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[Display omitted] Hypothesis: Limited research has been conducted on the influence of chelating agents on the self-assembly process in surfactant solutions. The traditional approach assumes the chelating agent only interferes as a salting-out ion, therefore promoting surfactant separation. However, the opposite behavior has been observed for iminodipropionate based surfactants, in which the presence of chelating agents of the aminopolycarboxylate type increases solubility of nonionic ethoxylated surfactants in mixed micellar systems. Specific interaction between chelating agents-surfactants can be an important parameter in the self-assembly processes. Experiments: Physicochemical properties of solutions containing amphoteric surfactant and tetrasodium glutamatediacetate have been investigated. Macroscopic properties, such as viscosity and cloud point, were evaluated in the presence of a non-water-soluble alkyl ethoxylated surfactant. Interactions between amphoteric surfactant and chelating agent were monitored by NMR spectroscopy, including 13C chemical shift and lineshape analysis as well as 1H diffusometry. Findings: The study reveals that there is an interaction between the head group of the surfactant and the chelating agent forming oligomeric surfactant analogues with larger hydrophilic moieties, which results in smaller, more spherical micelles. The combined interactions provide possibilities for tuning the aggregation behavior of systems containing surfactants and chelating agents, and with that, the macroscopic properties of the system. [ABSTRACT FROM AUTHOR]

Point cloud registration plays a great role in many application scenarios; however, the registration of large-scale point clouds for actual different moments suffers from the problems of low efficiency, low accuracy, and a lack of stability. In this paper, we propose a registration framework for large-scale point clouds at different moments, which firstly downsamples large-scale point clouds using a random sampling method, then performs a random expansion strategy to make up for the loss of information caused by the random sampling, then completes the first registration by a deep learning network based on the extraction of keypoints and feature descriptors in combination with RANSAC, and finally completes the registration using the point-to-point ICP method. We conducted validation experiments and application experiments on large-scale point clouds of key train components, and the experimental results are much higher in accuracy or efficiency than other methods, which proves the effectiveness of our framework, which can be applied to actual large-scale point clouds. [ABSTRACT FROM AUTHOR]

Cloud point (CP) of aqueous solution of metformin hydrochloride (MNH) and triton X-100 (TX-100) was examined in presence of several alcohols (MeOH, EtOH, 1-PrOH, 2-PrOH, and 1-BuOH). The main focal point of this study was to evaluate the cloud development for the combination of TX-100 and MNH, as well as to indicate the mode of how various alcohols influence both the physicochemical parameters and interaction forces of that mixture. The cloud point (CP) measurement technique was chosen because of its broad applicability in both the medical and industrial sectors. As alcohol contents increased, higher CP values of TX-100 and MNH mixture were observed except in aq. 1-BuOH (CP is decreased). In the aqueous alcoholic medium (above 3000 mmol·kg−1), the phase separation of TX-100 (92.7 mmol·kg−1) and MNH (2 mmol·kg−1) mixture showed the subsequent trend: CP (H2O + 2-PrOH) ˃ CP (H2O + MeOH) > CP (H2O + EtOH) ˃ CP (H2O + 1-PrOH). It was observed that the depth to which alcohol molecules penetrate micelles is influenced by the length of the alcohol chain. Longer hydrophobic alcohol molecules have the ability to impair more ethylene oxide–water (EO-water) interactions by penetrating deeper into the micelle's palisade layer. As a result, there is more occurrence of dehydration, which promotes the production of micellar particles as well as lowers the cloud point substantially. The calculated Δ G c 0 values of the TX-100 + MNH mixture in alcohols media are appeared as positive in every scenario examined, proving that the clouding procedure is not spontaneous. The positive Δ G c 0 results might be attributed to the surfactant's surface layer in forming H-bond via the water molecules. A decrease in the positive Δ G c 0 values is evidenced by a rise in alcohol concentrations. Consequently, there is less non-spontaneity at higher alcohol concentrations. The + Δ H c 0 (endothermic) and + Δ S c 0 magnitudes are detected in aq. MeOH, EtOH, and 2-PrOH solutions. However, Δ H c 0 and Δ S c 0 magnitudes are found as positive (endothermic) and negative (exothermic) at lower and higher contents of 1-PrOH solution while the opposite trend in the Δ H c 0 and Δ S c 0 was detected in aq. 1-BuOH solution. Possible interactions among TX-100 and metformin hydrochloride in aqueous 1-BuOH media [ABSTRACT FROM AUTHOR]

Aqueous solutions of nonionic surfactants behave differently than those of ionic surfactants. Micellar properties and structural characterization of Polysorbate 80 (commonly known as Tween 80) were investigated in the presence of different additives at different temperatures (303–323 K) by using cloud point (CP), densitometry, and viscometry techniques. Nonionic surfactant shows the optimum effect when used near their CP, as the presence of additives strongly influences them. The compounds or additives that break the structure of water will increase the CP, while those that help to build the water structure show a decrease in the CP. Adding ester, urea, and carbohydrates decreases the CP of Polysorbate 80, while alcohol and thiourea show the opposite trend. Density and viscosity measurements of Polysorbate 80 in the presence of monovalent salts (NaX, X = Cl–, Br–, , and salicylate) confirmed the change in molecular structure. [ABSTRACT FROM AUTHOR]

The combination of UAV aerial surveys and LiDAR scanning provides high resolution, accuracy, and data comprehensiveness, which are critical for creating detailed digital models and maps. The aim of the work was to create an orthophotomap and an accurate digital surface model of the research area using a synergy of UAV aerial imagery and airborne LiDAR scanning with laser scanners from two different manufacturers. Aerial surveying with UAVs and aerial LiDAR scanning using two scanners, DJI Zenmuse L2 and CHCNAV Alpha Air 450, was conducted for the territory of the historical and cultural reserve "Ancient Zvenyhorod" in Ukraine, which was chosen as the research object. Based on UAV aerial survey data, an orthophotomap of the study area was created at a scale of 1:2000. Additionally, point clouds of the reserve's surface were generated from the aerial survey data and compared with point clouds obtained from LiDAR scanning. It was determined that, since the object's territory covers 26.8 hectares, the aerial survey was conducted from a height of 145 meters in one flight, while the laser scanning of the territory was carried out at a height of 60 meters to better capture the elements of the area. The scanning operations were automatically divided into two scans with UAV landings for battery replacement. The object's territory located at the junctions of the automatically divided scans lacked point cloud information for both scanners. It was proposed to supplement the LiDAR scanning point cloud with points generated from the aerial survey in the area where they were missing. Before copying the point cloud for the area lacking LiDAR data, an analysis and height alignment of points between the LiDAR data and aerial survey were performed. As a result of the research, an accurate digital surface model of the historical and cultural reserve was constructed, containing all elements of its territory. [ABSTRACT FROM AUTHOR]

