Rotary Film Research Articles

Pharmaceutical development of etodolac transfersomal gel for topical drug delivery system in rheumatoid arthritis

Background: Transferosomes provide delivery of the drug into systemic circulation via the skin as a topical delivery system. So, this study started with the objective of formulating Etodolac transfersomal gel to enhance its skin permeation. Methodology: A total of nine transferosomes (ET-1 to ET-9) containing lecithin, different grades of span and tween, were successfully prepared using a rotary film evaporator. Results and Discussion: After primary evaluation, results were as particle sizes ranged from 222 to 421 nm, zeta potential shows results from –18.50 to –62.53 mV with PDI values 0.254 to 0.303, and the entrapment efficiency (EE%) of Etodolac in the transferosomes ranged from 54.15% to 80.25%. Additionally, the transfersomes formulations were included in carbopol 940 gels (ETC-1 to ETC-9 and EC-0 without transferosomes) and assessed for various characteristics like color, pH, homogeneity, spreadability, viscosity, and in vitro drug release study. Optimized formulation (ET4 and ETC4) underwent further analysis using SEM, TEM, DSC, FTIR, XRD, ex vivo skin permeation, skin irritation and in vivo studies. The in vivo results were compared. % edema inhibition maximum was observed with optimized transfersomal gel formulation (ETC4) as compared to the marketed formulation and plain Carbopol gel when the study was completed after 8 hrs. Conclusion: After this research, it is suggested that Etodolac Transfersomal gel (ETC4) can be considered as an alternate drug carriers system for topical delivery and it could be used to treat Rheumatoid Arthritis

Study on the Performance of Nano-Zinc Oxide/Basalt Fiber Composite Modified Asphalt and Mixture

In order to improve the service quality of roads and resolve the problem of defects in the conventional asphalt pavement in service, this paper uses a 5.3% aluminate coupling agent to modify the surface of nano-ZnO and prepares a composite-modified asphalt with nano-ZnO and basalt fiber (BF) as modifiers. First, the basic performance of different types of asphalt was investigated by means of a rotary film oven experiment. Then, a dynamic shear rheology experiment was carried out to analyze the high-temperature anti-rutting performance of the composite-modified asphalt at different temperatures and frequencies. Then, using a bending creep stiffness test, the low-temperature properties of the composite-modified asphalt were investigated. Finally, the microstructure and modification mechanisms of the composite-modified asphalt were analyzed with scanning electron microscopy and infrared spectroscopy. The results indicate that the anti-aging performance of the nano-ZnO/BF composite-modified asphalt is significantly improved after adding fibers to the modified asphalt. The average mass loss ratio is only 0.192%. At 46 °C, the rutting coefficient of the composite-modified asphalt was increased by 62.3%. The frequency master curve is always at the highest position and continues to rise, indicating a significant improvement in the high-temperature anti-rutting performance of the composite-modified asphalt. At 24 °C, the creep stiffness modulus S value of the composite-modified asphalt increased by 24.9%; moreover, there is no obvious effect of improving low temperature, but the variation range of creep tangent slope m of the modified asphalt after aging is decreased, which further shows that the addition of a modifier can decrease the influence of aging on asphalt. Nanoparticles are uniformly dispersed in the asphalt and form a three-dimensional interconnected structure with BF, which effectively improves the overall performance of the asphalt. Nano-ZnO and fibers have weak chemical reactions in matrix asphalt, but they are physically dispersed and compatible.

