Effects of complexing agents on acidic electroless nickel deposition

Our previous study reported the influences of different complexing agents on electroless nickel （EN） by examining the properties of the deposits. In the present work, the effects of four common-used complexing agents on EN deposition rate and the stability of solution pH values were examined, either with an acetic pH buffer agent or absent of them. It is indicated that the pH buffeting effect of them is dominative when the EN solution is lack of the pH buffer. Under this situation, the EN deposition rate increases with the concentration of complexing agents increasing. The EN deposition rate decreases with fin＇ther adding the complexing agent when the solution already has enough pH buffer capability. Electrochemical impedance spectroscopy obtained during EN deposition illustrates that, in this case, the enhanced reaction resistance is the main reason for a lower deposition rate. However, the influence of polarization caused by mass transfer is not negligible at high complex ratio for sodium citrate and malic acid EN solutions.

Structure and Shape Control of Hydrothermally Synthesized PbTiO_3 --Effects of pH and Complexing Agents

Tabular PE PbTiO 3, spherical PY PbTiO 3, and acicular PX PbTiO 3 powders were hydrothermally synthesized from triethanolamine(TEA) complexed precursor; clubbed PE PbTiO 3 powders were obtained from diethanolamine(DEA) complexed precursor. The effects of pH of the hydrolyzation as well as complexing agents including TEA, DEA, and MEA(monoethanolamine) on the structure and the morphology of PbTiO 3 powders are discussed. The optimal conditions for hydrothermal syntheses of acicular and clubbed PbTiO 3 powders have been established. The products were characterized by means of XRD, TEM and other techniques.

Solvent extraction and separation of light rare earth elements (La, Pr and Nd) in the presence of lactic acid as a complexing agent by Cyanex 272 in kerosene and the effect of citric acid,acetic acid and Titriplex Ⅲ as auxiliary agents

At present, the use of rare earth elements（REEs） has become an inevitable necessity in many modern industries. In general, liquid extraction is the best commercial method for extracting REEs due to its ability to control high volumes of liquids with electrical load. With the aim of improving a separation technology that would be superior to the existing extraction systems, the extraction behaviors of La（Ⅲ）,Pr（Ⅲ）, and Nd（Ⅲ） from an HCI medium with Cyanex 272 in the presence of the complexing agent lactic acid（HLac） and auxiliary agents citric acid（H3 Cit）, acetic acid（HAc）, and Titriplex Ⅲ have been reported.The effect of pH and lactic acid concentration has been examined. The use of lactic acid as a complexing agent leading to a high extraction of REEs with Cyanex 272 at pH = 5 was compared with systems without lactic acid. The results show that the use of acetic acid along with lactic acid leads to an increase in the extraction percentage of LREEs. While use of citric acid and Titriplex Ⅲ reduces the extraction percentage of LREEs. Finally, the presence of Titriplex Ⅲ together with lactic acid could lead to an increase in the separation factor of Pr and Nd.

Effect of FA/O complexing agents and H_2O_2 on chemical mechanical polishing of ruthenium in weakly alkaline slurry

This paper investigated the effect of FA/O and hydrogen peroxide （H2O2） on ruthenium （Ru） removal rate （RR） and static etching rate （SER）. It was revealed that Ru RR and SER first linearly increased then slowly decreaseed with the increasing H2O2 probably due to the formation of uniform Ru oxides on the surface during polishing. Their corrosion behaviors and states of surface oxidation were analyzed. In addition, FA/O could chelate Ru oxides （such as （RuO4）2- and RUO4- changed into soluble amine salts [R（NH3）4] （RuO4）2） and enhance Ru RR. The non-ionic surfactant AD was used to improve the Ru CMP performance. In particular, the addition of AD can lead to significant improvement of the surface roughness.

Combination of on-line preconcentration by di(2-ethylhexyl) phosphoric acid resin in the presence of complexing agent with microwave plasma-atomic emission spectrometry for the determination of rare earths

The adsorption of rare earths,lanthanum,cerium,neodymium,and yttri um by di(2-ethylhexyl) phosphoric acid(D2EHPA) resin in the presence of a compl exing agent,EDTA,was investigated. Flow injection was selected as the injectin g method. Various parameters,sample pH,sample loading time,sample flow rate,EDTA concentration,EDTA flow rate,eluent concentration,and eluent flow rate,were studied and optimized. Under the optimum conditions,the method allowed the determination of rare earths with detection limits of 1.09 μg/L(lanthanum),3 .31 μg/L(cerium),2.05 μg/L(neodymium),and 1.25 μg/L(yttrium) . High repea tabilities were obtained for all the four rare earths(RSD【5%) . The proposed met hod was applied to the determination of the rare earths in water samples with a recovery range of 95.8%-103.3%.