The release of the dye Disperse Blue 35 (DB35) into water has serious environmental and health consequences, due to its toxicity and resistance to degradation. This paper investigates the effectiveness of cloud point extraction (CPE) to remove this industrial dye from aqueous solution by Lutensol AO7 and Triton X-114, two environmentally friendly nonionic surfactants. First, the partial phase diagrams of the water–surfactant binary systems are constructed. Then, the effects of pollutants, sodium sulfate and cetyltrimethylammonium bromide on the cloud point temperature (Tc) are determined. The experimental results are expressed by four responses: Extraction efficiency (E), residual concentrations of solute and surfactant in the dilute phase (Xs,w and Xt,w, respectively) and the volume fraction of coacervate (Фc). An empirical smoothing method was applied. For each parameter, the results obtained were modeled using the response surface methodology (RSM) and represented on three-dimensional diagrams. The results show that the efficiency of dye extraction with Lutensol AO7 and Triton X-114 at a concentration of 6 wt% is about 95 % and 82 %, respectively. The influence of salt and ionic surfactant on the effectiveness of CPE for the removal of DB 35 dye was determined. The regeneration of surfactant was only achieved by pH adjustment. [ABSTRACT FROM AUTHOR]

Sedimentation is an undesirable phenomenon that complicates the design of microsystems that exploit dense microparticles as delivery tools, especially in biotechnological applications. It often informs the integration of continuous mixing modules, consequently impacting the system footprint, cost, and complexity. The impact of sedimentation is significantly worse in systems designed with the intent of particle metering or binary encapsulation in droplets. Circumventing this problem involves the unsatisfactory adoption of gel microparticles as an alternative. This paper presents two solutions—a hydrodynamic solution that changes the particle sedimentation trajectory relative to a flow-rate dependent resultant force, and induced hindered settling (i-HS), which exploits Richardson–Zaki (RZ) corrections of Stokes' law. The hydrodynamic solution was validated using a multi-well fluidic multiplexing and particle metering manifold. Computational image analysis of multiplex metering efficiency using this method showed an average reduction in well-to-well variation in particle concentration from 45% (Q = 1 mL/min, n = 32 total wells) to 17% (Q = 10 mL/min, n = 48 total wells). By exploiting a physical property (cloud point) of surfactants in the bead suspension in vials, the i-HS achieved a 58% reduction in the sedimentation rate. This effect results from the surfactant phase change, which increases the turbidity (transient increase in particle concentration), thereby exploiting the RZ theories. Both methods can be used independently or synergistically to eliminate bead settling in microsystems or to minimize particle sedimentation [ABSTRACT FROM AUTHOR]

With multiple merits compared with thermal spray, cold spray technology is widely applied for various application fields. As part of an intelligent cold spray repair system, an approach for three-dimensional (3D) damage region contour extraction is proposed, which is without nominal Computer-Aided Design models and prior knowledge of damaged workpieces. Moreover, due to partially image processing based, the computation load of the proposed method is lower caused by partially avoiding the 3D point cloud processing. According to the results, it is capable to handle the uneven, sparse and unorganized point cloud to precisely extract 3D contour of damage region. The effectiveness of the proposed approach is highlight. Furthermore, the proposed methods on 3D cloud point to grayscale conversion, two-dimensional (2D) edge detection on images, 3D contour reconstruction from 2D edge are also promising for point cloud processing in other application fields. [ABSTRACT FROM AUTHOR]

Point cloud registration plays a great role in many application scenarios; however, the registration of large-scale point clouds for actual different moments suffers from the problems of low efficiency, low accuracy, and a lack of stability. In this paper, we propose a registration framework for large-scale point clouds at different moments, which firstly downsamples large-scale point clouds using a random sampling method, then performs a random expansion strategy to make up for the loss of information caused by the random sampling, then completes the first registration by a deep learning network based on the extraction of keypoints and feature descriptors in combination with RANSAC, and finally completes the registration using the point-to-point ICP method. We conducted validation experiments and application experiments on large-scale point clouds of key train components, and the experimental results are much higher in accuracy or efficiency than other methods, which proves the effectiveness of our framework, which can be applied to actual large-scale point clouds.

Model smart detergents for fruit washing were designed. Their physicochemical and functional properties were determined, with particular emphasis on the efficiency of removing pesticide residues. The specific behavior of nonionic surfactants near the so‐called cloud point was used in the design of the new smart detergent. The high performance of detergents was related to the temperature‐dependent aggregation behavior of surfactants. Liquid chromatography coupled with mass spectrometry (LC–MS/MS) was used to evaluate the washing efficiency. Four types of pesticides (boscalid, acetamiprid, pyraclostrobin and pendimethalin) were applied to apples and then washed with designed detergents. Washing efficiency was evaluated based on the change in pesticide content on the apple surface. Compared to water, the model detergents were found to be more effective in removing pesticide residues, reaching values above 80%. The detergents were also evaluated for skin effects and revealed a low potential for skin irritation. [ABSTRACT FROM AUTHOR]

This work concerns the coacervate extraction of industrial dye, namely Acid Green 9 (AG-9) from aqueous solution by nonionic surfactant Lutensol AO7 and TX-114 (readily biodegradable). Binary water/surfactant and pseudo-binary phase diagrams were plotted. The extraction results as a function of wt% of the surfactant and temperature are expressed by: percentage of solute extracted, E%, residual concentrations of solute and surfactant in the dilute phase (Xs,w and Xt,w respectively) and volume fraction of coacervate at equilibrium (Фc). For each parameter, whose values are determined by a design of experiments, these results are subjected to empirical smoothing in three dimensionsusing response surface methodology (RSM). The aim of this study is to find out the best compromise between E % and Фc. Under optimal conditions, the extraction extent of AG-9 reaches 98 % and 96 % using TX-114 and Lutensol AO7, respectively. The effect of Na2SO4 and CTAB addition is also studied. Finally, the possibility of recycling the surfactant is proved. [ABSTRACT FROM AUTHOR]

This article focuses on the description of novel mixed system formulations of bis-quaternary ammonium salts (bis-QASs) and the nonionic surfactant Triton X-100 (TX-100). Measurements of surface tension (γ), foam stability, contact angle (CA) and cloud point (CP) were investigated at different ratios of the given compounds. The results indicated that changes in the structure of the bis-QASs amphiphilic cation, including the length of the alkyl spacer and the presence or absence of –OH groups, affected the adsorption and micellization. Furthermore, the elongation of the alkyl spacer in the bis-QASs structure affects the increase in the CP temperature. The research carried out shows the future potential of mixed combinations (bis-QASs and TX-100) to be used in industrial applications. [ABSTRACT FROM AUTHOR]

