A novel green inhibitor for C-steel corrosion in 2.0 mol·L^-1 hydrochloric acid solution

The corrosion inhibition characteristics of aqueous extract of seeds of Melia azedarach L.(MA) have been studied as eco-friendly green inhibitor for corrosion control of C-steel in 2 mol·L^(-1) HCl solution by gravimetric and electrochemical methods. The results depict that, the extract inhibits efficiently the corrosion of carbon steel in hydrochloric acid. The efficiency of extract is increased with increasing the extract concentration but independent on the studied temperature. The adsorption of the extract components onto the steel surface was found to be spontaneous, and follows Langmuir adsorption isotherm. The surface morphology of C-steel, in the absence and presence of MA extract in 2.0 mol·L^(-1) hydrochloric acid solution, was studied using scanning electron microscopy(SEM).

Intercalation and Stability of Layered Semiconductive Material in Corrosive Environment

The intercalation of 4-methyl pyridine （4-picoline） into layered semiconductive material （MnPS3） and the stability of the resulting materials in corrosive environments （water, HCI and open atmosphere） were investigated. Powder X-ray diffraction （XRD） indicated that the presence of water and hydrochloric acid greatly influenced the existing form of intercalation and its orientation in the interlayer of the host. Atmospheric environment （open air） affected the guest orientation in the interlayer of the host material. Phase transformation occurred and the material was stable. The intercalated compounds could be indexed in the trigonal unit cell. The XRD patterns exhibited sharp hkl reflections of the intercalated compounds, which formed in water and HCI, confirming that the materials were well crystalline and stable in corrosive environments.

二氧化碳在地球表层的循环

1.引言由二氧化碳等温室效应气体的增加造成的全球变暖问题是当前自然科学和政治生活的中心课题之一。从1958年起在夏威夷摩纳罗阿进行的大气中二氧化碳含量测定表明,大气中二氧化碳的浓度每年增加1～1.5ppm。根据此增加量和化石燃料消费量增加曲线及未来能源使用情况,预计到21世纪中叶,由于二氧化碳等温室效应气体增加将使地表平均气温增加1.5～4.5℃。

Corrosion Penetration and Crystal Structure of AA5022 in HCl Solution and Rare Earth Elements

Al-alloy (AA5022) corrosion penetration (CP) and crystal structure were investigated after running static immersion corrosion tests in 1 mol/L HCl solution and different concentrations of rare earth elements (La3+), (Ce3+) and their combination, at different temperatures. X-ray diffraction (XRD) was used to examine the surface structure before and after immersion, and secondary electron detector (SED) was operated to study surface morphology. In 1 mol/L HCI solution the corrosion penetration increased with increasing temperature and immersion time. The increase of La3+ concentrations up to 1000×10-6 g/L led to the decrease in the corrosion penetration, and the decrease in Ce3+ concentrations up to 50×10-6 g/L decreases the corrosion penetration of the alloy. Mix3 (combination of La3+ and Ce3+) dramatically reduced the corrosion penetration. This suggests that a synergistic effect exists between La3+ and Ce3+. The reaction kinetics both in absence and presence of La3+ and Ce3+ and their combination would follow a parabolic rate law. The XRD patterns revealed that the intensities of certain hkl phases are affected. The crystalline structure has not been deformed either before or after testing and there are no additional peaks except that of the as-received alloy. In the case of accelerating CP, the surface morphology shows that the roughness and voids of surface are increased.

Recovery of some valuable elements from lamprophyre dykes in the Abu Rusheid area, Southeastern Desert, Egypt

In the Abu Rusheid area, Southeastern Desert of Egypt, polymineralized (HREEs, U, Zn and Pb) lam-prophyre dykes are recently recorded. The lamprophyre dykes cut cataclastic rocks along share zones in NNW-SSE trends. The secondary U-minerals are essentially represented by uranophane, kasolite, torbernite and autunite. Ex-perimental work was carried out on the lamprophyre dykes for the recovery of uranium and other valuable elements (e.g. Zn, Pb and Al) from 50 kg of technological sample. The optimum conditions were: 100 g/L sulfuric acid con-centration, 1:5 S/L (solid/liquid) and soaking for 15 days at room temperature. The leaching efficiencies for the re-covery of uranium and other elements like Al, Zn and Pb were 40, 33.6, 98.8 and 78, respectively.

SYNTHESIS,CHARACTERIZATION OF DIAMIDE-DIIMIDE-DIAMINES BASED ON L-CYSTEINE AMINO ACID AND THEIR EFFECT ON THE THERMAL PROPERTIES OF DIGLYCIDYL ETHER OF BISPHENOL-A(DGEBA)

The curing behavior of diglycidyl ether of bisphenol-A(DGEBA) with aromatic diamide-diimide-diamines having aryl ether,sulfone and methylene linkages was studied by differential scanning calorimetry(DSC).Nine diamide-diimide-diamines of varying structure were synthesized by reacting 1 mole of dianhydride with 2 moles of L-cysteine(S) in a mixture of acetic acid and pyridine(3:2 V/V) followed by activation with thionyl chloride(SOCl_2) and then condensation with excess of diamines.Structural characterization...

