatments during 22 days of storage at 0℃. Hue angle values during storage time were also significantly influenced by chemical treatments mainly at 0℃.

不同热处理条件下橡胶木淀粉含量与抗蠹虫性能关系研究

为克服橡胶木易发生蠹虫危害的缺陷,采用不同热处理温度(90、120、150℃和180℃)和不同热处理时间(2、4 h和6 h)对橡胶木进行热处理,利用分光光度计考察不同温度和时间条件下热处理橡胶木中的淀粉含量变化,并分析蠹虫对橡胶木的蛀蚀程度与淀粉含量之间的关系。结果表明:热处理温度和处理时间对橡胶木中的淀粉含量有显著影响,且随着热处理温度的升高和热处理时间的延长,淀粉含量逐渐下降,从12.79%降至1.25%。在橡胶木抗蠹虫试验中,热改性处理后橡胶木的抗蠹虫效果均优于对照材,且橡胶木淀粉含量越低,其抗蠹虫效果越好。在实际生产过程中,在120℃下处理6 h为生产热处理橡胶木的优化条件,既能刚好维持橡胶木抗蠹虫的最低要求,也能降低热处理过程中木材强度的损失。

A new acid pickling process for copper alloys

The cleaning process of removing oxides on the surface of copper alloy sheetswas investigated systematically. Through optimizing, a perfect process was selected that is fit forremoving oxides on the surface. By acid pickling, all kinds of copper oxides are removedcompletely, furthermore, no poisonous gases are given out and a smooth and clean surface of copperalloys is obtained. At present, the process is applied successfully in the copper-processingindustry.

天然鳞片石墨提纯研究进展

天然鳞片石墨是一种战略资源,对国民经济发展及现代化建设具有重要作用。石墨材料因其具有导电、耐热、抗腐蚀、韧性好、润滑性能好等优异性能,被广泛应用于密封、铸造、防火材料、导电材料等传统工业领域,在新能源、电子信息技术、高端装备技术等新兴领域也具有潜在的应用价值,被誉为“工业黑金”。虽然我国有着丰富的石墨资源,但由于石墨提纯技术落后,石墨深加工产品与国外仍有一定差距。石墨材料纯度越高其应用价值越高,因此,研究高效、节能的石墨提纯技术对我国石墨产业的发展具有十分重要的意义。目前,常用的石墨提纯方法可分为物理提纯法和化学提纯法,其中,物理提纯法包括浮选法、高温法,化学提纯法包括氢氟酸法、酸碱法和氯化焙烧法。分析对比了这几种提纯方法的原理、优点及存在的问题。未来的研究方向主要集中在对单一提纯方法的工艺流程、提纯设备的优化,多种方法联合使用,以及新方法的开发及应用等方面。

A Gold Electrode QCM Study on the Self-Assembling Process of Thioglycollic Acid in Aqueous Solution

In this letter, the self-assembling process of thioglycollic acid on gold in aqueous solutions was studied by QCM technique. Frequency information suggests bilayer or multilayer adsorbate formation in 0.5 mol/L HCl solution but only monolayer one in 0.5 mol/L KOH solution. This phenomenon is explained by hydrogen bond effect.