Оцінка якості мармеладу з додаванням багатокомпонентної плодово-ягідної пасти

Today, the manufacturers of the confectionery industry increasingly focus on the production of products with the addition of various types of fruit and berry raw materials, which are characterized by a high content of physiologically valuable nutrients. Traditionally, such raw materials are used in the technologies of marmalade and paste swirls in the form of pastes, purees and stews. Technologies for obtaining such products involve the use of preservatives, the excessive entry of which into the human body is undesirable. Also, during their production, high temperatures are used (boiling, pasteurization, sterilization), which leads to a decrease in the content of some vitamins, causes the destruction of polyphenolic compounds and the loss of the product's original taste and aroma. Considering this, it is relevant to study the possibility of preserving the natural properties of fruit and berry raw materials by using gentle technological modes for its processing, in particular, low-temperature processing. The quality of the developed jelly-fruit marmalade technology with the replacement of 30% of the recipe fruit puree with a multi-component fruit and berry paste was evaluated. The fruit and berry paste is a blended composition of apple-quinceblackcurrant (40:50:10) concentrated in a rotary film apparatus under gentle conditions (temperature 45...50 °С), which contributes to the maximum preservation of the substances of the derived raw materials. The physico-chemical parameters of the studied marmalades are characterized by close values and are at the level regulated by regulatory documentation. Also, the new product has a higher content of pectin substances (1.5 times), vitamin C (4.8 times) and polyphenols (5.4 times) compared to the control sample. According to the value of the integrated quality assessment index, which took into account group indicators (organoleptic, physico-chemical, biological value), the proposed marmalade exceeds the sample made by classical technology by 39%. Thus, the improved marmalade technology is competitive.

Удосконалення технології виробництва функціональних плодово-ягідних напівфабрикатів

The object of this study is a functional fruit-and-berry paste with healthy properties with the selection of components (apples, Ziziphus jujuba, blueberries), which are sources of dietary fiber, vitamin C, low molecular weight polyphenolic compounds and phytosterols, which are used as an immunostimulant to create products with cholesterol-lowering effect. The task to increase the content of these substances is solved by concentrating in a rotary film evaporator (RFE) under mild regime pa¬rameters (60...65 °C) to a dry matter (DM) content of 30...32% for 45...50 s and by the pasteurization of concentrated paste in a scraper heat exchanger (SHE) at a temperature of 95...98 °C followed by packing. The effective viscosity (Pa·s) of the mixtures of the original purees (DM 16...17%) and resulting pastes (30...32%) was determined and its increase 1.65...1.85 times was established in the pastes compared to puree. The obtained data indicate a strengthening of the structure of the resulting functional paste, which, compared to control sample, has 3.6 times more effective viscosity. A significant advantage has a paste containing 45% of apple; 35% of Ziziphus jujuba; 20% of blueberries. It is characterized by 3.8 timesenhanced content of dietary fiber; 2.25 times more content of vitamin C; low-molecular polyphenolic compounds and tannins, phytosterols. Therefore, it can be used as an immunostimulant to manufacture products with cholesterol-lowering effect. It was established that in order to effectively conduct the process of concentration in RFE and subsequent pasteurization in SHE, it is rational to grind puree to a particle size within 0.1...0.5 mm. The heat transfer coefficient when concentrating samples with a particle size of 0.5 mm has a higher rate, by 6%, compared to the sample with a particle size of 1.5 mm. The technology could be introduced at the enterprises of the canning and confectionery industries.

Improving the production technology of functional paste-like fruit-and-berry semi-finished products

The object of this study is a functional fruit-and-berry paste for health purposes with the selection of components (apples, Ziziphus jujuba, blueberries), which are sources of dietary fiber, vitamin C, low molecular weight polyphenolic compounds and phytosterols, which are used as an immunostimulant to create products with cholesterol-lowering effect. The task to increase the content of these substances is solved by concentrating in a rotary film evaporator (RFE) under mild regime parameters (60...65 °C) to a dry matter (DM) content of 30...32 % for 45...50 s and by the pasteurization of concentrated paste in a scraper heat exchanger (SHE) at a temperature of 95...98 °C followed by packing. The effective viscosity (Pa·s) of the mixtures of the original purees (DM 16...17 %) and resulting pastes (30...32 %) has been determined and its increase was found in the pastes compared to puree, by 1.65...1.85 times. The obtained data indicate a strengthening of the structure of the resulting functional paste, which, compared to control, has an effective viscosity of 3.6 times more. A significant advantage has a paste containing 45 % of apple; 35 % of Ziziphus jujuba; 20 % of blueberries. It is characterized by an enhanced content of dietary fiber, by 3.8 times; vitamin C, by 2.25 times; low-molecular polyphenolic compounds and tannins, phytosterols. Therefore, it can be used as an immunostimulant to manufacture products with cholesterol-lowering effect. It was established that in order to effectively conduct the process of concentration in RFE and subsequent pasteurization in SHE, it is rational to grind puree to a particle size within 0.1...0.5 mm. The heat transfer coefficient when concentrating samples with a particle size of 0.5 mm has a higher rate, by 6 %, compared to the sample with a particle size of 1.5 mm. The technology could be introduced at the enterprises of the canning and confectionery industries

