Showing papers on "Sodium hypophosphite published in 2005"
TL;DR: The work in this article summarizes the research conducted in our laboratory over the past five years, with a focus on the reactions of hypophosphorous acid derivatives, including room-temperature radical addition and palladium-catalyzed addition.
148 citations
TL;DR: The structural information of the nanoparticles synthesized at room temperature is proposed that the formation of the cyclic penta-twinned structure is due to the stacking fault and the intrinsic equilibrium structures of the lower energy.
Abstract: Silver nanowires are synthesized by simple reduction of the silver ions with reductants such as glucose, sodium citrate, and sodium hypophosphite, etc., in the absence of the so-called surfactants or capping reagents at the temperature from 80 to 200 °C. Regardless of the reductants, the nanowires prepared at a given temperature are uniform in diameters, ranging from 30 to 50 nm at 100 °C. Nanoparticles coexist with nanowires in the products with larger diameters (usually larger than 50 nm). We find that all the silver nanowires in the as-prepared products are of cyclic penta-twinned structure, where five crystallites bond by the {111} facets. We propose that the intrinsic factor of the cyclic penta-twinned structure, i.e., the angular mismatch of the five crystallites in forming a gapless rod, controls the size of the nanowires and guides the directional growth of the nanowires with {110} as the active facets. The nanoparticles in the products are aggregates of imperfect penta-twinned crystals, which inh...
138 citations
TL;DR: In this paper, an electroplating bath, using chromium trivalent ions instead of its hexavalent ions because of its toxicity, was designed for black chromium coating to produce a good metallurgical and light properties at low cost and reproducibility.
49 citations
TL;DR: The room-temperature radical addition of sodium hypophosphite to terminal alkynes produces the previously unknown 1-alkyl-1,1-bis-H-phosphinates in moderate yield, providing a simple purification procedure and the opportunity for multigram synthesis.
47 citations
TL;DR: The size- and composition-controlled synthesis of Ni-P nanospheres from nickel chloride and sodium hypophosphite has been systematically investigated by changing the conditions, such as the ratio of the starting materials, pH value, and reduction temperature and found that when the starting ratio of H2PO2(-)/Ni2+ was changed the size and chemical composition of the nanoparticles changed simultaneously.
Abstract: The size- and composition-controlled synthesis of Ni-P nanospheres from nickel chloride and sodium hypophosphite has been systematically investigated by changing the conditions, such as the ratio of the starting materials, pH value, and reduction temperature. It was found that when the starting ratio of H2PO2(-)/Ni2+ was changed the size and chemical composition of the nanoparticles changed simultaneously. Within a suitable pH range, the phosphorus content was altered without affecting the particle size. Increasing the reduction temperature resulted in smaller Ni-P nanospheres but invariable phosphorus content. The Ni-P nanospheres were amorphous when the phosphorus content was higher than 10.0 mol %, while lower phosphorus content led to a composite of amorphous Ni-P and face-centered cubic (fcc) Ni. During postsynthesis calcinations, amorphous Ni-P nanospheres with a low phosphorus content directly crystallized to Ni3P and fcc Ni. However, the specimens with high phosphorus content crystallized via some intermediate phases such as Ni5P2 and Ni12P5. In the latter, an amorphous P-rich shell was developed simultaneously. A preliminary catalytic test of growth of carbon nanofibers on the Ni-P nanospheres has been carried out.
46 citations
TL;DR: In sequential adsorption and desorption cycles, the lead uptake capacity on carboxylated alginic acid was relatively maintained through cycles 1-5, and concentration factor increased as S/L ratio which is defined as the ratio of adding amount of adsorbed and volume of desorbing agent increased.
39 citations
TL;DR: In this article, two mechanisms of phosphorus incorporation with nickel in electroless plating nickel are studied using X-ray fluorescence spectrometer (XRF) and cyclic voltammetry (CV).
Abstract: The two mechanisms of phosphorus incorporation with nickel in electroless plating nickel are studied using X-ray fluorescence spectrometer (XRF) and cyclic voltammetry (CV). The results of XRF and CV data on the effect ofsingle and double complexing agents on deposition rate and deposit composition indicate that nickel chelates can catalyze phosphorus generation, i.e., the mechanism of interface complex heterocatalysis on phosphorus incorporation with nickel. Furthermore, the choice principle to complexing agents for low-phosphorus electroless nickel bath was proposed based on it. Additionally, the direct mechanism of phosphorus generation can explain how single sodium hypophosphite can be reduced on nickel substrate on the CV curve. Finally, the optimal condition for low-phosphorus electroless nickel plating baths was determined. The experimental results support the explanation of the proposed mechanism.
