Showing papers on "Sodium sulfite published in 2011"

Sodium and Potassium Released from Burning Particles of Brown Coal and Pine Wood in a Laminar Premixed Methane Flame Using Quantitative Laser-Induced Breakdown Spectroscopy:

Abstract: A quantitative point measurement of total sodium ([Na](total)) and potassium ([K](total)) in the plume of a burning particle of Australian Loy Yang brown coal (23 ± 3 mg) and of pine wood pellets (63 ± 3 mg) was performed using laser-induced breakdown spectroscopy (LIBS) in a laminar premixed methane flame at equivalence ratios ( U ) of 1.149 and 1.336. Calibration was performed using atomic sodium or potassium generated by evaporation of droplets of sodium sulfite (Na(2)SO(3)) or potassium sulfate (K(2)SO(4)) solutions seeded into the flame. The calibration compensated for the absorption by atomic alkalis in the seeded flame, which is significant at high concentrations of solution. This allowed quantitative measurements of sodium (Na) and potassium (K) released into the flame during the three phases of combustion, namely devolatilization, char, and ash cooking. The [Na](total) in the plume released from the combustion of pine wood pellets during the devolatilization was found to reach up to 13 ppm. The maximum concentration of total sodium ([Na](max)M(total)) and potassium ([K](max)(total)) released during the char phase of burning coal particles for φ = 1.149 was found to be 9.27 and 5.90 ppm, respectively. The [Na](max)(total) and [K](max)(total) released during the char phase of burning wood particles for φ = 1.149 was found to be 15.1 and 45.3 ppm, respectively. For the case of φ = 1.336, the [Na](max)(total) and [K](max)(total) were found to be 13.9 and 6.67 ppm during the char phase from burning coal particles, respectively, and 21.1 and 39.7 ppm, respectively, from burning wood particles. The concentration of alkali species was higher during the ash phase. The limit of detection (LOD) of sodium and potassium with LIBS in the present arrangement was estimated to be 29 and 72 ppb, respectively.

Temperature-resistant salt-resistant efficient gel, and preparation and use thereof

Abstract: The present invention discloses a temperature resistant salt tolerant high efficiency gel and a preparation method and application thereof. The preparation method is characterized in that the preparation method comprises the following steps: preparing a comb-shaped associated copolymer PAH containing macromonomers and functional hydrophobic monomers into an aqueous solution having the concentration of 0.1 to 4g/L, the crosslinking agent concentration of 0.01 to 1.0g/L, the surfactant concentration of 0.01 to 8mmol/L and the sodium sulfite thermal stabilizer concentration of 0.005 to 1.0g/L; adding the aqueous solution into a mixing container with a stirring device; stirring the aqueous solution evenly at the room temperature; regulating the pH value of the solution to be equal to between 4 and 11, and obtaining a temperature resistant salt tolerant high efficiency gel polymer solution system used for tertiary oil recovery and scavenge, displacement modification, profile modification or water shutoff. The polymer solution system has micro-crosslinking to form the gel during the flowage inside the oil reservoir. The gel has good elasticity, not easy dehydration, stable gelling performance, and excellent tackification, temperature resistance, salt tolerance, shearing resistance and ageing resistance.

Sodium sulfite is a potential hypoxia inducer that mimics hypoxic stress in Caenorhabditis elegans

Abstract: Physical and chemical hypoxia have been widely used in the study of hypoxic injury; however, both of these hypoxia models have their own limitations. Physical hypoxia is usually difficult to control and maintain. Chemical hypoxia, which is usually induced by chemical hypoxia-mimicking agents, such as CoCl2, may result in heavy metal toxicity or impose security threats. To develop a more suitable hypoxia model, we focused on sodium sulfite (Na2SO3) and evaluated its ability to remove dissolved oxygen in aqueous solutions. Our results showed that sodium sulfite successfully induced hypoxic conditions. The degree of hypoxia and the guarantee period of the sodium sulfite solution could be easily controlled by the concentration of soluble sodium sulfite. In addition, we used sodium sulfite to create a hypoxia model in Caenorhabditis elegans. Similar to physical hypoxia, the sodium sulfite solutions induced hypoxia-related death in the worms and led to morphologic cell defects and C. elegans hypoxia inducible factor 1 stabilization. Taken together, our data show that sodium sulfite is a potential hypoxia inducer that mimics hypoxic stress in C. elegans.