Determination of the heat transfer coefficient of a rotary film evaporator with a heating film-forming element

A model of a rotary film evaporator with a film-forming element with a reflective heated surface has been developed. This will allow stabilizing the hydraulic movement of the cut wave flow due to the reflective surface of the geometric shape for the forced direction of the cut raw material to the heating surface. Autonomous heating of the reflective surface additionally provides a temperature effect in the conditions of movement of particles of raw materials after cutting. The analysis of the experimental and theoretical parameters of heat transfer made it possible to substantiate the criterion equation for determining the heat transfer coefficient of an evaporator with the proposed film-forming element and a reflective heated surface for calculating the coefficient from the working surface to the raw material. The resulting equation takes into account the influence of the vertical component of the motion of the raw material film, centrifugal movement during the rotation of the film-forming element, mixing of the boiling film of the raw material with steam bubbles, and the geometric characteristics of the film-forming blade on the hydrodynamic flow of the raw material. The calculation of the rotary-film evaporator was carried out using the criterion equation and the obtained useful heat exchange surface – 0.75 m2. The specific metal consumption in a rotary film evaporator with a film-forming element having a reflective surface is 57 kg/m2, compared to the vacuum evaporator traditionally used in canning industries (410 kg/m2), which is 7.1 times less. The duration of the temperature effect on the raw material is also reduced: a rotary film evaporator – 200 s and 3600 s in a traditional apparatus. The data obtained will be useful for the design of rotary-film devices of different geometric parameters using articulated blades with a reflective plate.

Improved rotary film evaporator for concentrating organic fruit and berry puree

This paper reports the improved rotor-film evaporator with the lower arrangement of the separating space, the auger-type discharge of concentrated organic fruit and berry paste, and preheating the puree with secondary steam. The working surface of the evaporator is heated by a flexible film resistive electric heater of the radiating type with an insulating outer surface. Peltier elements installed in the device make it possible to provide low-voltage power for exhaust fans from the thermal secondary steam. The puree fed for processing is preheated by 8...10 °С by the heat from the concentrated product and secondary steam. For the experiment, fruit and berry blended puree from apples, quince, and black currants was used. The structural and mechanical properties of blended puree have been determined when the temperature changes within 55...75 °С, in particular, the effective viscosity varies in the range of 22...6 Pa∙s, the maximum shear stress ‒ 29...8 Pa. Effective regions in the fruit and berry puree concentration process have been established: Kmin=Vpaste/Vpuree=0.190; Kmax=Vpaste/Vpuree=0.725 When concentrating fruit and berry pastes with an initial solids content of 9...15 % to the resulting content (29...31 %), it is advisable to apply a surface load of 0.048...0.121 kg/m2s. By calculation, the reduction of the specific energy consumption for heating the volume of the product unit has been confirmed: a rotor-film evaporator – 547 kJ/kg over a period of 75 s, compared to the basic vacuum evaporator – 1,090 kJ/kg, respectively, over 1.08 hours. The results could be useful when designing evaporating equipment for rotor-film-type devices in order to concentrate various blends of fruit and berry raw materials under conditions of using the energy of secondary steam.

Improved rotary film evaporator for concentrating organic fruit and berry puree

This paper reports the improved rotor-film evaporator with the lower arrangement of the separating space, the auger-type discharge of concentrated organic fruit and berry paste, and preheating the puree with secondary steam. The working surface of the evaporator is heated by a flexible film resistive electric heater of the radiating type with an insulating outer surface. Peltier elements installed in the device make it possible to provide low-voltage power for exhaust fans from the thermal secondary steam. The puree fed for processing is preheated by 8...10 °С by the heat from the concentrated product and secondary steam. For the experiment, fruit and berry blended puree from apples, quince, and black currants was used. The structural and mechanical properties of blended puree have been determined when the temperature changes within 55...75 °С, in particular, the effective viscosity varies in the range of 22...6 Pa∙s, the maximum shear stress ‒ 29...8 Pa. Effective regions in the fruit and berry puree concentration process have been established: Kmin=Vpaste/Vpuree=0.190; Kmax=Vpaste/Vpuree=0.725 When concentrating fruit and berry pastes with an initial solids content of 9...15 % to the resulting content (29...31 %), it is advisable to apply a surface load of 0.048...0.121 kg/m2s. By calculation, the reduction of the specific energy consumption for heating the volume of the product unit has been confirmed: a rotor-film evaporator – 547 kJ/kg over a period of 75 s, compared to the basic vacuum evaporator – 1,090 kJ/kg, respectively, over 1.08 hours. The results could be useful when designing evaporating equipment for rotor-film-type devices in order to concentrate various blends of fruit and berry raw materials under conditions of using the energy of secondary steam.

