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2019-07-26 10:44:21
If the formula design of cosmetics is defective, it may cause abnormal skin reaction in the use process, and then affect people's mood or health to a certain extent. Therefore, the raw materials for cosmetics production can not have immune rejection reaction with human body, that is, they must be non-irritating and non-toxic to skin, hair, eye film, and have good appearance, skin feeling, good smearing and stretchability.
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2019-07-24 16:19:50
Some surfactants with corrosion inhibition properties are commonly used in weak acidic and neutral solutions, especially in oily sewage where the metal corrosion resistance is usually based on lipophilic surfactants. Surfactants with corrosion inhibition can form adsorption film on metal surface. XPS energy spectrum analysis and electrochemical impedance spectroscopy of metal electrode surface in corrosion medium containing surfactants can prove that surfactants act as corrosion inhibitors through geometric coverage effect.
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2019-07-21 18:46:23
At present, chemical flooding is the main method of tertiary oil recovery in China. Surfactants are suitable for chemical flooding. On the basis of practical work experience, many experts and scholars have put forward the following requirements for surfactant in oilfields:
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2019-07-18 13:59:17
The carbon-carbon single bond of polymer surfactants can rotate freely under general conditions. The bond angle of the carbon-carbon single bond of the main bond is approximately 109 28', and the degree of polymerization is generally large, that is, the main chain is quite long. Therefore, in the medium, the main chain is not straight, twenty-bending and curling. Curled linear molecules with multiple negative charges are adsorbed by solid particles at several parts of the molecular main chain, as if bridging between these solid particles. This process of relatively aggregating solid particles is called the adsorption bridging between polymer flocculants and solids. _
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2019-07-15 10:00:51
In the past two years, the Ministry of Science and Technology, two major oil companies, PetroChina and Sinopec have organized a series of research projects on surfactant mixing, organized a series of research projects in large oil fields, scientific research institutes and universities, and achieved some basic research results. In the surfactant flooding systems of Zhongyuan Oilfield, Changqing Oilfield, Dagang Oilfield and Yanchang Oilfield, several low permeability reservoirs have been selected for field tests, and the effect of enhancing oil recovery is obvious. In Zhongyuan Oilfield, the study on the oil displacement efficiency of composite surfactant shows that the oil displacement efficiency in formation water is 7.68% higher than that in petroleum sulfonate. Shengli Oilfield has developed a low-cost composite surfactant for oil displacement in Zhuangxi high-temperature, medium-low permeability reservoir. The exploratory application test of this surfactant was carried out in Zhuangzhuang 50 well group No. 5 in 2006. As of May 2007, 6 wells in this group have increased oil production by 1656 tons. Chinese style
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2019-07-12 13:31:19
On this basis, a series of new surfactants have been successfully developed, such as alkyl polyglycosides (APG) and gluconamide (APA), which are produced by the reaction of glucose and lipids with alcohols or fatty acids, and ED3A, which has both surface activity and strong complexation ability with calcium and magnesium ions, obtained by EDTA modification. Hexadecyl diphenyl ether monosulfonate (C16MADS); GEMINI surfactant; crackable, reactive biosurfactants, etc.
But these surfactants are not widely used in leather industry. It has been reported that alkyl polyglycerol (APG) and other surfactants (such as JFC, etc.) have been used as leather soaking aids, leather degreasing agents, retanning fillers, fatliquoring softeners and dyeing and oiling aids. The application of this kind of material in leather production is beneficial to environmental protection and ecology.
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2019-07-09 19:28:54
Surfactants for oil displacement can be divided into non-ionic and ionic types. In order to enhance the performance of surfactants, scientists have studied a series of new surfactants, such as non-ionic-anionic surfactants, fluorine surfactants, Gemini surfactants, biological surfactants and so on. These new surfactants not only have good surface activity, but also have the properties of temperature resistance and salt resistance. At present, surfactants still have some problems, such as complex synthesis process, high cost and insufficient application. In order to solve these problems, it is necessary to improve the molecular structure of surfactants or to mix them with alkali and polymer to become a potential oil displacement method.