Herein, the phase partitioning of triton X-100 (TX-100) and ceftriaxone sodium trihydrate (CTS) drug mixture in aqueous solutions of sodium salts was thoroughly investigated. The sodium carbonate (Na2CO3), sodium nitrate (NaNO3), sodium oxalate (Na2C2O4), and sodium phosphate (Na3PO4) were used to explore the effect of sodium salts on the cloudy creation of the mixture of TX-100 and applied drug. The CTS is a broad-spectrum cephalosporin antibiotic drug that is extensively utilized to cure bacterial diseases. The CP values of employed system were attained to be lessened by increasing the concentration of sodium salts (Na salts) and followed the pattern: CP aq. NaNO 3 > CP aq. Na 3 PO 4 > CP aq. Na 2 CO 3 > CP aq. Na 2 C 2 O 4 . The estimated several thermodynamic entities ( Δ G c 0 , Δ H c 0 , and Δ S c 0 ) change of phase partitioning of TX-100 + CTS drug is the measurement of interactions that exist between TX-100 and CTS in aquatic Na-salts environments. The calculated ( Δ G c 0 ) values were positive in the studied inspections, which demonstrated the nonspontaneous process of phase partitioning for the investigating system in aq. Na-salts media. The enthalpy–entropy compensation variables associated with the clouding process of TX-100 + CTS mixture in H2O + salts media were also calculated and interpreted in a detailed way. The operating forces between TX-100 and CTS are electrostatic and hydrophobic, which is evident from the values of Δ H c 0 and Δ S c 0 . [ABSTRACT FROM AUTHOR]

Cooking oil undergoes rigorous purification stages before reaching the market, which likely contributes to the elevated purity achieved through solvent-aided crystallization (SAC). However, the utilization of cooking oil as biodiesel feedstock is not suitable as it is expensive, resource inefficiency and lack of sustainability. Therefore, utilization of unpurified crude palm oil (CPO) for biodiesel production is an effective replacement. This study aims to assess the efficacy of SAC using unpurified CPO as the biodiesel feedstock. Parameters investigated include crystallization temperature (6 °C–14 °C), crystallization time (20–40 min), and shaking speed (32 rpm–84 rpm). Analysis reveals that CPO exhibits a high pour point of 15.7 °C and a cloud point of 10.8 °C, indicating potential operational and storage challenges. However, crude biodiesel derived from CPO demonstrates improved characteristics, including reduced pour point, cloud point, viscosity, and density, similar to the improvements seen in purified biodiesel obtained after SAC. The findings indicate that the most suitable operating conditions to maintain low pour and cloud points are a crystallization temperature of 10 °C, crystallization time of 30 min, and shaking speed of 61 rpm. Despite these improvements, both crude and purified biodiesel surpass ASTM D6751 limits for pour and cloud points, underscoring the necessity for further optimization in biodiesel production to meet industry standards. This research highlights the potential of SAC in enhancing biodiesel quality from unrefined feedstocks, offering a cost-effective and scalable method for producing higher-quality biodiesel while addressing current limitations.

Sedimentation is an undesirable phenomenon that complicates the design of microsystems that exploit dense microparticles as delivery tools, especially in biotechnological applications. It often informs the integration of continuous mixing modules, consequently impacting the system footprint, cost, and complexity. The impact of sedimentation is significantly worse in systems designed with the intent of particle metering or binary encapsulation in droplets. Circumventing this problem involves the unsatisfactory adoption of gel microparticles as an alternative. This paper presents two solutions—a hydrodynamic solution that changes the particle sedimentation trajectory relative to a flow-rate dependent resultant force, and induced hindered settling (i-HS), which exploits Richardson–Zaki (RZ) corrections of Stokes’ law. The hydrodynamic solution was validated using a multi-well fluidic multiplexing and particle metering manifold. Computational image analysis of multiplex metering efficiency using this method showed an average reduction in well-to-well variation in particle concentration from 45% (Q = 1 mL/min, n = 32 total wells) to 17% (Q = 10 mL/min, n = 48 total wells). By exploiting a physical property (cloud point) of surfactants in the bead suspension in vials, the i-HS achieved a 58% reduction in the sedimentation rate. This effect results from the surfactant phase change, which increases the turbidity (transient increase in particle concentration), thereby exploiting the RZ theories. Both methods can be used independently or synergistically to eliminate bead settling in microsystems or to minimize particle sedimentation

Objective In order to remove paraffin from white oil and reduce its cloud point, filter aids were applied to methyl ethyl ketone (MEK)-toluene dewaxing process of the white oil. Methods The influences of the volume percentage of MEK in the mixed solvent, the volume ratio of solvent to white oil, and the dewaxing temperature on the dewaxing effect were studied. Three types of comb-type copolymers denoted AMAC, EMAC and Azo-MAC were obtained by the reaction of maleic anhydride-α-octadecene copolymers with aniline, phenylethylamine and amino-azobenzene, respectively. The effects of polymer types and addition amount on the MEK-toluene dewaxing were studied. Results The optimum dewaxing effect was obtained at a MEK ratio of 55%, a solvent ratio of 3.0∶1, and a dewaxing temperature of-14 ℃ without filter aids, the wax yield was 5.6% and the cloud point was-2 ℃. Under the optimal process conditions, the wax yield was improved to 5.9% and 6.0% and the cloud point reduced to-4 ℃ by adding 100 μg/g of AMAC and EMAC with a molar ratio of side chain to main chain of 2∶1, respectively. Conclusions Polymer AMAC and EMAC show the characteristics of filter aids. Adding the filter aids AMAC and EMAC in the MEK-toluene dewaxing process of white oil can improve the dewaxing effect and increase the wax precipitation point. [ABSTRACT FROM AUTHOR]

The study of phase separation of triton X-100 (TX-100) and levofloxacin hemihydrate (LFH) mixture in aqueous solutions of electrolytes has the keen interest due to the enormous applications in pharmaceutical sectors. Levofloxacin hemihydrate is a third-generation antibiotic drug utilized in the prevention of bacterial diseases. Herein, phase separation or cloud point (CP) temperature of TX-100 + LFH in aqueous solutions of simple sodium salts (sodium acetate (NaOAc), sodium sulfate (Na2SO4), sodium carbonate (Na2CO3), sodium chloride (NaCl), and sodium citrate (Na3CTA)) with varying concentration was explored at atmospheric pressure. Herein, CP temperature was recorded by visual assessment. The achieved cloud point (CP) values of TX-100 + LFH system in the attendance of electrolytes were observed to be decreased with the enhancement of electrolytes. Among employed electrolytes, SO42− was the most effective depressor of CP values due to its salting-out effect. The reducing trend in the CP values of TX-100 + LFH with subsequent enhancement of concentration of electrolytes follows the order: CP Na 3 CTA > CP Na 2 SO 4 > CP Na 2 CO 3 > CP NaCl > CP NaOAc . The calculated Gibbs free energy ( Δ G c o ) values for the phase separation of TX-100 + LFH system were found to be positive which directed the phase separation process is nonspontaneous. The enthalpy changes ( Δ H c o ) and entropy changes ( Δ S c o ) of clouding were found to be negative at all concentrations of electrolytes and only positive value achieved at high concentration (900.1 mmol kg-1) of Na3CTA. The assessment of entropy-enthalpy compensation was performed and explained with proper clarification. [ABSTRACT FROM AUTHOR]