Determination of heat transfer coefficient in advanced rotary film evaporator

The object of research is the process of concentrating fruit and vegetable purees in an improved rotary film evaporator. The existing hardware design of traditional processes for processing fruits and vegetables, as a rule, is not unified enough, inconvenient in operation and is designed for high productivity. Concentration of fruit and vegetable purees occurs mainly in vacuum evaporators of periodic and continuous operation at a temperature of 60–80 °C under vacuum, which allows them to significantly preserve their nutritional value. But the duration of the process remains very significant (in devices of periodic action up to 75–90 minutes). One of the most problematic areas in the concentration of fruit and vegetable raw materials is significant losses of biologically active substances. At the same time, an important indicator of the quality of the process of concentrating pasty fruit and vegetable pastes is the value of the heat transfer coefficient, which characterizes the efficiency of the heat transfer method and the design features of the mixing device, taking into account the thermophysical characteristics of the product. To create conditions for conducting research to determine the heat transfer coefficient, it is necessary to use instrumentation with precise regulation of the necessary technological parameters. To study the heat transfer coefficient when concentrating fruit and vegetable purees, an automatic installation of an improved rotary evaporator was designed. The improvement of the rotary film evaporator (RFE) is carried out due to the lower location of the separating space by installing a screw discharge of the paste and preheating the output puree with secondary steam. The experimental dependences of the heat transfer coefficient on the product flow rate make it possible to determine the rational values of the flow rate of the RFE feedstock at various values of the rotor shaft speed. It is found that the heat transfer coefficient is influenced to a large extent by the product consumption, and the rotor speed acts to a lesser extent, only the relative speed of fluid passage around the developed hinged blade changes. It is found that when the frequency changes from 0.3 to 1.7 s–1, an increase in the heat transfer coefficient by 1.45 times is observed, which is explained by a more intensive degree of mixing of the product by the blades.

Improving pastille manufacturing technology using the developed multicomponent fruit and berry paste

A method for manufacturing multicomponent fruit and berry paste based on apples, cranberries, hawthorn with a high content of pectin substances has been improved. A special feature of the technique is the concentration in a rotary film apparatus until a dry matter content of 28... 30 % under a mild mode during 25...50 s provided that the puree is preheated to 50 °C. The limiting shear stress for each type of raw material and the effective viscosity index for the samples of the formulations of the studied pastes have been established. It was found that the best properties are demonstrated by composition with the following formulation ratio of components: apple – 50 %; cranberries – 40 %; hawthorn – 10 %. That makes it possible to obtain pastes with the best chemical composition (the higher content of pectin substances, organic acids, ascorbic acid, etc.). The rational amount of adding 75 % of fruit and berry paste to replace apple puree has been determined and substantiated. That makes it possible to manufacture pastille with a high degree of structure formation, which is confirmed by the viscosity index of 616 Pa∙s, compared with control – 354 Pa∙s. A decrease in the mass fraction of dry substances by 5.0 %, an increase in acidity and reducing substances are ensured, which meets the requirements set by regulatory documents. This amount of paste provides for excellent organoleptic properties, i.e. it gives the products an even red color, pleasant taste, and smell. The developed technology expands the range of "healthy food" by partially replacing raw materials with a low content of physiologically functional components with a multicomponent composition, as well as provides for an increase in the pastille nutritional value. The use of sparing modes of concentration makes it possible to intensify the process of manufacturing a multicomponent paste, which indicates energy and resource-saving technology

Method for producing fruit paste using innovative equipment

A method for the production of multicomponent fruit and vegetable paste has been developed. All components were selected considering the content of physiologically functional ingredients. The method is distinguished using the developed innovative equipment: a multifunctional apparatus for the implementation of preliminary heat treatment of raw materials; rotary film evaporator for concentrating puree. The developed devices are distinguished by increased resource efficiency due to heating with a low-temperature film electric heater with a temperature regime in the range of 45-70 °C. The study of structural and mechanical parameters and organoleptic evaluation of the prototypes allowed to reveal the rational content of raw materials in the developed paste: apples – 30%; viburnum – 20%; black chokeberry – 20%; pumpkins – 20%, beets – 10%.