Method for accelerating monopersulfate and persulfate to produce free sulfate radicals

Abstract: The invention relates to a method for accelerating monopersulfate and persulfate to produce free sulfate radicals, belonging to the field of water treatment Accelerating agents are used based on a method that an accelerated chemical agent and an accelerating agent of a monopersulfate and persulfate system are added into a water body to be treated, and the water body is uniformly stirred to react The accelerating agent comprises ascorbic acid, sodium sulfite, hydroxylamine hydrochloride, hydroxylamine sulfate, O-cyclopropyl methyl hydroxylamine, potassium permanganate, ammonium chloride, citric acid and the like The method benefits the acceleration of the reaction rate of water treatment and the reduction of cost; in the method, the pH value of the water body is not needed to be adjusted to be lower than 4, and subsequent water treatment can be carried out without adjusting the pH value of the water body to be neutral after the reaction of monopersulfate and persulfate The method is applied to the fields of organic waste water, underground water, surface water and drinking water

Benification combined method of polymetallic sulphide ore containing copper, lead, zinc and tin

Abstract: The invention relates to a beneficiation method, in particular to a beneficiation method for separating the polymetallic sulphide ore containing copper, lead, zinc and tin. The method comprises the following steps: (1) carrying out ore grinding on the raw ore before carrying out bulk flotation on copper, lead and sulphur, using diethyl mixed with xanthate as collecting agent of copper and lead mineral, using zinc sulphate and sodium sulfite as inhibitor of zinc mineral; (2) carrying out phase-2 ore grinding and selection; (3) separating copper, lead and sulphur, using sodium sulfite and sodium thiosulfate as the inhibitor of the lead and sulphur mineral, using Z-200 as collecting agent for separation and scavenging and then carrying out lead flotation after the separation and scavenging; (4) carrying out zin flotation on the bulk flotation tailings; and (5) finally, carrying out reselection on the zinc flotation tailings to recover tin. The metalliferous mineral of the invention has the advantages of good separating effect, high metal recovery rate, more complete comprehensive recovery of useful minerals, low cost of medicament, simple method, easy operation and energy conservation.

Phase Diagrams for Aqueous Two-Phase Systems Containing the 1-Ethyl-3-methylimidazolium Tetrafluoroborate/1-Propyl-3-methylimidazolium Tetrafluoroborate and Trisodium Phosphate/Sodium Sulfite/Sodium Dihydrogen Phosphate at 298.15 K: Experiment and Correlation

Abstract: Liquid–liquid equilibrium data have been determined for 1-ethyl-3-methylimidazolium tetrafluoroborate ([Emim]BF4)/1-propyl-3-methylimidazolium tetrafluoroborate ([Pmim]BF4) + trisodium phosphate (Na3PO4)/sodium sulfite (Na2SO3)/sodium dihydrogen phosphate (NaH2PO4) aqueous two-phase systems at T = 298.15 K, respectively. Two empirical equations were used to correlate binodal data. The Othmer-Tobias and Bancroft as well as Setschenow-type equations were used to correlate the tie-line data. The results show that good agreement was obtained with the experimental data. The effect of salt on the phase forming ability has been studied based on the effective excluded volume (EEV) values from fitting the binodal data to the binodal model. The binodal curves and EEV both indicate that the salting-out effect of the three salts follow the order Na3PO4 > Na2SO3 > NaH2PO4, which can also be related to the Gibbs free energy of hydration of the ions (ΔhydG) and [Pmim]BF4 is easier to be excluded the IL-rich phase than [...