Drilling into the permeable reservoir experiences the migration of drilling mud filtrate into the reservoir formation, which eventually results in the formation of flushed and transition zones within the reservoir. This interaction of drilling mud and the formation fluid in these zones usually has some profound effect on the cold flow and reservoir fluid properties when flowed to surface. An experimental work was conducted to evaluate the effect of drilling mud additive interaction with the reservoir fluid at surface conditions to find out any flow assurance-related concern during the flow back and or well commissioning. The project was started by obtaining the sample from an oil and gas field located in the Northern area of Pakistan. Initially the crude oil was classified as a lighter product with API° gravity of 49.52° and density of 782 kg/m3. The cold flow properties that include cloud point and pour point were 6 °C and – 1 °C, respectively, for the studied crude oil. During this study, the crude oil was physically interacted with four different polymeric water-based drilling mud, which belongs to three different classifications of polymers; biopolymers, synthetic, and modified polymers. Upon the interaction with different polymeric mud systems, the API° gravity changes and the maximum API° gravity obtained was 55.18° in sodium alginate system, while minimum of 45.74° was attained in PAC-L system. Moreover, similar variations were also observed in the crude oil density. The initial crude density of 782 kg/m3 increased to 798 kg/m3 in PAC-L, while substantially dropped to 758 kg/m3 in sodium alginate. In addition, the variations in the cold flow properties that include pour point and cloud point were observed after interaction between crude oil and the mud samples. No considerable change was witnessed in cloud point in any of the samples. A maximum change of 0.3 °C was perceived in cloud point after day 1 in sample contaminated with PAC-L. On the other hand, this change increased to 0.5 °C on day 10 in PAC-L and PHPA samples. All the remaining samples demonstrated cloud points closer to 6 °C, which was similar to the uncontaminated crude oil sample. Conversely, significant variation was noticed in the pour point of all the samples. Sodium alginate and pure-bore contaminated samples showed a decrease in pour point by – 5 °C and − 4.5 °C, respectively. Modified and synthetic polymeric contaminated samples show pour points closer to the initial uncontaminated crude oil sample. All these results give a conclusion that biopolymers can be used in drilling mud and it does not have any significant change on the cold flow and reservoir fluid properties which is of paramount importance while flowing back the well to commission it during the winter season when the ambient temperature drops below 0 °C. [ABSTRACT FROM AUTHOR]

A watercolor is an art form that uses water to express the painting process. Water is the specific boundary that distinguishes watercolor from other painting types. Fluidity is one of the essential factors constituting its distinctive artistic beauty. With vibrant hues and delicate brushstrokes, 3D watercolors enhance the image's content with more meaningful information. It has more visual impact than a watercolor that is flat. Appreciators can visualize the scenario in their minds, which leaves more room for imagination and is particularly useful for usage in animation. This paper uses 3D point cloud reconstruction to enhance the 3D effect of watercolor and proposes a 3D reconstruction method of the point cloud based on a generative adversarial network. First, a new mesh model is obtained by using a predictor to predict the offset of the mesh model edge. Then, the point cloud classifier in the discriminator is used to extract the high dimensional features of the original point cloud data and the surface sampling point set of the mesh model. Finally, the output data of the predictor and discriminator are associated with the adversarial training method, and the network model is optimized through several iterations to obtain a 3D mesh model satisfying the spatial characteristics of the point cloud. The experimental results demonstrate that the method suggested in this paper is superior to the three benchmarks in terms of watercolor's texture, color transition, highlight part, and iteration time, as well as its ability to enhance the 3D effect. [ABSTRACT FROM AUTHOR]

Pluronic block copolymers have phase behavioural characteristics which are extensively studied for drug delivery applications. In this study, we explored hydrophilic pluronic F108 (HLB = 27), hydrophobic pluronic L81 (HLB = 2) and their mixed micelles acting as solubilising mediums for model drug aceclofenac. The drug solubilisation and interactions have been analysed using UV-visible spectroscopy, Fluorescence spectroscopy, Rheology studies, Fourier-transform infrared spectroscopy, Scanning electron microscope, Dynamic light scattering, Cloud point and partition coefficient measurements. The investigation from UV-spectrophotometry demonstrated that mixed pluronic entrapped greater number of aceclofenac molecules than both the neat pluronics at same concentration. Excimer formation was evidenced from fluorescence spectra with pyrene as a probe. The rheological studies showed difference in viscosity over low shear range. Studies on FTIR demonstrated probable bonding between the aceclofenac and mixed pluronic molecules. The DLS studies on mixed pluronic showed swelling of micellar diameter from 317.6 nm to 413.5 nm. Thermodynamic parameters of the above system revealed higher partition coefficient value for mixed pluronic and spontaneity in drug solubilisation. This study can be exploited to use a hydrophobic copolymeric micelle in mixed pluronic formulation for better drug solubilisation.

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Extraction of flavonoid glycosides and flavonoid aglycones simultaneously by enzyme-assisted micelle-mediated extraction has been proposed in this study. The discarded apple tree branches pruned during winter dormancy were selected as model materials. Extraction of phloretin (flavonoid aglycone) and phlorizin (flavonoid glycoside) from the discarded apple branches by micellar aqueous solution of nonionic surfactants with assistance of enzyme was performed to validate the method. Influencing factors like temperature, pH, time, enzyme concentration, surfactant concentration, solid to liquid ratio, and the ratio of pectinase to cellulase on the extraction yields of phloretin and phlorizin were discussed by single-factor experiments, and the main influencing factors were optimized by response surface methodology using Design-Expert 8.0.6 statistical software according to the Box-Behnken experimental design principle. The interaction of surfactants and enzymes in the extraction process was also investigated. Results indicate that the surfactants increased solubility of flavonoid glycosides and flavonoid aglycones in water simultaneously; enzymatic hydrolysis increased the diffusion rate of target components to the extraction medium and transformed flavonoid glycosides into flavonoid aglycones at the same time. Therefore, flavonoid glycosides and flavonoid aglycones were extracted simultaneously by micellar aqueous solution. The cloud point effect of nonionic surfactants separated the extracting solution into two distinct phases, which results in the concentration of the target component. In addition, the surfactant has low toxicity and volatility, making the extraction process more safe and reliable. Therefore, the process developed in this study provides an efficient and environmentally friendly technique for flavonoid glycoside and aglycone extraction simultaneously. [ABSTRACT FROM AUTHOR]

As a result of the special advantages of infrared such as ambient does not affect by IR heating, being environmentally friendly, reducing the size of equipment used in food heating and ease of control. Moreover, it is one of the most promising techniques, so the current study aimed to investigate the application of infrared ray in extracting the oil of common carp fish wastes (Cyprinus carpio L.), and the study of the effect of the independent factors, which are: power (130, 190, 250 watts), temperature (50, 60, 70 ºC), the distance between the radiation source and the surface of the waste (1, 15.5, 30 cm) on the freezing point, cloud point and pour of carp waste oil using response surfaces methodology. The results showed that the lowest practical and predicted values for the above traits were -4.6, -3.1, 11.9, 12.2, 6.8, and 7.01, respectively, and that the increase in power and temperature had a negative effect, as it led to an increase in the cloud point. The results illustrated that the interaction between distance, power and temperature led to a decrease in the freezing point. The results also clarified that the increase in power with a decrease in temperature and stability of the distance led to an increase in the pour point. The results indicated that the optimal conditions were the power 315.94W, the temperature 66.14° C, and the distance is 20.02 cm. The results of the statistical showed that the nonlinear multiple regression equation was used to predict the values of the cloud point, while the multiple linear regression equation was used to predict the pour point values. The nonlinear multiple regression equation had a non-significant effect to predict the freezing point values, with an error rate ranging from 0.32% to 30%.