Dermal and Transdermal Drug Delivery through Vesicles and Particles: Preparation and Applications.

Transdermal delivery over the past decade has become the field of interest for drug delivery due to its various advantages such as no first-pass metabolism, increased drug bioavailability, and easy administration. Different vesicle systems like ethosomes, liposomes, niosomes, and transferosomes along with particle systems like lipid nanoparticles, polymeric nanoparticles, carbon nanotubes, and fullerenes have been developed. These vesicles and particle systems have been developed using various easy and effective methods like cold injection method, rotary film evaporation, thin film hydration, high shear homogenization, solvent extraction method, and many more. These drug delivery systems are a very effective and feasible option for transdermal drug delivery and further developments can be made to increase their use. This article explains in detail the preparation methods and applications for these drug delivery systems.

Catalytic Conversion of a ≥ 200 °C Fraction Separated from Low-Temperature Coal Tar into Light Aromatic Hydrocarbons.

A ≥ 200 °C fraction (CT200F) of low-temperature coal tar was prepared by a rotary film evaporator. The catalytic conversion experiments of CT200F and six model compounds were conducted on the pyrolysis gas chromatography–mass spectrometer. The yields of catalytic conversion products benzene, toluene, xylene, and naphthalene (BTXN) were analyzed by semi-quantitative analysis according to the chromatographic peak areas. Additionally, the possible formation pathways and mechanisms of the target products BTXN generated over different catalysts were investigated. The results show that the yield of aromatic hydrocarbons increases and the yield of acid compounds decreases during CT200F pyrolysis over ZSM-5, HY, USY, and β-zeolite compared with that of its non-catalytic pyrolysis, especially the yields of BTXN obtained over USY and β-zeolite increase by 128 and 108%, respectively. The pore structure of ZSM-5 is suitable to produce BTX, while the suitable acidity and pore structure of USY, HY, and β-zeolite are more beneficial for the selective preparation of naphthalene than that of ZSM-5. The conversion pathways of six model compounds into BTXN over zeolites were obtained, and the following conclusions can be drawn: The dehydroxylation effect of zeolites shows the order of ZSM-5 > HY > USY > β-zeolite. The catalytic effect of zeolites on the cracking and ring opening of PAHs in CT200F shows the order of β-zeolite > USY > HY > ZSM-5. The catalytic effect of catalysts on the cracking and aromatization of aliphatic compounds shows the order of ZSM-5 > β-zeolite > USY > HY. β-zeolite has an outstanding catalytic performance in the conversion of PAHs into naphthalene. ZSM-5 and HY can effectively remove phenolic hydroxyl groups in phenol and naphthol. During the catalytic conversion processes of the coal tar fraction and model compounds, the catalytic effect of the pore constructions of zeolites is more important than their acidities, which determines whether large molecules can enter and whether acid sites in non-micropores can be effectively utilized.

Increasing the efficiency of heat and mass exchange in an improved rotary film evaporator for concentration of fruit-and-berry puree

An improved model of a rotary film evaporator with a cutting blade having a reflective surface and equipped with an autonomous heating system which is fed by a power supply from Peltier elements. The reflective surface of the advanced cutting blade had an area of 0.06 m 2 and was heated by a flexible film resistive electric heater of radiating type with a ~15...20 W power supply. This solution provides additional heating and mixing and helps to capture the cut-off layer of puree while reducing the useful surface of the working chamber by 7 %. Most evaporators have a low heat transfer coefficient reducing the energy content of the process and final quality of the product. The heat exchange efficiency can be increased by improving the design of the film-forming element of the rotary film evaporator. The use of the proposed cutting blade with a reflective surface enables an increase in the heat transfer coefficient by approximately 20 % compared to the basic rectangular blade design. When comparing the calculated data, it can be concluded that the main indicator of resource efficiency, namely specific energy consumption for heating a unit volume of product in the RFE amounts to 408 kJ/kg compared to 1,019 kJ/kg with the basic vacuum evaporator which means a 1.97 times consumption reduction. The duration of heat treatment in the RFE is 60 s compared to 1 h in the basic VE which shows a significant reduction of raw material exposure to high temperatures. The obtained data show the effectiveness of engineering and technological solutions. The engineering and technological component of any heat and mass exchange processes, in particular the concentration of fruit-and-berry raw materials, is the main component in the production of semi-finished food products of a high degree of readiness