Method for recycling sodium formate and sodium sulfite from waste sodium hydrosulfite liquid with sodium formate method

Abstract: The invention relates to a method for recycling sodium formate and sodium sulfite from waste sodium hydrosulfite liquid with a sodium formate method. The method comprises the following steps of: carrying out precise filtration and ultrafiltration on waste sodium hydrosulfite liquid with the sodium formate method to remove insoluble substances and granular impurities in the liquid; and then introducing the liquid into a nanofiltration device for nanofiltration separation, wherein after being evaporated and concentrated, an obtained nanofiltration permeate solution can be used as a raw material of the sodium hydrosulfite and returned to a sodium hydrosulfite production station, and can also be continuously evaporated, concentrated, crystallized, centrifuged and filtered to obtain a sodium formate product of which the purity is higher than 95 percent; and an obtained nanofiltration concentrated solution can be introduced into an evaporator for concentrating and then is crystallized, centrifuged and filtered to obtain a crude sodium sulfite product. The method has the technical advantages of no secondary pollution, high purity of the sodium formate, simple process and easiness for industrial realization, wherein the purity can be up to higher than 95 percent.

Two-compartment method for determination of the oxygen transfer rate with electrochemical sensors based on sulfite oxidation.

Abstract: The dissolved oxygen concentration is a crucial parameter in aerobic bioprocesses due to the low solubility of oxygen in water. The present study describes a new method for determining the oxygen transfer rate (OTR) in shaken-culture systems based on the sodium sulfite method in combination with an electrochemical oxygen sensor. The method replaces the laborious titration of the remaining sulfite by an on-line detection of the end point of the reaction. This method is a two-step procedure that can be applied in arbitrary flasks that do not allow the insertion of electrodes. The method does not therefore depend on the type of vessel in which the OTR is detected. The concept is demonstrated by determination of the OTR for standard baffled 1-L shake flasks and for opaque Ultra Yield™ flasks. Under typical shaking conditions, k(L) a values in the standard baffled flasks reached values up to 220 h(-1) , whereas the k(L) a values of the Ultra Yield flasks were significantly higher (up to 422 h(-1) ).

Soda wet desulphurization process and system for sintering flue gas

Abstract: The invention discloses a soda wet desulphurization process and a soda wet desulphurization system for sintering flue gas, and solves the problems of severe pollution and the like in the prior art. Sodium carbonate serves as a desulfurizing agent, and a desulfurization by-product is sodium sulfite; and the process comprises the following steps of: (1) cooling and introducing sulfur-containing flue gas into a desulfurizing tower; and (2) purifying the sulfur-containing flue gas in the step (1) in the desulfurizing tower by taking solution of sodium carbonate or sodium hydroxide as an absorbent, demisting the purified flue gas through a demister and discharging. The process is simple in procedures, high in desulphurization efficiency, high in response speed and high in value of the desulfurization by-product, and saves energy and land.

Dyeing defect renovation agent and method for preparing the same

Abstract: The invention relates to a dyeing defect repair agent and a preparation method thereof. The dyeing defect repair agent comprises a color stripping agent and a color stripping catalyst and is characterized in that the ingredients of the color stripping agent based on weight percent comprise: 80-95% of an organic reducing agent which is zinc formaldehyde sulfoxylate (Decrolin), thiourea dioxide or leucotrope W; 20-5% of an inorganic reducing agent which is sodium thiosulfate, sodium bisulfite or sodium sulfite; the ingredients of the color stripping catalyst based on weight percent comprise: 5-10% of alkaline compounds which are organic bases comprising triethanolamine or which are inorganic bases comprising sodium carbonate, sodium hydroxide, potassium carbonate or sodium silicate; and soft water as the balance. The preparation method thereof employs the following procedures: preparing the color stripping agent: wherein, the organic reducing agent and the inorganic reducing agent basedon the weight percentage are sufficiently and uniformly mixed under the room temperature; preparing the color stripping catalyst: wherein, the alkaline compounds based on the weight percent are dissolved and uniformly mixed by using the soft water under the room temperature.