Diesel fuel has several advantages over other petroleum fuels, however, its performance largely depends on the cold flow properties like cloud point (CP), pour point (PP) and cold filter plugging point (CFPP) and their poor values may result in fuel solidification leading to blockages of fuel in lines and filters. The cold flow properties as well as physical properties are highly dependent on composition of diesel fuel. Herein, blending of several diesel fuel samples of atmospheric distillation unit, hydrocracker and hydro-process unit were investigated in different ratio. The results of blending indicated that blend DH-9 exhibited significant improvement in the cold flow properties, displaying CP, PP, CFPP at −17 ± 0.48 °C, −22 ± 0.62 °C, and −27 ± 0.03 °C, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] Switchable assemblies relevant for bio-applications may be accessed from water-soluble tetra- ortho -substituted azobenzenes that reversibly self-assemble and form complexes with β-cyclodextrin under visible light. Two azobenzenes bearing either four fluorines or two chlorines and two fluorines in the ortho positions were synthesised with short poly(ethylene oxide) tails for water solubility. Photophysical properties were determined by UV–vis and 1H NMR spectroscopies, complexation with β-cyclodextrin was assessed by 1H NMR spectroscopy, and self-assembly in water was investigated by static and dynamic light scattering. Both molecules underwent trans – cis isomerization at 530 nm and cis – trans isomerization at 415 nm, with the cis forms exhibiting thermal half-lives > 300 days at room temperature. Both molecules formed inclusion complexes with β-cyclodextrin in water, with cis -4F-AZO-PEO binding 3-fold stronger than trans , and 2Cl2F-AZO-PEO binding significantly weaker. Self-assembly of pure 2Cl2F-AZO-PEO in water showed an open association process regardless of configuration, while 4F-AZO-PEO showed an open association process for cis (N agg increasing from 30 to 1000) but a closed association process for trans (N agg stable at ∼ 170). Aqueous solutions of 2Cl2F-AZO-PEO showed cloud points close to 45 °C, while the 4F-AZO-PEO isomers presented well-separated cloud points allowing reversible and all-visible transition between clear and turbid states at room temperature. [ABSTRACT FROM AUTHOR]

An amphiphilic aryl-ether AB2-type dendron (l) bearing oligo ethylene glycol (OEG) chains exhibited lower critical solution temperature behavior in aqueous solutions. In the presence of the salting-out salts (Na2SO4, NaCl, and NaBr), the cloud points of 1 decreased linearly with increasing salt concentration. The slope of the linear decrease changed with the anion type in the order, SO42- > Cl- > Br-. In the presence of the salting-in salts (NaSCN and NaI), the cloud points of 1 increased non linearly with increasing salt concentration. The shape of these curves can be well fitted by adding a Langmuir binding isotherm to the linear term used for the salting-out salts. When monohydric alcohols (ethanol and 1-propanol) were added to the aqueous solutions of 1, the cloud points barely changed but were reduced after adding polyhydric alcohols (ethylene glycol, xylitol, and D-sorbitol). The salt effect on the cloud points of 1 was negligible in the aqueous polyhydric alcohol solutions. Conversely, the addition of monohydric alcohols to the aqueous solutions could amplify the salt effect on the cloud points. The alkyl groups of monohydric alcohols could be hydrated by water molecules accompanied by the formation of a hydration shell with a clathrate-like structure. Hence, free water molecules are consumed by adding monohydric alcohols to the aqueous solutions. Overall, the amplification of the salt effect on the clouding points of 1 could be deduced by increasing the salt concentration around 1. [ABSTRACT FROM AUTHOR]

Spherical polyamide 12 (PA12) powder for selective laser sintering (SLS) was prepared by thermally induced phase separation (TIPS) method. It was authenticated that the mixed solvent can regulate the liquid–liquid phase separation (LLPS) process by changing the ratio of diluent to non-diluent. The polymer droplets mainly coalesced in the solution, and then the crystal nucleus of PA12 was formed in the droplets. Finally, high crystallinity PA12 powder was precipitated. The morphology, particle size distribution, thermal properties, the change of crystal structure, and powder spreading performances of the obtained powder were characterized. The powder had a narrow particle size distribution, an average particle size of 55.2 μm, and a broad sintering window of 29°C. The results exhibited that the powders prepared by TIPS had excellent sintering properties, and TIPS method provided more choices for SLS technology.

Bovine serum albumin (BSA) is widely used in tissue engineering and pharmaceutical research. It is readily available as a byproduct of the cattle industry, and collected from blood. In this study, we conducted a physicochemical investigation of the phase separation in a mixture of Triton X-100 (TX-100) and BSA, influenced by various polyols, using the well-established cloud point (CP) determination method. The addition of polyols resulted in a significant reduction in CP values for the TX-100 + BSA mixture. The magnitudes of CP in the experimental system were highly varied with different polyols and followed the order of: CP H 2 O + Xylose > CP H 2 O + Mannose > CP H 2 O + Arabinose > CP H 2 O + Fructose > CP H 2 O + Dextrsoe > CP H 2 O + Glucose > CP H 2 O + Maltose. Under identical conditions, the system exhibited maximum solubility in the xylose solution and minimum solubility in the maltose solution. The positive ΔG c 0 values were acquired in all working medium imply the nonspontaneity of phase transition in the TX-100 + BSA system. At lower polyol contents, the negative values of standard enthalpy (∆ H c 0) and standard entropy (∆ S c 0) changes were observed, suggesting that electrostatic forces dominated as the driving force for clouding. At highest employed polyols concentration in some case, the positive values for ∆ H c 0 and ∆ S c 0 were achieved, which indicated that hydrophobic interactions likely dominate the phase partitioning of the amphiphile and protein mixture. Additionally, entropy-enthalpy compensation parameters were calculated and analyzed with a rational approach. Molecular docking analysis further demonstrated the presence of hydrogen bonds and hydrophobic interactions between TX-100 and BSA. [ABSTRACT FROM AUTHOR]

