Effect of organic amine alkali and inorganic alkali on benzotriazole removal during post Cu-CMP cleaning

Benzotriazole(BTA), an anticorrosion agent of slurry, is the main organic pollutant remaining after CMP of multilayer copper wiring, and also the main removal object of post CMP cleaning. The adsorption of BTA onto the copper could form a dense Cu-BTA film, which makes the copper surface strongly passivated. According to this characteristic, quantitative analysis of BTA residue after cleaning is carried out by contact angle measurement and electrochemical measurement in this paper. A scanning electron microscope(SEM) with EDX was used to observe and analyze the BTA shape and elements. The efficiencies of organic alkali and inorganic alkali on the removal of BTA were studied. The corresponding reaction mechanism was also analyzed. The results show that the adsorption structure of Cu(I)-BTA cannot be destroyed in an alkaline environment with a pH less than 10; the effect of BTA removal by inorganic alkali is worse than that of the organic amine alkali with the coordination structure under the same pH environment; the FA/O Ⅱ chelating agent with the fraction of 200 ppm can effectively remove BTA residue on the surface of copper wafer.

THE SYNERGISTIC INHIBITION STUDIES OF SEVERAL AMINES AND CHLORIDE ION ON IRON IN THE ACIDIC PERCHLORIDE SOLUTIONS

The effect of chloride ion on the corrosion inhibition of iron caused by dencylamine(DA), dipentylamine(DDA) and dodecylamine(DPA) has been investigated by measuring the inhibitory coefficients for the anodic and cathodic processes at corrosion potential. It has been shown that the major synergistic inhibition effects between amines and chloride ions occur in the cathodic process, very weak in the anodic process. The anodic inhibition mechanism follows the competing adsorptive model, while the cathodic inhibition mechanism follows the cooperative adsorptive model.

Profile improvement during CO_2 flooding in ultra-low permeability reservoirs

Gas flooding such as CO2 flooding may be effectively applied to ultra-low permeability reservoirs, but gas channeling is inevitable due to low viscosity and high mobility of gas and formation heterogeneity. In order to mitigate or prevent gas channeling, ethylenediamine is chosen for permeability profile control. The reaction mechanism of ethylenediamine with CO2, injection performance, swept volume, and enhanced oil recovery were systematically evaluated. The reaction product of ethylenediamine and CO2 was a white solid or a light yellow viscous liquid, which would mitigate or prevent gas channeling. Also, ethylenediamine could be easily injected into ultra-low permeability cores at high temperature with protective ethanol slugs. The core was swept by injection of 0.3 PV ethylenediamine. Oil displacement tests performed on heterogeneous models with closed fractures, oil recovery was significantly enhanced with injection of ethylenediamine. Experimental results showed that using ethylenediamine to plug high permeability layers would provide a new research idea for the gas injection in fractured, heterogeneous and ultra-low permeability reservoirs. This technology has the potential to be widely applied in oilfields.

Design and evaluation of a novel transdermal patch containing diclofenac and teriflunomide for rheumatoid arthritis therapy

The aim of this study was to design a compound transdermal patch containing diclofenac(DA)and teriflunomide(TEF)for the treatment of rheumatoid arthritis(RA).The various organic amines salts of DA were prepared and their forming was confirmed using DSC and FTIR.The percutaneous permeation of organic amines salt of DA was investigated in vitro using a two-chamber diffusion cell with excised rabbit skin as transdermal barrier.The formulation of the patch was optimized in terms of the concentration of percutaneous permeation enhancer and the loading dose of drugs.The pharmacokinetic behavior of the optimal formulation was studies in rabbits and the anti-inflammatory and analgesic effects of the optimal patch were evaluated with the adjuvant arthritis model in rats and the pain model in mice,respectively.The result showed that skin penetration of diclofenactriethylamine(DA-TEtA)salt was better than other organic amine salts.Based on previous study of our laboratory,teriflunomide-triethylamine(TEF-TEtA)significantly enhanced the skin permeation of TEF.10%of azone(AZ)was the best enhancer for the two drugs.The optimal patch formulation was composed of 2%of TEF-TEtA,6%of DA-TEtA and 10%of AZ.The cumulative permeated amount of DA-TEtA in vitro was comparable with that of the commercial diclofenac-diethylamine(DA-DEtA)patch.The absolute bioavailability of TEFTEtA was 42%,which could achieve the therapeutic drug levels.In animal study,the optimized compound patch containing DA-TEtA and TEF-TEtA displayed significant antiinflammatory and analgesic effect,which indicated the potential of the compound patch.

Recent Progress in Developing Crystalline Ion Exchange Materials for the Removal of Radioactive Ions

The nuclear fuel cycle inevitably generates a large amount of radioactive waste liquid,which will pose a serious threat to the ecological environment and human health.Ion exchange method has received wide attention for its easy operation,low cost and no secondary pollution.However,the effective removal of radioactive ions from complex solutions still remains a serious challenge due to their environmental mobility and radiotoxicity.We have developed an efficient strategy to construct crystalline ion-exchange materials by inducing layered or three-dimensional microporous anionic frameworks by organic cations that can be effectively exchanged by radioactive metal ions.This type of materials can be applied effectively to the removal of radioactive ions from complex solutions and the removal mechanism has been deeply clarified by means of single crystal structure analyses,theoretical calculations,etc.This review summarizes our recent progress in the study of synthesis,structures and properties of radioactive ion removals for such type of crystalline ion-exchange materials.