Development of a method for producing fruit berry paste and equipment for its implementation

The object of research is the technological process for the production of fruit and berry semi-finished product. Existing technologies for processing fruit and berry raw materials are characterized by the loss of valuable components of the feedstock, namely blanching at a temperature of 85-100 °C and long-term boiling, resulting in loss of vitamins can reach 60%. Hardware design of traditional processes for processing fruits and vegetables, as a rule, is not sufficiently unified, inconvenient in operation and is designed for high productivity. One of the most problematic places is the significant energy and metal waste of traditional equipment and the insufficiently high quality of the finished product. The intensification of the processing of fruit and berry raw materials is possible through the introduction of new technologies and equipment, the use of which can reduce the cost of energy and material resources.During the study, the experimental results of the developed paste were used: apple – 60%; apricot – 30%; cornel – 10%, taking into account organoleptic and physico-chemical indicators. For the technological process of paste production, a hardware line was selected using the developed universal multifunctional device (UMD) and a rotary film device (RFD). This will provide a guaranteed increase in technical and operational indicators with a significant reduction in energy and metal consumption compared to existing analogues. It has been established that for effective puree evaporation in RFD from 11-14% to 27-30% dry matter, it is necessary to grind the raw material to a particle diameter of not more than 0.1-0.5 mm after RFD cooking. The processing temperature of puree in RFD is 62-67 °C, and the concentration time is 2-3 minutes. To reduce the evaporation period and more rational use of RFD, before this operation it is necessary to apply puree to 55-60 °C.The introduction of the developed instrument-technological line will contribute to the production of competitive semi-finished products of high quality with a wide range of uses in food production and restaurant facilities.

Improvement of zefir production by addition of the developed blended fruit and vegetable pasteinto its recipe

A method has been developed for the production of a fruit and vegetable paste-like semi-finished product based on an Antonovka apple, Muscat pearl pumpkin and Bona beet. The method is characterized by concentration in gentle temperature conditions (50...55 °C) in a rotary film apparatus to content of 45 % dry matters lasting 1.25...2.0 min. The structural and mechanical characteristics of the mashed potatoes of the components of raw materials and blended concentrated pastes by the developed method are determined. The structure of the developed fruit and vegetable paste was confirmed to be strengthened, since its maximum dynamic viscosity is 283 Pa∙s, which is 1.9 times more compared to the control (apple paste). Thus, a rational composition is selected for further research with the following components in the paste: apple – 60 %; pumpkin – 20 %, beets – 20 % (composition 1). This paste in comparison with the control has a high content of functional physiological ingredients and has good organoleptic properties. The feasibility of using the developed fruit and vegetable paste in composition of zefirs (composition 1) in the amount of 75 % replacement of apple puree is confirmed. The selected zefir sample differs in its original organoleptic properties. This ensures an increase in the effective viscosity (η ef , Pa∙s) of zefirs with the replacement of 75 % of apple puree with blended paste, compared to control (zefirs without additives) from 391 to 782. The plastic strength (P k ) also increases depending on the duration: 75 % – 54.2 kPa (control sample – 47 kPa), which is generally a positive phenomenon from a technological point of view. Such a solution will provide consumers with food products with physiologically functional ingredients of natural origin, subject to the partial or complete replacement of individual raw materials with blended fruit and vegetable compositions, providing an increase in their functional value