Sulfonated acetone-formaldehyde high-efficiency water reducing agent modified by enzymatic hydrolysis lignin or by derivatives thereof, and preparation method thereof

Abstract: The invention provides a sulfonated acetone-formaldehyde high-efficiency water reducing agent modified by enzymatic hydrolysis lignin or by derivatives thereof, and a preparation method thereof, raw materials comprise the enzymatic hydrolysis lignin or the derivatives thereof, acetone, aldehyde, sodium sulfite and sodium metabisulfite, a base catalyst and an acid regulator; the preparation steps comprise: mixing the sodium sulfite, the sodium metabisulfite with the water, heating at constant temperature and agitating, dropwise adding the acetone, adding the enzymatic hydrolysis lignin or the derivatives thereof, regulating pH value by the base catalyst, dropwise adding the aldehyde, continuous reacting for 3 hours, and adding the acid regulator to regulate the pH so as to result in product. The invention sufficiently utilizes reproducible biological resources, which not only solves the defect of low water reducing efficiency of the lignin-sulphonate water reducing agent extracted frompapermaking 'black liquor' in the prior art, but also can replace partial petrochemical raw materials and reduce the production cost of the high-efficiency water reducing agent; the enzymatic hydrolysis lignin- or the derivatives thereof-modified high-efficiency water reducing agent has great use effect.

Synthesis and Characterization of Sodium Nonylphenol Ethoxylate(10) Sulfoitaconate Esters

Abstract: Two sodium nonylphenol ethoxylate(10) sulfoitaconate ester surfactants, namely disodium nonylphenol ethoxylate(10) sulfoitaconate monoester (DNE(10)SIM) and sodium nonylphenol ethoxylate(10) sulfoitaconate diester (SNE(10)SID), were synthesized through the esterification and sulfonation reactions with nonylphenol ethoxylate(10) ester, itaconic acid and sodium sulfite as the raw materials. The chemical structures of the prepared surfactants were confirmed by FTIR and 1H NMR. The surface tension of the synthesized surfactants was measured at 25 °C and the surface active properties were characterized. The DNE(10)SIM had better surface activity. The CMC was 1.77 × 10−6 mol L−1 and γCMC was 35.45 mN m−1. The CMC and γCMC for the SNE(10)SID were 5.42 × 10−5 mol L−1 and 37.67 mN m−1, respectively. Moreover, the emulsification power of SNE(10)SID was better.

Technical method for removing sulfur dioxide in flue gas by using sodium sulfite and equipment thereof

Abstract: The invention discloses a technical method for removing sulfur dioxide in flue gas by using sodium sulfite and equipment thereof. The method comprises: purification treatment and desulfuration of soot, pyrolysis of sodium bisulfite, separation and electrolysis of sulphate, and tertiary desulfuration carried out in a thionizer having an upper, a middle and a lower absorption sections by taking sodium sulfite solution as desulfurizer; the invention also provides processing equipment used for removing sulfur dioxide in flue gas by using sodium sulfite. The purification treatment can be carried out on the flue gas before entering the thionizer by the processing equipment, so that the sulfur dioxide in the flue gas can be well absorbed, the sulfur dioxide in the flue gas can be avoided polluting the air, chloride and dust are prevented from affecting the desulfuration system, and the sulphate in the desulfurizer can be continuously separated. The desulfurizer has good desulfuration effect and less consumption, so that the project cost and the power consumption are both low, and the recovered sulfur dioxide can be used for producing sulphuric acid having high quality. Therefore, the invention has remarkable economic and social benefits.