[Display omitted] • The interaction between Solutol®HS15 and urea is crucial for designing ophthalmic formulations. • The study focuses on clouding behavior and micellar characteristics of Solutol®HS15 in the presence of denaturants. • CP increases in the order of dimethylurea > methylurea > urea suggesting increased hydrophilicity. • DLS and SANS indicate micellar breakdown in the presence of urea and its derivatives. In the field of ophthalmology, significant attention is dedicated to developing micellar carriers to enhance ocular drug delivery. Urea is a well-known denaturant and has been used as an excipient in several ocular formulations due to its efficacy as an ocular hypotensive agent. The presence of urea as an excipient may influence the characteristics of the micellar nanocarrier in the formulation and needs to be investigated. Solutol® HS15, a well-known nonionic surfactant and a commonly used nanocarrier in drug formulations, enhances the solubilization and stability of ocular drugs. However, a detailed study of its interaction with various pharmaceutical excipients is still lacking. With this intention, the present study focuses on comprehending the interaction between Solutol® HS15 micelles with urea and its derivatives. Here, we present a detailed analysis on the influence of urea and its derivatives (methylurea, dimethylurea) on Solutol® HS15 using small-angle neutron scattering (SANS), dynamic light scattering (DLS), and cloud point (CP) measurements. The presence of urea and its derivatives strongly affects the CP, leading to a significant increase in its values when urea derivatives are present. Additionally, the SANS and DLS results also indicate a significant decrease in micellar size, suggesting demicellization. The observed effects of urea derivatives on Solutol® HS15 micelles underscore the importance of considering solvent-surfactant interactions in understanding the behavior of surfactant-based systems. This research will provide greater insight into the interactions between urea and its derivatives and Solutol® HS15, which will assist in understanding the morphology and size distribution of surfactant micelles for drug delivery applications. [ABSTRACT FROM AUTHOR]

In this study, the physicochemical properties of linseed and linseed biofuel were studied and their effect on the flow properties of Nigerian waxy crude oil at different volume fractions was investigated. The Nigerian wax crude oil was characterized for its specific gravity, API gravity, wax content, pour point and cloud point. The properties of the linseed oil and linseed biodiesel investigated include: density, specific gravity, viscosity, pour point, cloud point and flash point. Upon esterification of the free fatty acid (FFA) contained in the linseed oil reduced from 3.5 to 0.75 and the viscosity of the seed oil reduces from 2169 to 362 mm2/s. The linseed oil and its biodiesel exhibited similar trend of reduced viscosity at higher shear rate, however, linseed biodiesel demonstrated the lowest viscosities, cloud points and pour points owing to reduced fatty contents. The effect of the linseed oil and its biodiesel on the pour point and cloud point of the waxy crude oil was determined; and the performance compared to that of xylene. A rapid drop in the pour point and cloud point was observed with the wax crude pre-heated with 0.1 v/v linseed oil, its biodiesel and xylene.

Pluronic block copolymers have phase behavioural characteristics which are extensively studied for drug delivery applications. In this study, we explored hydrophilic pluronic F108 (HLB = 27), hydrophobic pluronic L81 (HLB = 2) and their mixed micelles acting as solubilising mediums for model drug aceclofenac. The drug solubilisation and interactions have been analysed using UV-visible spectroscopy, Fluorescence spectroscopy, Rheology studies, Fourier-transform infrared spectroscopy, Scanning electron microscope, Dynamic light scattering, Cloud point and partition coefficient measurements. The investigation from UV-spectrophotometry demonstrated that mixed pluronic entrapped greater number of aceclofenac molecules than both the neat pluronics at same concentration. Excimer formation was evidenced from fluorescence spectra with pyrene as a probe. The rheological studies showed difference in viscosity over low shear range. Studies on FTIR demonstrated probable bonding between the aceclofenac and mixed pluronic molecules. The DLS studies on mixed pluronic showed swelling of micellar diameter from 317.6 nm to 413.5 nm. Thermodynamic parameters of the above system revealed higher partition coefficient value for mixed pluronic and spontaneity in drug solubilisation. This study can be exploited to use a hydrophobic copolymeric micelle in mixed pluronic formulation for better drug solubilisation. [ABSTRACT FROM AUTHOR]

The paper reviews the possibility of obtaining all-season diesel fuel that can be effectively used in both Arctic and subtropical climates. The resulting fuel has a cetane number at the required level for summer diesel fuels of Euro 5 standard, a flash point of at least 62°C, and a pour point of less than –55°C without the use of a depressant-dispersant. The conducted research showed that none of the narrow fractions isolated from oil typical of refineries in the central part of the Russian Federation had the required properties, even taking into account the addition of ignition promoters. The improvement of the low-temperature properties due to cracking of n-alkanes during catalytic dewaxing leads to a significant decrease in the cetane number. Therefore, this paper considers the application of a diesel-fuel isodewaxing process on a platinum catalyst. This process makes it possible to improve significantly the low-temperature properties of the dewaxed product with a moderate decrease in its cetane number. The optimal conditions for the isodewaxing process were determined. The optimal feed for the unit was selected. [ABSTRACT FROM AUTHOR]

Condensation polymerization, catalytic breakdown, kink production, and double bond induction in the feedstock have been tested first time for biodiesel production. Biodiesel as an alternative fuel has gained much importance in the past few decades. Still, higher densities and poor low-temperature flow properties have made its excessive usage quite questionable. Therefore, the present research work was designed to overcome the above-mentioned problems by taking a step towards sustainable development of renewable energy sources. The fatty oil of Pongamia pinnata was extracted, vacuum filtered, fractionated, and treated to optimize the carbon chain length of fatty acids (by condensation polymerization, catalytic breakdown, kink production, and double bond induction) prior to the base-catalyzed transesterification. The highest biodiesel yield (%) was obtained by removing excessive long-chain fatty acids that could cause the hindrance in transesterification reaction and reduce the quality of fuel. The gas chromatographic analysis of fatty acids of Pongamia pinatta showed the highest percentages of oleic acid (54.76 ± 0.001%), linoleic acid (11.87 ± 0.085%), and palmitic acid (10.03 ± 0.014%). The results of the present study showed the best low-temperature flow properties of fraction-ethylene glycol-L-V [(cloud point (CP): 1.7 ± 0.056 °C) and (pour point (PP): −5.2 ± 0.098 °C)] and fraction-catalytic breakdown-L-II [(cloud point (CP): 1.5 ± 0.054 °C) and (pour point (PP): −5.2 ± 0.023 °C)]. [ABSTRACT FROM AUTHOR]

In this study, the effect of the hydrophilic–lipophilic balance (HLB) number and cloud point (CP) of a secondary-alcohol ethoxylated nonionic surfactant on degreasing efficiency was investigated. A degreasing process was conducted for steel samples with different surfactants in a degreasing solution. The HLB number and CP increased with the increasing n of the hydrophilic ethylene oxide (OCH2CH2)n group. For a constant temperature of the degreasing solution (30–80 °C), the degreasing efficiency was investigated as a function of degreasing time. The highest degreasing efficiency was observed near the cloud point of the surfactant, and the degreasing efficiency decreased significantly at temperatures lower and greater than the cloud point. A Hogaboom test was carried out to observe oil stains on the surface of samples. Additionally, the contact angle of the surface with water droplets was measured after degreasing with various surfactants. [ABSTRACT FROM AUTHOR]

This study describes preparation a new series of tetra-dentate N2O2 dinuclear complexes Cr(III), Co(II)and Cu(II) of the Schiff base 2-[5-(2-hydroxy-phenyl)-1,3,4-thiadiazol-2-ylimino]-methyl-naphthalen-1-ol], (LH2) derived from 1-hydroxy-naphthalene-2-carbaldehyde with 2-amino-5-(2-hydroxy-phenyl)-1,3,4-thiadiazole. These ligands were characterized by FT-IR, UV-Vis, Mass spectra, elemental analysis, and 1H-NMR. All prepared complexes have been characterized by conductance measurement, magnetic susceptibility, electronic spectra, infrared spectrum, thermal Analysis (TGA), and metal analysis by atomic absorption. The stoichiometry of metal to ligand, magnetic susceptibility, and electronic spectra measurements show an octahedral geometry for all (Cr3+, Co2+, Cu2+) complexes. Conductivity measurement shows that the prepared (Co2+, Cu2+) complexes were nonelectrolyte except (Cr3+). Studying the extraction efficiency such as ligand concentration, temperature and incubation time, centrifuge time, amount of surfactant were evaluated and optimized. The linear range of ions Cr(III), Co(II) and Cu(II) with ligand (0.2–3, 0.2–4, 0.2–3, µg mL–1), each individually, and relative standard deviation (0.15%, 0.34%, 0.46%). The successful method was applied for the determination of trace metal ions in the wastewater.