38 citations
TL;DR: In this article, a temperature sensitive random linear copolymer of N-tert-butylacrylamide (NTBA) and acrylamides (Am) was synthesized by the solution polymerization method, using regulated dosing of comonomers.
Abstract: Temperature sensitive polymer hydrogels are being extensively studied because of their potential applications in the biomedical, robotics, and chemical industries. However, major hurdles in their development have been their slow response, low efficiency (swelling/deswelling ratios), and poor mechanical properties due to difficulty in processing them into mechanically strong and fine structures. Fibers made from such polymers would be highly desirable. A temperature sensitive random linear copolymer of N-tert-butylacrylamide (NTBA) and acrylamide (Am) was synthesized by the solution polymerization method, using regulated dosing of comonomers. Using a novel approach, a high molecular weight poly(N-tert-butylacrylamide-ran-acrylamide::27 : 73) has been converted to insoluble strong fibers with fineness of 30–50 microns by solution spinning, drawing, and subsequent crosslinking. Fibers were solution spun in acetone using a 14% copolymer solution in acetic acid with polycarboxylic acid as a crosslinker and sodium hypophosphite as a catalyst. The crosslinks were formed, subsequent to drawing, between reactive amide side groups of the acrylamide moiety of the polymer and the carboxylic acid group of the crosslinker by thermal treatment at 160°C. The transition temperatures of the crosslinked fibers were found to shift towards the lower temperature from 37°C (in linear copolymer) to 22–25°C. These engineered fibers display sharp temperature sensitivity, extremely high reversible change in dimensions (1000% in diameter and ∼ 70% in length), and extremely fast response time (< 20 s for expansion and < 2 s for contraction). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 681–688, 2005
14 citations
TL;DR: In this paper, the authors studied the kinetics of the cathodic reduction of hypophosphite anions in aqueous solutions and showed that the product of the reduction is phosphorus.
Abstract: The kinetics of the cathodic reduction of hypophosphite anions in aqueous solutions is studied as a function of the electrode nature, the sodium hypophosphite concentration, and the solution pH. It is shown that the product of the reduction of hypophosphite anions is phosphorus. A scheme is proposed for the reduction process, according to which the phosphorus formation can proceed via two parallel routes—electrochemical and chemical—whose realization depends on the nature of the metal catalyst.
8 citations
Patent•
21 Sep 2005
TL;DR: In this article, a surface treating technique of materials, especially to a chemical nickel plating solution at medium-temperature, is presented, which applies to a compound complexing agent system, to make the nickel ion in the best complexing condition in the solution, which is lower the activation energy of nickel deposit reaction.
Abstract: The invention directs to a surface treating technique of materials, especially to a chemical nickel plating solution at medium-temperature. The solution is consisting of nickel sulfate, sodium hypophosphite, sodium citrate, lactic acid, sodium acetate and water. It applies to a compound complexing agent system, to make the nickel ion in the best complexing condition in the solution, which is lower the activation energy of nickel deposit reaction, so the working temperature of the solution is dropped, at the same time the stability of the nickel ion in the solution and the sedimentation velocity of the solution improved, and the alloying gild is of excellent property.
6 citations
Patent•
31 Aug 2005
TL;DR: A plating liquid for chemically plating the magnetic NiCoW film on the surface of NiTi alloy is an aqueous solution containing nickel sulfate, cobalt sulfate and ammonium sulfate as discussed by the authors.
Abstract: A plating liquid for chemically plating the magnetic NiCoW film on the surface of NiTi alloy is an aqueous solution containing nickel sulfate, cobalt sulfate, sodium tungstate, sodium hypophosphite, sodium citrate and ammonium sulfate. Its chemical plating process includes such steps as alkali washing of said surface of NiTi alloy, acid washing, sensitizing, activating, immersing it in said plating liquid and chemical plating. The plated product can be used as the medical magnetic scaffold for physiotherapy and chemicotherapy.
Patent•
27 Apr 2005
TL;DR: In this paper, the chemical plating Ni-P solution for the surface treatment of micro mechanical material includes soluble Ni salt, sodium hypophosphite, sodium acetate, and water.
