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21.
Cu electroplating is required for the fabrication of Cu/low-k interconnections. The permeation of a plating solution into low-k films during Cu electroplating is a serious challenge for 45-nm nodes and more complex devices. We investigated the influence of Cu electroplating solutions on boron carbon nitride (BCN) as a low-k film. After dipping it into a Cu electroplating solution that contained additives, the BCN film's hydrophilic surface changed to a hydrophobic surface, and the incorporation of water into the BCN film was suppressed by surfactant adsorption. Sulfuric residue was detected on the BCN sample by thermal desorption spectroscopy after treatment in the Cu electroplating solution with additives; however, it was found through electrical measurements that this solution did not affect the leakage current or the dielectric constant of the BCN film. We successfully fabricated an electroplating Cu layer on a BCN film with good adhesion, and we believe that this BCN film is a sufficiently useful material for Cu/BCN integration in LSI.  相似文献   
22.
Production of bacterial cellulose by Acetobacter xylinum ATCC 10821 and 23770 in static cultures was tested from unamended food process effluents. Effluents in cluded low-solids (LS) and high-solids (HS) potato effluents, cheese whey permeate (CW), or sugar beet raffinate (CSB). Strain 23770 produced 10% less cellulose from glucose than did strain 10821 and diverted more glucose to gluconate. Unamended HS, CW, and CSB were unsuitable for cellulose production by either strain, and LS was unsuitable for production by strain 10821. However, strain 23770 produced 17% more cellulose from LS than from glucose, indicating that unamended LS could serve as a feedstock for bacterial cellulose.  相似文献   
23.
氯化银比浊法测定铜箔镀液中微量氯   总被引:2,自引:0,他引:2  
采用氯化银比浊法,在不分离硫酸铜的条件下,直接测定镀铜电解液中微量氯离子。对试验条件和可能存在的干扰进行了研究,榈的加标回收率在98.7% ̄107.0%之间,相对标准偏差在2.7% ̄8.8%之间。方法快速简单,结果满意。  相似文献   
24.
Palm oil mill effluent (POME) is one of the most significant pollutant in the form of wastewater. It could have negative effects on the environment include the emission of biogas and water pollution which comes from discharging the brownish tick POME to the water bodies if not properly managed. Discharge of dark brownish colored of POME directly into water bodies may affect the aquatic life as it will reduce sunlight penetration and suppress the photosynthetic activity. A molecularly imprinted polymer (MIP) for removal of β-carotene from POME has been aimed to develope in this study. The preparation of β-carotene imprinted and non-imprinted polymer (NIP) involves polymerization of β-carotene (or without it) with β-cyclodextrin (β-CD), 9-vinylcarbazole (9VC), tolylene diisocyanate (TDI) and N,N-dimethylformamide (DMF) as the monomer, co-monomer, cross-linker and solvent (porogen), respectively. Analysis from FTIR showed that MIP and NIP have similar characteristic peak with different peaks intensity, indicating the similarity in the backbone structure of polymerization. TGA result displayed high thermal stability with final decomposition at 320 °C for MIP-β-CD-9VC as compared to NIP-β-CD-9VC. The pH study shows that sorption of β-carotene increased with decreasing the pH of POME and the maximum sorption capacities achieved at pH 2 were 10 μg/g and 7 μg/g for MIP-β-CD-9VC and NIP-β-CD-9VC, respectively. The maximum sorption achieved by using 500 mg of MIP as the sorption of β-carotene increased with increasing the dosage of MIP. Kinetic model evaluation has been applied on this prepared materials. The sorption equilibrium data was well described by Freundlich model. The results indicated that the sorption of β-carotene on MIP follows a pseudo–second–order kinetic.  相似文献   
25.
In the Industry 4.0 Era, big data and automation will require precise knowledge that allows one to control, monitor and predict a process. Electroforming, which is the fabrication of free-standing components using electrodeposition, is rapidly gaining acceptance as a sustainable additive manufacturing technology. However, current knowledge of electroforming is based on empirical data, and academic engagement in this area has been limited. This article throws light on some of the complex issues surrounding the electrochemical and chemical behaviour during electroforming, which are yet unresolved. The differences between cathodic reactions in sulfamates and sulfates, ambiguities related to the role of boric acid and paucity of data on anode reactions are highlighted.  相似文献   
26.
A bioassay-directed chemical analysis (BDCA) scheme has been developed which combines a yeast screen for estrogenic activity with LC–MS detection after liquid–liquid extraction and fractionation by size exclusion chromatography. Focusing on sewage-treatment plant (STP) effluents, the approach aims at characterizing the substances responsible for estrogenic effects in aquatic systems. Initial results show a strong response of STP effluent extracts in the yeast screen. Estrone, bisphenol A, and nonylphenol have been identified as substances being partly responsible for observed estrogenic activity. However, confirmation experiments with synthetic samples revealed that the estrogenic effect potentials of the samples could not be completely assigned to specific compounds. Further improvement of the limits of detection of the analytical scheme is needed to enable identification and quantification of potent estrogenic compounds at low concentrations.  相似文献   
27.
Two glass capillary gas chromatographic systems were equipped with inert effluent splitters which allowed simultaneous data acquisition using nonspecific and element-specific detectors. Simultaneous detection was achieved using the nonspecific flame ionization detector (FID) and the Hall® electrolytic conductivity detector (HECD) operated in either the sulfur-or the nitrogen-specific mode. Typical application of the simultaneous detection system as applied to analysis of petroleum residues is briefly described. The Hall electrolytic conductivity detector can be made element specific for halogen-, sulfur-, or nitrogen-containing compounds. Simultaneous detection enhances the information yield from a single sample injection and proves to be a powerful complementary technique when used with computerized gas chromatography/mass spectrometry.  相似文献   
28.
PREPARATIONOFBAGASSEXANTHATES(BX)ANDNICKELREMOVALFROMWASTEWATERBYBXZhongChanggeng;TangDonggong;ChenQiaoyun(DepartmentofChemis...  相似文献   
29.
In this work, the effect of Fento’s reagent on the degradation of residual Kraft black liquor was investigated. The effect of Fenton’s reagent on the black liquor degradation was dependent on the concentration of H2O2. At low concentrations (5 and 15 mM) of H2O2, Fenton’s reagent caused the degradation of phenolic groups (6.8 and 44.8%, respectively), the reduction of reaction medium pH (18.2%), and the polymerization of black liquor lignin. At a high concentration (60 mM) of H2O2, Fenton’s reagent induced an extensive degradation of lignin (95–100%) and discoloration of the black liquor. In the presence of traces of iron, the addition of H2O2 alone induced mainly lignin fragmentation. In conclusion, Fenton’s reagent and H2O2 alone can degrade residual Kraft black liquor under acidic conditions at room temperature.  相似文献   
30.
A novel polyaniline (PANI) coating was prepared on a stainless-steel wire for solid-phase microextraction by electroplating method. For better mechanical strength, the stainless-steel wire was used instead of the fused silica fiber. The electroplating method had advantages of ease of preparation and simple equipments. The PANI fiber was evaluated by analyzing six aromatic amines (aniline, N,N-dimethylaniline, m-methylaniline, 2,4-dimethylaniline, 2-chloroaniline, 3,4-dichloroaniline) in water. After the analytical procedure was optimized, the linearity was from 4.8 to 2.75 x 10(4) microg L(-1) and the detection limits was from 0.019 to 1.06 microg L(-1). Relative standard deviations were found to be 2.02-6.00%. Good recoveries were obtained when wastewater samples were analyzed.  相似文献   
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