The micellar shape of octyl ether octaethylene oxide carboxylic acid ([H+][C 8 E 8 c−]) is restricted to spheres. A classical core–shell micellar regime (L 1) at lower surfactant concentrations transitions into a regime of head-group interdigitated micelles (L 1 ′) at higher concentrations. In the surfactant's sodium or calcium salts the micelles are deformed from spherical to slightly prolate spheroidal. The formation of a hexagonal (H 1) phase within the transition regime between L 1 and L 1 ′ is possible by a reduction of the area per molecule by counterion bridging. An increase in temperature decreases the influence of ion bridging and 'melts' the H 1 phase into a nematic phase (N) consisting of shorter chains of prolate micelles with a preferential orientation (grey arrow). [Display omitted] In a recent paper, we determined the phase behavior of an aqueous solution of octyl ether octaethylene oxide carboxylic acid ([H+][C8E8c−], Akypo™ LF2) and with partial replacement of H+ by Na+ and Ca2+. It was found that even the neat surfactants are liquid at room temperature and that they form only direct micelles for any aqueous content and over large temperature ranges. The aim of the present work was to find an explanation for the clouding in these systems as well as for the coacervation observed at very low surfactant content. We expected that very similar phase diagrams would be found for a full replacement of H+ by the mentioned ions. We established the respective phase diagrams of the above-mentioned salts in water and determined the structures of the occurring phases in detail with small-and wide-angle X-ray scattering, small-angle neutron scattering, dynamic light scattering, heat flux differential scanning calorimetry, as well as surface tension, ESI-MS, and NMR experiments. To our surprise, we discovered a new type of nematic phase between an isotropic and a hexagonal phase. Based on the complete description of all occurring phases both in the acidic and the charged surfactant systems, we were able to design a coherent and unified picture of all these phases, including the auto-coacervation at low surfactant concentration, the non-conventional clouding at high temperatures, the unusual liquid crystalline phases in a small domain at high surfactant concentrations, and the L β phase at low temperatures and at very low water content. It turned out that all phenomena are a consequence of the subtle interplay between a) the packing constraint due to the very large head-group, b) the relatively small hydrocarbon chain and c) the tunable electrostatic interactions versus entropy. [ABSTRACT FROM AUTHOR]

Algal biomass is good source of oils and it can be used for producing biodiesel. The present work is a study of biodiesel production from the algal blooms. Microcystis species was isolated from the blooms and cultured in BG-11 medium. The biodiesel was extracted using alkali catalyzed transesterification method. The trans esterified oil was collected and subjected to GC MS analysis. The FAME profiles showed the presence of unsaturated fatty acids which confirms the presence of biodiesel. The extracted biodiesel was also characterized for the physical properties like fatty acid value, saponification value, iodine value, cetane number, kinematic viscosity, pour point and cloud point. [ABSTRACT FROM AUTHOR]

[Display omitted] • Achieving significant functionalization in copolymers based on NIPAM and DMA is possible through catechol groups. • 1H NMR analysis provides crucial information on the functionalization degree. • Incorporation of organometallic complexes results in an increase in the cloud points of functionalized copolymers. • Increasing DMA content results in remarkable hysteresis, in clear association with the microstructure: NIPAM and NIPAM + DMA sequences linked to Cp 2 Ti. Smart polymers remain a compelling focus for researchers and industries due to their remarkable efficiency, adaptability, and specificity. These dynamic systems can react to external stimuli by altering their physicochemical properties, holding immense potential for a new wave of intelligent applications. The strategic functionalization of stimuli-responsive polymers unlocks ways for novel smart properties. An illustrative example is the integration of organometallic complexes, offering exciting prospects for augmenting heterogeneous catalysis and achieving precise control over drug release. It's crucial to acknowledge that the current state of functionalization while promising, is constrained by intricate and multifaceted procedures. In this pursuit, we propose a novel approach: functionalizing catechol groups within polymeric chains of N-isopropylacrylamide using high concentrations of bis(cyclopentadienyl)titanium(IV) dichloride, achieving unprecedented levels of organometallic attachment (4.05 mol %). Our findings, validated through 1H NMR analysis, confirm the successful integration of organometallic complexes while shedding light on the underlying reaction mechanisms. Moreover, these materials exhibit intriguing changes in their cloud points, which are directly influenced by the presence of organometallic compounds, resulting in differences of over 10 °C for samples with the highest contents. This research underscores the potential of tailored polymer functionalization strategies in advancing smart materials for diverse technological applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Drug-surfactant interactions using cloud point (CP), UV–visible and molecular dynamics simulation. • SDS caused CP enhancement of TTX-100 + metformin hydrochloride (MMH) system. • CMC for TTX-100 + MMH mixture were determined using UV–visible method. • Δ H c 0 , Δ S c 0 , thermodynamic transfer parameters and compensation factors were computed. • Using molecular dynamics simulation, atomic-scale interactions between MMH and TTX-100 were unveiled. The mode of interaction of surfactant with drug remains a keen interest in the research area owing to the improvement of drug carrier systems in therapeutic formulations. In order to investigate the drug-surfactant interactions between triton X-100 (TTX-100) and an antidiabetic drug metformin hydrochloride (MMH); the phase partitioning behavior (in aq. Na 2 SO 4 , Na 3 PO 4 , and sodium dodecyl sulfate (SDS)), micellization, as well as the molecular dynamics simulation of the TTX-100 and MMH drug mixture have been examined. The cloud point (CP) values of TTX-100 + MMH system have been detected to be lessened with the growing concentration of Na 2 SO 4 and Na 3 PO 4 , where the CP values follow the order: CP (aq. Na 3 PO 4) < CP (aq. Na 2 SO 4). The introduction of SDS caused the enhancement of CP for the study system. The critical micelle concentration (CMC) for the TTX-100 + MMH mixture was determined using the absorbance vs. log [TTX-100] plot using the UV–Visible spectroscopic tool. The CMC values were attained to be heightened with the rising content of MMH and, thus, the presence of MMH disfavors the micelle growth of TTX-100. The free energy changes of clouding (Δ G c 0) and micellization (Δ G b 0) have been noticed as positive (nonspontaneous process) and negative (spontaneous process), respectively. The changes in standard enthalpy (Δ H c 0), entropy (Δ S c 0), thermodynamic transfer parameters (Δ G c , t r 0 , Δ H c , t r 0 , Δ S c , t r 0), and the Δ H c 0 - Δ S c 0 compensation factors were also computed and appropriately explained. The values of Δ H c 0 and Δ S c 0 recommend that the clouding of TTX-100 + MMH in aq. Na 2 SO 4 and Na 3 PO 4 is controlled by the enthalpy alone, while the process is controlled by the entropy in aq. SDS solution. In this process, the electrostatic interactions and hydrophobic force are recommended as core forces among the employed media. By applying the molecular dynamics simulation, the atomic-scale interactions between MMH and TTX-100 were unveiled, showing a strong correlation with the experimental outcomes. [ABSTRACT FROM AUTHOR]