Abstract: The chemical plating Ni-P solution for the surface treatment of micro mechanical material includes soluble Ni salt, sodium hypophosphite, sodium acetate and water, the molar ratio between soluble Ni salt and sodium hypophosphite is 0.25-1.20, that between sodium acetate and soluble Ni salt is 0.20-1.50, and that between water soluble Ni salt is 300-600. The chemical plating process of utilizing the chemical plating Ni-P solution in the surface treatment of micro mechanical material includes cleaning the surface, sputtering one Ni lining layer, painting photoresist and photoetching, setting inside the chemical plating Ni-P solution to produce oxidation-reduction reaction while maintaining in certain temperature, taking out the substrate, cleaning and drying, degluing inside degluing liquid and maintaining the temperature in protective atmosphere to obtain homogeneous Ni-P coating of submicron to submillimeter level thickness and controllable shape.
Patent•
23 Nov 2005
TL;DR: In this paper, a self-lubrication composite electroless plating layer is obtained by using different suitable surfactants depending on different grains to improve Zeta potential of the grain surfaces and suspensibility of the grains in plating solution through adsorption effect of different grains on different surfactant so as to further realize codeposition of grains.
Abstract: The present invention relates to a preparation method by self-lubrication composite electroless plating. It belongs to the field of electroless plating. The procedure is: 1) Fluorine carbon surfactant C20H20F23N2O4I which is commonly used for foam extinguisher is dissolved in PTFE latex emulsion to form mixture A, and SiC or Si3N4 or Al2O3 is dissolved in cetyl trimethyl ammonium bromide to form mixture B. 2) Preparation of plating solution, i.e. nickel sulfate, lactic acid, sodium acetate, sodium hypophosphite, propenysulfocarbamide are added in plating cell at room temperature, and pH is adjusted with sodium hydroxide. 3) Composite electroless plating: the mixture said A and said B are added in the plating solution prepared in step 2) and then heated. Consistent stirring is kept during plating and then self-lubrication composite electroless plating layer is obtained. The invention adopts different suitable surfactants depending on different grains to improve Zeta potential of the grain surfaces and suspensibility of the grains in plating solution through adsorption effect of different grains on different surfactants so as to further realize co-deposition of grains.
Patent•
19 Jan 2005
TL;DR: In this article, a chemical plating solution and its use in low concentration standard gas packaging container which comprises, by using sodium hypophosphite as reducing agent, using nickel sulfate as the main salt as well as addition complexing agent, accelerating agent, stabilizing agent.
Abstract: The invention relates to a chemical plating solution and its use in low concentration standard gas packaging container which comprises, by using sodium hypophosphite as reducing agent, using nickel sulfate as the main salt as well as addition complexing agent, accelerating agent, stabilizing agent, wherein the inner surface of the container employs 5-15% H2SO4 as activating liquid, coating inert layer inside the container, conducting chemical plating and proceeding hole sealing treatment with CrO3.
Patent•
05 Jan 2005
TL;DR: In this article, a water-phase synthesizing method of maleic anhydride-vinyl acetate polymer cleaner was proposed, using maleic and vinyl acetate as raw materials, using water as solvent, and using an oxidation reduction system as initiator to make free radical polymerization.
Abstract: The invention provides a water-phase synthesizing method of maleic anhydride-vinyl acetate polymer cleaner, using maleic anhydride and vinyl acetate as raw materials, using water as solvent, and using an oxidation reduction system as initiator to make free radical polymerization It introduces a reducing agent sodium hypophosphite in original initiator ammonium persulphate to compose an oxidation-reduction system, increasing initiating efficiency of the original initiator and more beneficial to the generation of polymerization reaction, and thus able to reduce bromine value of product and improving cleaning property of product
Patent•
12 Oct 2005
TL;DR: A process of preparing coating agent of Ni-Ti alloy coved by Ni-Co-Wo membrane is described in this paper, which contains nickelous sulfat,5-13g/L, cobaltous sulfate,23-30 g/L. pH is 8-10.5.
Abstract: A process of preparing coating agent of Ni-Ti alloy coved by Ni-Co-Wo membrane. It contains nickelous sulfat,5-13g/L, cobaltous sulfate,23-30 g/L, natrium wolframicum,0.3-3.3 g/L, sodium hypophosphite,17-25g/L, natrium citricum, 26-36g/L, (NH4)2SO4, 40-70g/L, medicine, 100-1000mg/L g/L. pH is 8-10.5. Wash the surface of of Ni-Ti alloy with alkali and acid. Then put it into coating agent to obtain metal membrane.