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2019-07-06 20:38:19
Silicone rubber is a kind of polymer silicone, it get by controlling the length of the skeleton, and cross-linking of organic groups with skeleton, insulator is made of silicone rubber, next, I will introduce the role of silicone rubber insulator.
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2019-07-06 18:11:28
The environmental protection performance of surfactants mainly refers to the toxicity and biodegradability of surfactants themselves and the improvement of the absorption rate of surfactants to other chemical materials.
On this basis, a series of new surfactants have been successfully developed, such as alkyl polyglycosides (APG) and gluconamide (APA), which are produced by the reaction of glucose and lipids with alcohols or fatty acids, and ED3A, which has both surface activity and strong complexation ability with calcium and magnesium ions, obtained by EDTA modification. Hexadecyl diphenyl ether monosulfonate (C16MADS); GEMINI surfactant; crackable, reactive biosurfactants, etc.
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2019-07-02 13:46:22
In order to improve the performance of electrolyte and the quality of coating, some additives are often added. Surfactants are one of the main kinds of additives. Surfactants have the functions of smoothing, brightening, diffusing, changing the physical properties of coating and inhibiting the escape of acid mist. Surfactants commonly used in electroplating are Ping Jia, OP emulsifier, sodium dodecyl sulfate, sodium methylene bisnaphthalene sulfonate, fluorine surfactant, fatty acid polyethylene oxide ester, polyethylene oxide castor oil, etc.
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2019-06-29 16:06:11
The dilute solution of surfactant obeys the rule of ideal solution. The amount of surfactant adsorbed on the surface of the solution increases with the increase of the concentration of the solution. When the concentration reaches or exceeds a certain value, the amount of adsorbed surfactant no longer increases. These excessive surfactant molecules are disorderly or exist in a regular way in the solution. Practice and theory show that they form associations in solution, which are called micelles.
Surface Pressure of Adsorption Membrane: Surfactant adsorbs at the gas-liquid interface to form an adsorptive film. For example, a frictionless movable floating sheet is placed on the interface to push the adsorptive plasma membrane along the solution surface. The membrane produces pressure on the floating sheet. This pressure is called surface pressure. Surface Viscosity: Like surface pressure, surface viscosity is a property of insoluble molecular membranes.
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2019-06-26 08:50:07
The solubilization of oil contamination by surfactant micelles may be an important mechanism for removing a small amount of liquid contamination from solid surface. Organic substances insoluble in water are added to different parts of micelles to form transparent and stable solutions because of their different properties.
Non-polar oil contamination is added to the non-polar core of micelles, and polar oil contamination is added to the polar group area of the micelle shell according to its polar size and molecular structure, or the polarity of oil contamination molecule is anchored on the surface of micelles, while non-polar hydrocarbon chains are inserted into the core of micelles. Therefore, the solubilization effect of removing oil contamination is actually that oil contamination dissolves in the washing liquid, which makes it impossible for oil contamination to deposit on the surface of the object, and greatly improves the washing effect.
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2019-06-23 08:46:27
The amount of adsorption on the surface increases with the increase of the concentration of the solution. When the concentration reaches or exceeds a certain value, the amount of adsorption does not increase. These excessive surfactant molecules are disorderly or exist in a regular way in the solution. Practice and theory show that they form associations in solution, which are called micelles.
Surfactant molecules are amphiphilic molecules with hydrophilic and lipophilic groups. Water is a strong polar liquid. When surfactant dissolves in water, according to the principle of polarity similarity and polarity difference and repulsion, its hydrophilic group and water are induced to dissolve in water, and its hydrophilic group and water repel and leave water. As a result, surfactant molecules (or ions) are adsorbed on the two-phase interface, which reduces the interfacial tension between the two phases. The more surfactant molecules (or ions) are adsorbed on the interface, the greater the interfacial tension decreases.