Structure, properties and application to water-soluble coatings of complex antimicrobial agent Ag-carboxymethyl chitosan-thiabendazole

The structure, properties and application to water-soluble coatings of a new complex antimicrobial agent Ag-carboxylmethyl citosan-thiabendazole （Ag-CMCTS-TBZ） prepared from different materiel ratios were reported. The silver ions were preferably coordinated with the free-NH2 groups and the -OH groups of secondary alcohol and carboxyl in CMCTS. TBZ preferably bonded to carboxyl group in CMCTS by electrostatic force and hydrogen bonding. Increase in silver ions content in the complex agent improved to some limited extent the antibacterial activity, but enhanced coloring and cost of the complex agent. Increase in TBZ content resulted in increase of antifungal activity, but decrease of water solubility of the complex agent. The antimicrobial MICs of the complex agent to Esherichia coil, Staphylococcus aureus, Candida albicans, Aspergillus niger, Mucor sp. were 20 -80, 15 -60, 20 - 55, 40 - 250, and 400 - 1700 mg/kg, respectively. Addition of 0.1% of this complex agent to acrylic emulsion paint made the paint without substantial change in color, luster, viscosity, odor or pH value, but with an excellent and chronically persisting broad-spectra antimicrobial activity.

Application study on complex wetting agent for dust-proof after gas drainage by outburst seams in coal mines

After gas drainage, the outburst seam is dry and, consequently, during subsequent mechanized mining, unwanted dust production is extensive. Because the hard dustfall typically has a small particle size it contains a high percentage of respirable dust. Considering these factors, this paper improved the efficiency of dustfall by reducing the surface tension of the liquid used as a wetting agent, then configuring five kinds of wetting agents by adopting various doses and types of surfactants, neutral inorganic salts and chemical additives, etc. After purchasing DA-85 and SRJ-1 wetting agent, the surface tension and critical micelle concentration of seven kinds of wetting agents were measured using the capillary rise method. Wetting agent A was confirmed to have the best comprehensive effect. The experiments were optimized by measuring and comparatively analyzing contact angles of pure water, SRJ-1 wetting agent and wetting agent A on the surface of different coal samples using a contact angle measurement instrument （HARKE- SPCA）. By comparative analysis, dust-proof effects of seam, dynamic pressure water infusion and high- pressure spray in the tunneling face at the Daning coal mine using pure water, wetting agent SRJ-1 and A, it was determined that after using wetting agent A, the average dust concentration in the place of the mining machine driver, 10 m and 110 m away from the tunneling front is approximately 300 rag/ m^3, 240 mg/m^3 and 100 mg/m^3, respectively, This practice increased the dust-proof efficiency dramati- cally and achieved a good comprehensive dust-proof effect.

Highly Reversible Zn Metal Anodes Enabled by Increased Nucleation Overpotential

Dendrite formation severely compromises further development of zinc ion batteries. Increasing the nucleation overpotential plays a crucial role in achieving uniform deposition of metal ions. However, this strategy has not yet attracted enough attention from researchers to our knowledge. Here, we propose that thermodynamic nucleation overpotential of Zn deposition can be boosted through complexing agent and select sodium L-tartrate(Na-L) as example. Theoretical and experimental characterization reveals L-tartrate anion can partially replace H_(2)O in the solvation sheath of Zn^(2+), increasing de-solvation energy. Concurrently, the Na^(+) could absorb on the surface of Zn anode preferentially to inhibit the deposition of Zn^(2+) aggregation. In consequence, the overpotential of Zn deposition could increase from 32.2 to 45.1 mV with the help of Na-L. The Zn-Zn cell could achieve a Zn utilization rate of 80% at areal capacity of 20 mAh cm^(-2). Zn-LiMn_(2)O_(4) full cell with Na-L additive delivers improved stability than that with blank electrolyte. This study also provides insight into the regulation of nucleation overpotential to achieve homogeneous Zn deposition.

Study on the CAN Search Model based on BDI Agent

The main purpose of establishing a complex agent network （CAN） search model is to specifically model each type of the relationships between different types of Agent structure domain and make it easier to be implemented in the existing programming language environment. Under the guidance of complex Agent network method, CAN search process was analyzed, a dynamic search model description was established based on CAN search process, and then individual Agent modelling and the memory and processing of the thinking attributes such as beliefs, desires and intentions in CAN search process were mainly introduced from the individual level; all sorts of Agent conceptual models and Agent type descriptions for CAN search model were designed by introducing BDI Agent; the states and behaviors of the Agent involving in CAN search process were clearly defined.