Ethylene glycol bi-sulpho succinic acid bi(2-methyl amyl) artesunate and production method thereof

Abstract: The invention discloses an ethylene glycol bi-sulpho succinic acid bi(2-methyl amyl) artesunate and a production method thereof. The product is prepared by reacting maleic anhydride with 2-methyl-1-amyl alcohol to form a monoesterfication product, reacting the monoesterfication output with sodium sulfite to form a sulphonated product, and then reacting the sulphonated product with ethylene glycol. The product has good performance and is simple to synthesize.

P-hydroxybenzene glycine synthesis technology

Abstract: The invention belongs to the field of pharmaceutical chemical engineering intermediate production, which relates to a synthesis technology of p-hydroxyphenylglycine (HPG) The purpose of the invention is achieved by the following steps: phenol, glyoxylic acid, water and sulfamic acid carry out the one-pot braise reaction under the action of catalysts such as benzene sulfonic acid, p-toluenesulfonic acid, o-toluenesulfonic acid, and the like; after the reaction is finished, a small amount of reducing substances such as sodium sulfite, sodium bisulfite, hydroxylamine hydrochloride, and the like, are added; finally, the PH value is adjusted by alkali, the mother liquor separation is washed by large amount of water and then washed by organic solvents such as methanol, ethanol, acetone, glacial acetic acid, and the like; the obtained product HPG is white powder, wherein, the content of NPLC is equal to or more than 985, which can meet the requirement of splitting The method has the advantages of low production cost, simple operation, stable quality, etc

Enzymatic method for extracting soy peptide

Abstract: The invention discloses an enzymatic method for extracting a soy peptide In the method, the soy peptide is obtained by using soybean protein powder as a main raw material through the steps of: distributing water, adding alcohol and sodium sulfite, heating, boiling, filtering, adding protease into a filtrate for enzymolysis, inactivating enzyme, decoloring, separating membrane, and drying the obtained filtrate The method has the advantages of short production cycle, low cost and no generation of toxic and harmful substances, and can be widely applied to the fields of foods, medicines, health care products, biosynthesis, and the like; and the obtained products has high safety

Method for improving tungsten-base gold-plating bond strength

Abstract: The invention relates to a method for improving the gold-plating bond strength of a tungsten metal surface, and belongs to the field of the surface modification of metal materials. In the method, the problems of dropping and delamination of plated gold on surfaces of tungsten materials are solved. The method comprises the following steps of: removing oxides on the surface of a tungsten spiral line before electroplating; electroplating copper at the temperature of between 20 and 60 DEG C and under a condition that the pH value is between 0.6 and 1.2 and a condition that the current density is between 0.1 and 0.3 A/dm for 15 to 120 seconds, wherein copper layer electroplate liquid comprises 170 to 210 g/L of anhydrous cupric sulfate, 35 to 60 g/L of sulfuric acid and the balance of water, and the pH value is regulated by the sulfuric acid and sodium hydroxide; and electroplating the gold at the temperature of between 20 and 35 DEG C under a condition that the pH value is between 8 and 11 and a condition that the current density is between 0.4 and 0.6 A/dm for 150 to 300 seconds, wherein gold-plating liquid comprises 5 to 8 g/L of gold sodium sulfite, 30 to 40 g/L of anhydrous sodium sulfite and the balance of water, and the pH value is regulated by the sulfuric acid and the sodium hydroxide. In the method, gold-plating samples are subjected to heat treatment in a hydrogen furnace at the temperature of between 950 and 1,000 DEG C for 30 minutes, and gold-plating layers are not dropped.

Peculiarities of cathodic reduction of gold from sulfite-thiocarbamide electrolytes

Abstract: The cathodic reduction of gold from mixed sulfite-thiocarbamide electrolytes is studied as a function of the electrolyte composition. In the absence of thiocarbamide in the gold-plating sulfite solutions, gold is deposited at the cathode at high overpotentials. The equilibrium composition of the electrolyte is calculated at various ratios between the amounts of sulfite and thiocarbamide; it is shown that an addition of 10−5 to 0.5 M thiocarbamide does not change considerably the solution composition, and gold ions are present, predominantly, in the form of the complex with sulfite ions. However, an addition of thiocarbamide to the solution leads to a decrease in the overpotential of metal deposition by approximately 0.5 V. A possible mechanism of the catalytic effect of thiocarbamide on the cathodic reduction of gold from mixed sulfite-thiocarbamide electrolytes is proposed. It is shown that sulfite ions have a stabilizing effect on the decomposition of thiocarbamide in the alkaline solutions.