Adsorption of Orange II Dye using Activated Carbon Produced from Iraqi Date-Palm Stones

A synthetic activated carbon was manufactured from date-palm stones using zinc chloride, cadmium chloride and sodium chloride at different temperatures and atmospheres. Specific surface area, RC and pH were measured and the activated carbon was used to absorb the orange II dye. Adsorption equilibrium was also studied, and it was found that the adsorption process on the synthetic activated carbon fit very well with the Langmuir isotherm model and less fit with Freundlich isotherm model. The specific surface area was highly affected by increasing temperature of combustion while the atmosphere of combustion had a little effects on surface area. The results showed that the atmosphere and temperature had no such effect on RC values. However, the RC of zinc chloride samples gave the highest values compared to that of cadmium chloride or sodium chlorides. The values of pH indicated an acid medium for cadmium chloride to alkali medium for sodium chloride, while the samples of zinc chloride showed a neutral medium.

AN AB INITIO N_(2)-H_(2)O POTENTIAL FOR COMPUTER SIMULATIONS

N2-H2O system was studied by ab initio SCF calculations with a 6-31G** basis set. The results were fitted to an analytical funotion assuming psirwise additivity for the interaction between individual centres. The analytical functions were Lennard-Jones 10-6 and exponential form. A satisfactory fitting result was achieved by the simulated anneal algorithm. Special care was paid to repulsive region, which gives the important contribotions to the formation of the first solvation shell of apoler solutes.

Manganese vanadium oxide composite as a cathode for high-performance aqueous zinc-ion batteries

The development of clean renewable energy and energy storage devices is of great significance under the present energy crisis and environmental pollution background.Aqueous zinc-ion battery(ZIB)has become one of the most promising energy storage devices due to its high capacity,safety and low cost.However,the application of ZIB cathode is usually limited by low capacity and poor stability.Herein,we propose a novel heterostructure MnO/MnV_(2)O_(4)composite material composed of MOF derivatives and spinel with dual active components as cathode for ZIBs.Benefited from substantial framework of MOF derivatives and the synergistic effect of heterostructures,MnO/MnV_(2)O_(4)exhibits excellent rate performance(342 m Ah/g at 0.1 A/g,261 mAh/g at 15 A/g)and cycling performance(198.9 mAh/g at 10 A/g after 2000 cycles)in3 mol/L Zn(CF_(3)SO_(3))2electrolytes.This work extends the range of developing high-performance cathodes for ZIBs under high current density and is expected to enlighten the optimization of commercial energy storage devices.

鞣液和皮革中Al2O3的分析 第二部分：用络合滴定法分析经铝鞣和植铝鞣后皮样的Al2O3

本文介绍了测定经过铝鞣和植铝混合鞣后皮样中的Al2O3的含量。取2．000g的革样品，在700℃下灼烧成灰，然后加入1．5g Na2B4O7，在950℃，熔融加热20min，使灰样中的Al2O3熔化，再加入1mol／L硝酸即可使熔融物溶解。溶解后转移到250ml的烧瓶中，加水稀释至刻度线。用EDTA标准溶液和Pb（NO3）2标准溶液反滴定试样溶液。通过这种方法来分析测定经云杉-铝和坚木栲胶-铝植铝鞣剂鞣制过的小绵羊皮和猪皮革中的Al2O3。该方法灵敏性高，皮样中Al2O3含量的检测范同是可以检测至0．04％到2．39％。熔化过程中Al2O3的损失不高于4％。

Diclofenac sodium aqueous systems at low concentrations: Interconnection between physicochemical properties and action on hydrobionts

Diclofenac sodium(DS) is a widely used nonsteroidal anti-inflammatory drug(NSAIDs).NSAIDs are poorly removed during standard wastewater treatment.The consequences of the presence of NSAIDs in rivers and lakes at 10-11–10-8 mol/L are not yet established;therefore, ecotoxicologists have focused their efforts on studying the effect of lowconcentration NSAIDs on fish and hydrobionts, and also on predicting the potential risks to humans.Literature provides some information about the bioeffects of some NSAID solutions in low concentrations but there is no physicochemical explanation for these phenomena.Studying the physicochemical patterns of DS solutions in the low range of concentrations and establishing an interconnection between the solutions’ physicochemical properties and bioeffects can provide a conceptually new and important source of information regarding the unknown effects of DS.The physicochemical properties and action of DS solutions on Ceriodaphnia affinis cladocerans,Paramecium caudatum infusoria, Chlorella vulgaris unicellular green algae, as well as on the growth of the roots of Triticum vulgare wheat seeds, were studied in the calculated concentration range of 1 × 10-3–1 × 10-18 mol/L.The relationship between these phenomena was established using the certified procedures for monitoring the toxicity of natural water and wastewater.It was shown for the first time that water solutions of DS are dispersed systems in which the dispersed phase undergoes a rearrangement with dilution, accompanied by changes in its size and properties, which affects the nonmonotonic dependences of the system’s physicochemical properties and could cause nonmonotonic changes in action on hydrobionts in the low concentration range.

“Controlled” and “Living” Cationic Polymerizations:Another Way Towards Well Defined Polymer Architectures and Materials

1 Results No doubt that one of the major breakthroughs in polymer chemistry was the discovery and the progressive implementation of the "living" and "controlled" polymerizations.These now widely used techniques allow not only to control with an extreme precision the molar masses and their distributions but also to synthesise easily a broad variety of architectures from block and graft copolymers,miktoarms stars,to polymer brushes,hyperbranched polymers,dendrimers,etc....They opened an immense domain of ...