Guayule seedling response to nitrogen fertilizers

Slow growth and high seedling mortality limit direct seeding establishment of guayule (Parthenium argentatum G.). This study was conducted to assess seedling growth enhancement by the addition of different rates and forms of N fertilizers and Ca salts. Experiments were conducted in a greenhouse with cultivar 593 under both surface and subirrigated conditions using water low in salts (salinity of 0.8 dSm^–1, SAR of 5.0 and 10 mg Ca L^–1). Under surface-irrigated conditions, seedling height and fresh plant weight increased with N application to the irrigation water to 70 mg L^–1. The best seedling growth was observed when (NH₄)₂SO₄ was added in combination with CaCl₂ or CaSO₄. Progressively less growth was observed by addition of (NH₄)₂SO₄ alone, CO(NH₂)₂ plus CaSO₄, CO(NH₂)₂ alone and Ca(NO₃)₂. When seedlings were subirrigated, however, the best growth was observed with Ca(NO₃)₂. Intermediate growth was obtained with (NH₄)₂SO₄ plus CaSO₄ and lowest growth rates with (NH₄)₂SO₄ alone. These differential responses may be explained by the differences in leaching and volatile characteristics of the N forms. Growth enhancement from N and Ca additions increased with time with significant increases 45 days after seeding. Nitrogen application with Ca may be effective amendment in promoting subsequent growth of direct seeded guayule.     

锌精矿常压浸出与加压浸出工艺比较

比较了常压浸出与加压浸出两种工艺的机理、流程、技术经济指标、投资以及存在的问题。试验和生产数据表明,加压浸出在技术上和工艺上都更具有吸引力。     

含铜和镍电镀污泥还原氨浸工艺及反应动力学分析

采用还原氨浸工艺实现电镀污泥中铜、镍的浸出。在20%(质量分数)氨水+0.3 mol/L (NH₄)₂CO₃+0.4 mol/L Na₂SO₃的浸出体系中,当固液比为1∶15,在70℃下浸出3h,铜、镍的浸出率别为95.84%和90.12%。反应动力学分析表明,氨-碳酸铵-亚硫酸钠体系浸出电镀污泥中铜、镍受界面传质和固体膜层扩散共同控制。     

Computational modelling of unsaturated flow of liquid in heap leaching—using the results of column tests to calibrate the model

Unsaturated flow of liquid in a bed of uniform and spherical ore particles is studied numerically and experimentally. An unsteady and two-dimensional model is developed based on the mass conservation equations of liquid phase in the bed and in the particles. The model equations are solved using a fully implicit finite difference method giving the distribution of the degree of saturation in the particles and in the bed and the vertical velocity of flow in the bed, as well as, the effect of periodic infiltration on the above distributions. To calibrate the computational model, several column tests are performed using periodic infiltration of water on 40 cm high columns composed of ore having particles smaller than 25 mm. The numerical analysis shows that (a) the results obtained from numerical modelling under the same operating conditions as used for column tests, are in good agreement with those from experimental procedure, (b) the degree of saturation of the bed and the time required to reach steady state conditions depend on the inflow of water and intrinsic permeability of the bed and (c) the velocity fluctuations and the fluctuations of the degree of saturation in the bed depend on the inflow of water, period of infiltration, height and intrinsic permeability of the bed.     

德兴铜矿废石排放与堆浸筑堆相结合的探讨

本文阐述了德兴铜矿祝家废石场为满足废石排放和堆浸喷淋的双重工艺要求 ,提出了具体的措施和有利于二者的新布局构思     

毛洋头铀矿床淋浸液萃取分离铀钼工艺技术研究

毛洋头铀矿床淋浸液中的铀、钼能同时被三脂肪胺萃取,负载有机相经分别采用酸性溶液反萃取铀、碱性溶液反萃取钼的二步反萃取法,铀和钼达到了有效分离。     

氯化铵溶液中还原浸出海洋锰结核

采用亚硫酸钠作还原剂对氯化铵溶液中海洋锰结核的浸出行为进行研究，探讨Ｎａ２ＳＯ３加入量、ＮＨ４Ｃｌ浓度及初始ｐＨ值、浸出温度和时间等对锰结核中铜、镍、钴、锰、铁浸出率的影响。结果表明５．０ｍｏｌ／ＬＮＨ４Ｃｌ溶液中，初始ｐＨ值约５．０及８０℃、１８０ｍｉｎ，锰结核与Ｎａ２ＳＯ３等量加入时，铜、镍、钴、锰的浸出率分别为８８．５６％、９６．１４％、７８．５７％、３５．２％，铁几乎未被浸出。而在同样的条件下，控制浸出过程的ｐＨ值４．０左右，１２０ｍｉｎ后铜、镍、钴、锰、铁的浸出率分别为９０．２１％、９８．８０％、９１．４３％、９８．１１％、２０．１３％。     

一种保健型银杏茶饮料加工技术的初步研究

针对银杏茶冲泡饮用时黄酮类物质、苦内酯等物质浸出率比较低的问题,提出了一种新的银杏茶饮料加工技术,设计了一种新的加工工艺,使银杏叶中黄酮类物质的浸出率高迭82.3%～86.5%,大大提高了银杏茶饮料的保健功效.     

Preparation and characterization of porous polyester fibres by salt leaching method

Porous polyester fibres with cotton-like dull characteristics were produced by salt leaching method. Polyester was synthesized in the presence of common salt. Fibres containing submicron size salt particles (0.5–1%) were prepared by melt spinning. The fibres were washed in hot water to remove the salt particles creating small craters of size 50–1000?nm. Partially oriented yarn (POY) and fully drawn yarn (FDY) were produced. POY samples were textured to produce polyester textured yarn containing salt particles. The influence of salt particles on polymer crystallization was investigated and found that the presence of salt significantly influences the rate of crystallization. The gloss values of porous FDYs were compared with standard semi-dull polyester yarns of same denier. The light scattering behaviour of the yarn has been enhanced due to porosity. This resulted in a fibre with better dullness characteristics. The light reflectance of porous yarn is lower in the 400–700?nm region compared to control FDY samples. The dyeability of the porous fibre was better than non-porous counterpart.     

嗜酸氧化亚铁硫杆菌浸取印刷线路板中铜的多点添加策略

考察了嗜酸氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans)对废弃印刷电路板(PCBs)中铜回收的影响.由于PCBs添加时间和浓度显著影响菌体生长及铜浸取率,因而通过多点添加PCBs的策略促进铜浸取并减少对细胞生长的抑制.结果表明,PCBs添加量为18 g/L(4 g/L于48 h,6 g/L于96 h和8 g/L于144 h)时,经过240 h培养,铜浸取率达80%,说明该策略有效和可行.