Sodium sulfite: A promising reagent in the electrochemical oxidation of metallic silver

Abstract: Among the complexing agents suitable for the electrochemical silver recovery, a promising one is sodium sulfite forming silver complexes with high stability constants: according to our data, log β1 ~ 5.3, log β2 ~ 8.2. This reagent is accessible and cheap, but nevertheless it almost never has been used for these purposes. We studied the stability of the sodium sulfite solutions in air and showed a possibility of using them for a long period. Using the methods of potentiodynamic polarization and potentiostatic electrolysis, we have studied characteristics of the process of metallic silver oxidation in the sulfite media. The anodic polarization process of the silver dissolution is shown to occur with 100% yield with respect to the consumed current. Simultaneously, on the cathode deposited up to 90% of dissolved silver. An urgent problem of chemical technology is the extraction of noble metals, particularly silver, from the electronic and jewelry scrap and similar sources. The traditional methods of the silver extraction (1-3) are based on its dissolution in the presence of oxidants in acid solution (perchloric acid, sulfuric acid, nitric acid) or complexing agents (cyanide, thiocyanate, thiourea). From these solutions, silver is isolated as insoluble salts or is reduced to metal. The main disadvantages of these techniques are the high consumption of reagents and non-selectivity of dissolution: besides silver copper, iron, and other components of the raw material are dissolved. Significantly less expensive are the methods that use electrolytic anodic oxidation of silver in specially selected electrolytes (4). Processing a material containing large amount of basic metals (copper, iron, nickel, etc.) should be performed under conditions providing selective transfer of silver in the solution. For this purpose are used the electrolytes containing thiourea (5), thiocyanate (6, 7), amino acids (8), etc. Silver can be deposited and isolated on the cell cathode. Note that the earlier proposed thiourea me- dium (2) still is widely used in the gold and silver hydrometallurgy. The study of the process of elec- trolytic oxidation and reduction of silver has been carried out in (9-11). A promising complexing agent in the processes of electrochemical oxidation of silver is sodium sulfite, the side product in processing of sulfide ores used in the manufacture of chemicals. The stability of the

Nutrient liquid medium for culturing plague microbe of vaccine strain eb

Abstract: FIELD: medicine. ^ SUBSTANCE: nutrient medium contains enzymeatic hydrolyzate of beef meat, sodium chloride, sodium phosphate bisubstituted, sodium sulfite, Karpuzidi stimulant and purified water in specified component ratio. ^ EFFECT: invention makes it possible to obtain quality nutrient medium for culturing microbial cells of plague microbe of vaccine strain EB in sufficient quantity during 48 h. ^ 1 tbl, 3 ex

Purification treatment method of low concentration formaldehyde waste gas

Abstract: The invention relates to a method for purifying the low-concentrating formaldehyde waste gas. In the method, a biomembrane reactor is adopted to subject the gas phase of the formaldehyde waste gas to the biochemical degradation purification, and subject formaldehyde dissolving into a circulation liquid to the chemical absorption reaction purification. The chemical absorption reaction purificationis carried out by adding sodium sulfite with the molar concentration of 0.01 to 0.1 M into the biomembrane reactor circulation liquid, and subjecting formaldehyde into the liquid phase to the chemical absorption purification. By adopting the method, the gas phase biochemical degradation purification and the liquid phase chemical absorption purification can be simultaneously carried out in the biomembrane reactor; the purification efficiency of the reactor to the formaldehyde waste gas is higher than 90%; and the unit volume load of the reactor is higher than 20 mg/L*h and is improved by more than 80% compared with that of the reactor without sodium sulfite added into the reaction circulation liquid. The method can prevent secondary pollution and reduce the device cost and the operation cost while enhancing the effect of the biomembrane reactor for purifying the formaldehyde waste gas.