Patent•
11 May 2005
TL;DR: The Ni-P alloy coating is of fine corrosion-proof, containing 10-30g nickel sulfate, 20-40g sodium hypophosphite, 5-20g sodium acetate, 12-60g complexing agent and 0.002-0.01g complex stabilizer, with pH value of 4.5-5.0.
Abstract: The invention relates to a chemical Ni-P alloy-plating liquid and its process. The liquid is stable, works fast, has long service life, and does not contain chromium. So, it was widely used in industry. The Ni-P alloy coating is of fine corrosion-proof, containing 10-30g nickel sulfate, 20-40g sodium hypophosphite, 5-20g sodium acetate, 12-60g complexing agent and 0.002-0.01g complex stabilizer, with pH value of 4.5-5.0.
TL;DR: The work in this article summarizes the research conducted in our laboratory over the past five years, with a focus on the reactions of hypophosphorous acid derivatives, including room-temperature radical addition and palladium-catalyzed addition.
Abstract: This account summarizes the research conducted in our laboratory over the past five years. New methodologies were devised for the formation of P–C bonds with a focus on the reactions of hypophosphorous acid derivatives. Three types of reactions have been developed: palladium-catalyzed cross-coupling, room-temperature radical addition, and palladium-catalyzed addition. Our results are summarized in each of these areas and include some of our most recent data. (1) Our palladium-catalyzed cross-coupling has been extended to the direct coupling of alkyl phosphinates with a variety of aryl, heteroaryl, and even alkenyl electrophiles. (2) The addition of sodium hypophosphite under radical conditions is extended from alkenes to alkynes. (3) The catalytic addition of hypophosphorous compounds using palladium catalysts (hydrophosphinylation) is also discussed.
Patent•
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21 Jul 2005
TL;DR: In this article, a polyamide 66 film consisting of at least one phosphorus compound selected from sodium phosphate, sodium phosphite or sodium hypophosphite, (C) sodium alminate, (D) hindered phenol antioxidant, and (E) a higher fatty acidamide, and has ≤40 ppm sodium metal element concentration.
Abstract: PROBLEM TO BE SOLVED: To prepare a polyamide 66 film excellent in heat resistance, and also in hue, gel strength, and the like. SOLUTION: This polyamide 66 film consists of (A) the polyamide 66, (B) at least one phosphorus compound selected from sodium phosphate, sodium phosphite or sodium hypophosphite, (C) sodium alminate, (D) a hindered phenol antioxidant, and (E) a higher fatty acidamide, and has ≤40 ppm sodium metal element concentration. COPYRIGHT: (C)2005,JPO&NCIPI
Journal Article•
TL;DR: In this article, a variety of sulphoxides using sodium hypophosphite under microwave irradiation is described, which avoids the use of solvent and is applicable for the variety of substrates.
Abstract: Reduction of a variety of sulphoxides using sodium hypophosphite under microwave irradiation is described. The method avoids the use of solvent and applicable for the variety of substrates.
Patent•
05 Jan 2005
TL;DR: The active zirconium white pigment has suspending property, hydrophobic property, UV resistance, X-ray and high-low temperature resistance, wearability, acid resistance and other excellent properties, applied to act as coating, protective glasses, color TV set glass screens, wearable parts, etc as discussed by the authors.
Abstract: The invention relates to an active zirconium white pigment preparing method, including such steps as a, selecting one or two of the zirconium oxide and zirconium silicate as basal material, adding in aid-grinding agent sodium carbonate and water, and grinding by a blending ball mill; b, fulling, eliminating irons by magnetic filtering and press-filtering to dehydrate; c, adding sodium hypophosphite and stabilizer magnesium oxide in material cake, and mixing uniformly into a mixture; d, high-temperature burning; e, chemical coating processing; f, after-processing. The active zirconium white pigment has suspending property, hydrophobic property, UV resistance, X-ray and high-low temperature resistance, wearability, acid resistance and other excellent properties, applied to act as coating, protective glasses, color TV set glass screens, wearable parts, etc.
01 Jan 2005
TL;DR: In this article, an autocatalytic deposition of Ni-Zn(Fe)-P alloys has been carried out on substrate of carbon steel from a bath containing nickel sulfate, zinc sulfates, sodium hypophosphite, sodium citrate and boric acid.