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2019-06-20 14:18:46
Surface chemical modification is to finish surface modification by local coating on the surface of inorganic particles by chemical reaction or chemical adsorption between surfactants and inorganic particles.
Liu Qian and other surfactants used polyethylene glycol to treat SiC ultrafine particles. Polyethylene glycol molecular chains were modified on the surface of SiC particles, which acted as a steric barrier to prevent the reunion of solid SiC particles. Surfactant-treated SiC powders with irregular shape or agglomeration can adsorb long molecular chains of surfactants on surface defects and suspended bonds of particles, accelerate the disintegration of large particles or agglomerated particles, and improve the dispersion of SiC particles.
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2019-06-17 11:19:37
According to the characteristics of surfactants, 9 types of surfactants were selected, 7 of them were selected and deinking experiments were carried out with a single surfactant. Five compounds with better effect were selected. The optimum formulation 3 was studied by orthogonal experiment. The optimum technological conditions were A3B2C1D3 with pulp consistency of 9%, deinking agent dosage of 0.8%, deinking temperature of 50 C, deinking time of 50 min and brightness of Newsprint Pulp of 56.1% after deinking.
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2019-06-14 11:04:07
In situ remediation, the use of biosurfactants will have a certain toxicity and impact on the indigenous microbial populations living in them. In addition, their metabolites may be more toxic because they can be degraded by microorganisms. Therefore, the existence of biosurfactants may cause some pollution to the environment and increase the burden of environmental pollution. It can be seen that strengthening the research on the potential impact of biosurfactants on the environment and their biodegradation characteristics will provide an important scientific basis for effectively controlling the environmental pollution caused by biosurfactants and rationally utilizing biosurfactants. In order to ensure the safety of biosurfactants, comprehensive toxicity and environmental hazard experiments of biosurfactants must be carried out in the field of surfactant solubilization and remediation.
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2019-06-11 17:18:47
In solution, surfactant molecules migrate to the surface of solvents, reducing surface tension (water or other solvents). The polar groups of surfactants are directed directly towards the surface of the solvent and hydrocarbon chains are extended into the air. This distribution makes the surface force balance, and consequently the surface tension decreases. The surface tension remained constant after decreasing to the critical micelle concentration, and the surfactant molecules were distributed on the surface of the solvent until the monolayer structure was formed. Surface tension helps to design effective ink. Because the color coating process and these parameters have a great relationship. Many defects in the coloring layer can be attributed to surface tension.
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2019-06-07 09:31:24
When we use chemical products, we must first understand what safety technical requirements it has in order to better ensure personal safety, especially in production, we often use some chemicals or equipment, so we must understand some technical operating guidelines, then take polyether amine as an example, we are simple. Let's get to know.
(1) Technology for preventing accidents of all kinds. For example, in the process of chemical production, fire prevention, explosion proof, safe storage and transportation of chemical dangerous goods, safe use, maintenance, overhaul of pressure vessels and equipment, personal protection, mathematical and statistical analysis of accidents, and safety system engineering, etc.
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2019-06-04 09:24:37
Biodegradation of surfactants is one of the most widely studied methods, and has been adopted by some sewage treatment plants. The method can be roughly divided into activated sludge method, anaerobic digestion method and the method of utilizing soil self-purification. They all use the characteristics of microorganisms that can utilize surfactant as the sole carbon source to complete the degradation of surfactant.
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2019-05-27 17:21:22
In solution, surfactant molecules migrate to the surface of solvents, reducing surface tension (water or other solvents). The polar groups of surfactants are directed directly towards the surface of the solvent and hydrocarbon chains are extended into the air. This distribution makes the surface force balance, and consequently the surface tension decreases. The surface tension remained constant after decreasing to the critical micelle concentration, and the surfactant molecules were distributed on the surface of the solvent until the monolayer structure was formed. Surface tension helps to design effective ink. Because the color coating process and these parameters have a great relationship. Many defects in the coloring layer can be attributed to surface tension.
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