Method for purifying lateritic nickel ore leach liquor

Abstract: The invention discloses a method for purifying lateritic nickel ore leach liquor, which comprises the following steps: neutralizing lateritic nickel ore leach liquor with lime milk or lime powder to remove iron; after carrying out solid-liquid separation, neutralizing with sodium hydroxide solution until the pH value reaches 7.5-8.5, thereby precipitating nickel, wherein magnesium stays in the solution to be separated from nickel; dissolving nickelous hydroxide with sulfuric acid, adding sodium sulfite and barium carbonate, and regulating the pH value of the nickel sulfate solution to 2.0-2.5; simultaneously adding the obtained nickel sulfate solution and sodium hydroxide solution into a stirring tank, wherein the pH value of the solution in the stirring tank is kept at 5.0-6.0 by controlling the addition amount of the sodium hydroxide solution; and carrying out solid-liquid separation on slurry obtained after reaction, wherein the obtained nickel sulfate solution can be sent to a treatment procedure for further extracting nickel. Compared with a common process, the method disclosed by the invention has obvious advantages in the aspects of removing impurities in lateritic nickel ore leach liquor and increasing filtering rate of slurry.

Synthesis of Fe-Co Nanobars Using Sodium Sulfite Assisted Polyol Process and their Structural and Magnetic Studies

Abstract: We report the synthesis of soft magnetic Fe-Co nanobars by an improved polyol process using cetyltrimethylammonium bromide (CTAB) as stabilizer. The synthesized samples were studied by using Transmission Electron Microscopy. The Fe-Co nanoparticles were characterized by X-ray diffraction, UV-Vis spectroscopy, Fourier transform infrared spectroscopy and Vibrating Sample Magnetometer. The Fe-Co nanobars showed prominent UV-VIS absorption at 371 nm. This report discusses the effect of sodium sulfite and CTAB on the synthesis of Fe-Co nanoparticles.

Photolysis of p-benzoquinone and p-chloranil in aqueous sodium sulfite solution

Abstract: Photosubstitution of the sulfo group for hydrogen (chlorine in chloranil) is observed under irradiation of sulfonated derivatives of hydroquinone formed upon dissolving of p-benzoquinone and p-chloranil in aqueous solutions of sodium sulfite. The quantum yield of the photochemical reaction is 0.18 ± 0.02 for p-benzoquinone. The rate constant of the thermal reaction of substitution is 5.5 × 10−4 l mol−1 s−1. The substitution reaction is sensitized by eosin upon irradiation with visible light. During the course of irradiation of sulfohydroquinones, the formation of a product with an absorption maximum at 235 nm was found. The product decays with a rate constant of 0.005 s−1.

Cyanide-free gold electroplating liquid

Abstract: The invention relates to cyanide-free gold electroplating liquid, and belongs to the field of surface modification of metal materials. The cyanide-free gold electroplating liquid has the advantages that: the electroplating liquid is non-toxic, simple in a formula and high in stability, does not have the phenomenon of turbidity and color change after being stood at normal temperature and still can be used. The cyanide-free gold electroplating liquid comprises the following main ingredients: gold trichloride, sodium sulfite or potassium sulfite serving as a main complexing agent, ethylene diamine tetraacetic acid (EDTA) or sodium citrate serving as an auxiliary complexing agent and sodium chloride or potassium chloride serving as inorganic salt. In the cyanide-free gold electroplating liquid, a new formula proportion is adopted, the cost is low, a plating layer is high in bonding force and bright, and the preparation of the functional gold plating layer is realized. The popularization and application of the cyanide-free gold electroplating liquid can create economic and social benefit.