Abstract: The autocatalytic deposition of Ni-Zn(Fe)-P alloys has been carried out on substrate of carbon steel from a bath containing nickel sulfate, zinc sulfate, sodium hypophosphite, sodium citrate and boric acid. The effects of pH and the molar ratio of NiSO4/ZnSO4 on the deposition rate and the composition of deposits have been studied. It was found that the presence of zinc sulfate in the bath has an inhibitory effect on the alloy deposition. The structure and the surface morphology of Ni-Zn(Fe)-P coatings were characterized with XRD and SEM, respectively. The alloys plated under the experimental conditions consisted of an amorphous phase coexisting with a crystalline cubic Ni phase(poly-crystalline). The surface morphology of the coating is dependent on the deposition parameters. The corrosion resistance of the Ni-Zn(Fe)-P deposits was examined via mass loss tests and anodic polarization measurements, respectively. The results show that the surface morphologies of the deposits and the corrosion resistance of the deposits have been improved. The results of mass loss tests almost accord with those of anodic polarization measurements. The corrosion mechanisms of Ni-Zn(Fe)-P alloys in NaCl and NaOH solutions were investigated by means of EDX. The deposit immersed in an NaCl or an NaOH solution contains more content of oxygen and less contents of the metals(except Fe) than that placed in air, which shows that the NaCl or NaOH solution can accelerate the oxidation of the deposit.
Patent•
16 Feb 2005
TL;DR: In this article, a kind of directions for producing chemic platting liquid of Magnesium and its alloy for the area of treating with the surface of metallic material was proposed for the purpose of making chemic plating liquid.
Abstract: A kind of directions for producing chemic platting liquid of Magnesium and its alloy for the area of treating with the surface of metallic material. This invention's compositions and their weight perception are: nickel chloride: 2.0-5.5%, citric acid: 1-3%, fluoride: 2-6%, sodium hypophosphite: 1.5-4.5%, sulphur urea: 0.00005-0.00015%, sodium dodecanesulphonate : 0.01-0.05%, the other's water. Compared with existing technology, this invention's advantage lies in using nickel chloride replacing nickel subcarbonate as nickel salt when producing chemical platting solution. This reduces greatly the cost of magnesium alloy chemic platting and process of making platting liquid is easier. The produced platting layer using this method can be used as individual protection layer for magnesium and magnesium alloy and also as floor of the regular platting layer.
Patent•
30 Nov 2005
TL;DR: In this article, a method for coating nickel-phosphor-carbon-oxygen alloy by chemical recombination coating and the Ni-P-C-O alloy coating prepared with the chemical composite liquid, adding optimization promoter, complex builder, buffer and brightener into the solution of nickel sulfate and sodium hypophosphite.
Abstract: The invention is a method for coating nickel-phosphor-carbon-oxygen alloy by chemical recombination coating and the Ni-P-C-O alloy coating prepared with the chemical composite liquid, adding optimization promoter, complex builder, buffer and brightener into the solution of nickel sulfate and sodium hypophosphite to prepare Ni-P-C-O composite liquid, preparing Ni-P-C-O alloy composite deposit with the composite liquid It does not need to add solid particle into coating liquid while it does in general chemical recombination coating, and the coating liquid is steady, usage life long, easy to maintain, fit to industrial production, the crystallization of coating deposit fine and close, the rigidity high, especially having a property of corrosion prevention
Patent•
17 Aug 2005
TL;DR: The process of preparing high density nanometer metal material includes first chemical deposition to prepare non-crystalline state metal material of Ni or Ni-base alloy and the subsequent stepped heat treatment for crystallizing as discussed by the authors.
Abstract: The process of preparing high density nanometer metal material includes first chemical deposition to prepare non-crystalline state metal material of Ni or Ni-base alloy and the subsequent stepped heat treatment for crystallizing. The preparation of non-crystalline state metal material of Ni or Ni-base alloy includes the steps of: 1) compounding chemical deposition solution with nickel sulfate, sodium hypophosphite, sodium acetate, succinic acid, potassium iodide, lead acetate, thiourea and water; and 2) heating the chemical deposition solution to 75-95 deg.c, and setting the substrate material, carbon steel or aluminum, inside the solution to form non-crystalline state metal Ni or Ni-base alloy in the surface of the substrate material. The prepared nanometer metal material may be 2D film or 3D lump of nanometer crystal grains controlled in 5-200 nm and has high density, no crystal interface contamination and homogeneous crystal grains in relaxation state.