IMPROVEMENT OF ZEFIR PRODUCTION BY ADDITION OF THE DEVELOPED BLENDED FRUIT AND VEGETABLE PASTEINTO ITS RECIPE

A method has been developed for the production of a fruit and vegetable paste-like semi-finished product based on an Antonovka apple, Muscat pearl pumpkin and Bona beet. The method is characterized by concentration in gentle temperature conditions (50...55 °C) in a rotary film apparatus to content of 45 % dry matters lasting 1.25...2.0 min. The structural and mechanical characteristics of the mashed potatoes of the components of raw materials and blended concentrated pastes by the developed method are determined. The structure of the developed fruit and vegetable paste was confirmed to be strengthened, since its maximum dynamic viscosity is 283 Pa∙s, which is 1.9 times more compared to the control (apple paste). Thus, a rational composition is selected for further research with the following components in the paste: apple – 60 %; pumpkin – 20 %, beets – 20 % (composition 1). This paste in comparison with the control has a high content of functional physiological ingredients and has good organoleptic properties. The feasibility of using the developed fruit and vegetable paste in composition of zefirs (composition 1) in the amount of 75 % replacement of apple puree is confirmed. The selected zefir sample differs in its original organoleptic properties. This ensures an increase in the effective viscosity (ηef, Pa∙s) of zefirs with the replacement of 75 % of apple puree with blended paste, compared to control (zefirs without additives) from 391 to 782. The plastic strength (Pk) also increases depending on the duration: 75 % – 54.2 kPa (control sample – 47 kPa), which is generally a positive phenomenon from a technological point of view. Such a solution will provide consumers with food products with physiologically functional ingredients of natural origin, subject to the partial or complete replacement of individual raw materials with blended fruit and vegetable compositions, providing an increase in their functional value.

Synergetic Effect of Nano‐ZnO and Trinidad Lake Asphalt for Antiaging Properties of SBS‐Modified Asphalt

In order to address the influence of aging on the performance degradation of SBS‐modified asphalt, a composite modification of SBS‐modified asphalt by nano‐zinc oxide (nano‐ZnO) and Trinidad Lake asphalt (TLA) was proposed. Several tests were conducted after adding nano‐ZnO and TLA to SBS‐modified asphalt, including a rotary film oven test (RTFOT), ultraviolet aging (UV), and the pressure aging vessel test (PAV). The conventional physical index, rheological index, and four‐component content of SBS‐modified asphalt before and after three aging modes were tested, and the characteristic functional groups in SBS‐modified asphalt were tracked and analyzed by Fourier transform infrared spectroscopy (FTIR). The results show that the effects of aging on the rheological properties of SBS‐modified asphalt are clearly reduced by adding different proportions of nano‐ZnO and TLA in the process of thermal oxygen aging and the ultraviolet aging test, and the antiaging ability of SBS‐modified asphalt is clearly improved. To improve the conventional performance and rheological properties of SBS‐modified asphalt, an incorporation ratio of 3% nano‐ZnO + 25% TLA was proposed. At the same time, the increased rate of heavy components and the change index of the colloidal instability index in the SBS‐modified asphalt under the blending ratio were significantly lower than the blank SBS‐modified asphalt samples in the same aging mode. FTIR spectra also showed that SBS‐modified asphalt performance deterioration were mainly caused by long‐term aging and ultraviolet aging. The addition of nano‐ZnO and TLA effectively reduced the increase of carbonyl groups and the breakage of the C=C double bond in butadiene and synergistically improved the comprehensive aging resistance of SBS‐modified asphalt. Therefore, the use of this modification is an effective method to solve the aging problem of SBS‐modified asphalt.

The Research on Aging Performance of Rubber Asphalt Based on Laboratory Test

Gansu province has complex topography, strong ultraviolet radiation, so the asphalt pavement often appears aging and other diseases in the service period. Firstly, the rubber asphalt for as short-term and long-term were made to be the simulated aging test by the Asphalt rotary film heating test (RTFOT) and the pressure ageing vessel (PAV) accelerated asphalt aging test. Secondly, the rubber asphalt was studied by the UV aging; the RTFOT aged sample was placed to be the ultraviolet aging in ultraviolet radiation box to do the Dynamic shear test (called DSR). The results showed that: the rubber asphalt had better ability to resist fatigue and anti-ultraviolet ageing, suitable for high altitude strong ultraviolet region in Gansu province.

Effect of groove texture on the dynamic characteristics of water-lubricated thrust bearing

In this study, the effects of groove texture on the dynamic characteristics of water-lubricated thrust bearing are theoretically investigated. The turbulent Reynolds equation and its perturbation equations for water-film lubrication are derived and solved by using finite difference method. Dynamic characteristics including the stiffness and damping coefficients of the bearing are calculated. The effects of rotary speed, film clearance and geometrical parameters including groove texture depth and circumferential angle on the dynamic characteristics of the bearing have been investigated.