Crystal Structures of N, N'-Bis (4-chlorophenyl)-1, 10-diaza-18-crown-6 and Its Complex with Ba (SCN)_2

The title compounds,C_(24)H_(32)Cl_2,N_2O_4(I)and C_(26)H_(32)BaCl_2N_4O_4S_2 (Ⅱ)have been synthesized and crystal structures determined. The crystallographic data are as follows: (I)M_r=483. 44,orthorhombic, space group P2_12_12_1,a= 4. 852 (1), b= 11. 989(2), c=41. 231 (8) A, V=2398. 7(8) A￣3, Z=4, μ(MoKa)=3. 07 cm￣(-1), D_c=1. 338 g/cm￣3, F(000)=960, R=0. 0678, R_w=0. 0514. (Ⅱ) M_r=736.93, monoclinic, space group P2_1/c, a=8. 801 (2), b=11. 653(9) , c=15. 756(6) A,β=105. 96(3)°, V=1553. 7(14) A￣3, Z= 2, μ(MoKa)=16. 58 cm￣(-1), D_c=1. 575 g/ cm￣3, F(000)= 740. In compound Ⅱ, the Ba cation is coordinated by four oxygen atoms, two mitrogen atoms of diazo-18-crown-6 and two nitrogen atoms from SCN￣- to form a distorted D_(6h) geometry with the Ba￣(2+) at the center of crystallographic symmetry.

Development and Performance Study of CaCO_3 Modified PP Spun-Bonded Nonwovens

The manufacturing process of CaCO3 modified Polypropylene (PP) spun-bonded nonwovens was studied. Then the effect of the additive amount of CaCO3 on mechanical properties of the product was analyzed, and a compatible mechanism between CaCO3 particles and the main component of PP was established. In the end, the mechanical performance of the products was studied when the natural light degradation was changed. The experiment results show that after adding CaCO3 to the PP spun-bonded nonwovens and through the application of complex coupling agent and organic modification, hardcore of rigid particles and polymer composite elastomers can be combined together tightly and disperse rapidly and evenly in the main part of PP. In addition, CaCO3 can catalyze the light degradation of PP spun-bonded nonwovens. The larger the content of CaCO3 is, the faster the light degradation will be.

Morphologies and corrosion resistances of electroless Ni-P coated nanoporous coppers

In order to improve the corrosion resistance of nanoporous coppers （NPCs）, the electroless Ni-P coated NPCs were prepared in plating solutions with different pH values （5, 8, 11） and complexing agent （actic acid, citric acid）. The morphologies and cor- rosion resistances of the as-prepared samples were investigated. The results showed that the double complexing agent com- posed of lactic acid and citric acid is relatively suitable for preparing the Ni-P coated NPC with three-dimensional continuous interpenetrating ligament-channel structures, and the uniform ligaments and nanoporous channels could be obtained at pH8. The Ni-P coated NPC showed higher corrosion potentials than NPC in H2S04, NaOH and NaC1 corrosion solutions.

Exploring the role of --NH2 functional groups of ethylenediamine in chemical mechanical polishing of GCr15 bearing steel

Ethylenediamine with two-NH2 functional groups was used as a critical complexing agent in chemical mechanical polishing(CMP)slurries for a high carbon chromium GCr15 bearing steel(equivalent to AISI 52100).The polishing performance and corresponding mechanism of-NH2 functional groups were thoroughly investigated as a function of pH.It is revealed that,when polished with ethylenediamine and H2O2-based slurries,the material removal rate(MRR)and surface roughness Ra of GCr15 steel gradually decrease as pH increases.Compared with acidic pH of 4.0,at alkaline pH of 10.0,the surface film of GCr15 steel has much higher corrosion resistance and wear resistance,and thus the material removal caused by the pure corrosion and corrosion-enhanced wear are greatly inhibited,resulting in much lower MRR and Ra.Moreover,it is confirmed that a more protective composite film,consisting of more Fe3+hydroxides/oxyhydroxides and complex compounds with-NH2 functional groups of ethylenediamine,can be formed at pH of 10.0.Additionally,the polishing performance of pure iron and a medium carbon 45 steel exhibits a similar trend as GCr15 steel.The findings suggest that acidic pH could be feasible for amine groups-based complexing agents to achieve efficient CMP of iron-based metals.

Synthesis, chemical nuclease activity, and in vitro cytotoxicity of benzimidazole-based Cu(Ⅱ)/Co(Ⅱ) complexes

In this study, novel mono/di-nuclear Cu（p-2-bmb）（OH）（Cl O4）（1） and Co2（p-2-bmb）2Cl4（2）（p-2-bmb = 1-（（2-（pyridin-2-yl）-benzoimidazol-1-yl）methyl）-1H-benzotriazole） complexes with the nitrogen heterocyclic benzimidazole-based ligand were synthesized and characterized. The two complexes showed antiproliferative effects in various carcinoma cell lines, especially complex 1 in the SMMC7721 tumor cell line. Complex 1 was also able to pass through the cell membrane and enter the nucleus and mitochondrion. An analysis of in vitro chemical nuclease activity revealed that complex 1 partially intercalated to calf thymus DNA and exhibited strong unwinding activity against p BR322 superhelical plasmid DNA. The comet assay and flow cytometry analysis confirmed that 1 caused extensive DNA damage and arrested SMMC7721 tumor cells at G2/M phase of the cell cycle, leading to loss of mitochondrial membrane potential and apoptosis. These results suggest that these benzimidazole-based metal complexes could be potential anti-cancer agents.