Biochemicals are widely used in the medicine and food industries and are more efficient and safer than synthetic chemicals. The amphipathic surfactants can interact with the microorganisms and embed the extracellular metabolites, which induce microbial metabolites secretion and biosynthesis, performing an attractive prospect of promoting the biochemical production. However, the commonness and differences of surfactant-mediated bio-manufacture in various fields are largely unexplored. Accordingly, this review comprehensively summarized the properties of surfactants, different application scenarios of surfactant-meditated bio-manufacture, and the mechanism of surfactants increasing metabolites production. Various biochemical productions such as pigments, amino acids, and alcohols could be enhanced using the cloud point and the micelles of surfactants. Besides, the amphiphilicity of surfactants also promoted the utilization of fermentation substrates, especially lignocellulose and waste sludge, by microorganisms, indirectly increasing the metabolites production. The increase in target metabolites production was attributed to the surfactants changing the permeability and composition of the cell membrane, hence improving the secretion ability of microorganisms. Moreover, surfactants could regulate the energy metabolism, the redox state and metabolic flow in microorganisms, which induced target metabolites synthesis. This review aimed to broaden the application fields of surfactants and provide novel insights into the production of microbial biochemicals. [ABSTRACT FROM AUTHOR]

Biodiesel is viewed as the alternative to petroleum diesel, but its poor low-temperature performance constrains its utilization. Cloud point (CP), the onset temperature of thermal crystallization, appropriately shows the low-temperature performance. The effective way to reduce CP is to remove saturated fatty acid methyl esters (FAMEs). Compared to current methods, this work describes an extraordinary approach to fractionating FAMEs by forming solid urea inclusion compounds (UICs). Urea inclusion fractionation reduces the CPs by removing high melting-point linear saturated FAME components. Urea inclusion fractionation in this study was performed under various processing conditions: mass ratios of urea to FAMEs and solvents to FAMEs, various solvents, FAMEs from various feedstocks, and processing temperatures. Supersaturation of urea in the solution is the driving force, and it significantly affects yield, composition, CP, separation efficiency, and selectivity. Through a single urea inclusion fractionation process, FAMEs, except palm oil FAMEs, resulted in CP reduction ranging from 20 to 42 °C with a yield of 77-80% depending on the compositions. CP of palm oil FAMEs could reach as low as -17 °C with a yield of 46% after twice urea inclusion fractionation. According to the model prediction, the cetane number after urea inclusion fractionation decreased about 0.7-2 but was still higher than the minimum biodiesel requirement. Oxidation stability after urea inclusion decreased according to the proposed model, but this can be mitigated by adding antioxidants. Emission evaluation after urea inclusion fractionation indicated decreased hydr°Carbons, carbon monoxide, and particulate matter. However, it resulted in the increasing emission of nitrogen oxides. [ABSTRACT FROM AUTHOR]

The topology effects of cyclization on thermal phase transition behaviors were investigated for a series of amphiphilic Pluronic copolymers of both hydrophilic–hydrophobic–hydrophilic and hydrophobic–hydrophilic–hydrophobic block sequences. The dye solubilization measurements revealed the lowered critical micelle temperatures (TCMT) along with the decreased micellization enthalpy (ΔHmic) and entropy (ΔSmic) for the cyclized species. Furthermore, the transmittance and dynamic light scattering (DLS) measurements indicated a block sequence-dependent effect on the clouding phenomena, where a profound decrease in cloud point (Tc) was only found for the copolymers with a hydrophilic–hydrophobic–hydrophilic block sequence. Thus, the effect of cyclization on these critical temperatures was manifested differently depending on its block sequence. Finally, a comparison of the linear hydroxy-terminated, methoxy-terminated, and cyclized species indicated the effect of cyclization to be unique from a simple elimination of the terminal hydrophilic moieties. [ABSTRACT FROM AUTHOR]

Until quite recently, Arctic diesel fuel was produced in accordance with GOST R 55475 with a cold filter plugging point down to –52°C using a depressant-dispersing additive. However, in the Arctic, the temperature drops to –60°C and below, and the use of depressant-dispersing additives provokes product stratification with a sharp deterioration in the properties of the lower layer. This limited the application of Arctic diesel fuel in the Arctic. For such conditions, the Ministry of Defense of the Russian Federation developed its own standards for Arctic diesel fuel without the use of depressant-dispersing additives, and suggesting values not higher than –65°C for the cloud point, pour point and cold filter plugging point. An obstacle for obtaining a product with such properties is the difficulty of simultaneously providing the required cetane number and the low temperature properties. This paper presents a method for obtaining Arctic diesel fuel with the desired properties based on deeply isomerized diesel fractions. To implement the project, the existing units at Slavneft-YANOS PJSC were analyzed, and a chain of units was assembled for primary oil refining, hydrotreating 80 atm and isodewaxing. In the course of a number of experiments new causes of the onset of cold filter plugging point were discovered, which were explained by an increase in the diesel fuel viscosity at extremely low temperatures. To reduce the viscosity of the product, hydrocracked kerosene was added to the formula. In May 2020, permits were received from the Ministry of Defense of the Russian Federation, and in October 2021, for the first time in the Russian Federation and in the world, the first industrial batch of 3,000 tons was successfully produced. [ABSTRACT FROM AUTHOR]

Among alternative transport fuels, biodiesel is an eco-friendly substitute for petrodiesel. The quality of biodiesel is dependent on the composition of feedstock oils used for its preparation. The mathematical/statistical tools are used to determine the biodiesel properties, and their outputs are further compared with experimental results for their consistency and reliability. To reduce the cost, efforts and resources, the current study aims to evaluate the predicting ability of the standalone software BiodieselAnalyzer. In the present study, properties of 45 biodiesels are predicted using BiodieselAnalyzer software and the obtained results are compared with earlier published literature. The % absolute relative deviation was found as 4.47% and 5.31% for density and higher heating value, respectively, but the highest deviation was found for kinematic viscosity (70.19%), oxidation stability (131.19%), cloud point (118.57%) and cold filter plugging point (234.17%). The results indicate that the software shows a good performance in predicting the density and higher heating value; however, the software shows poor reliability in predicting kinematic viscosity, oxidation stability, cloud point and cold filter plugging point. This inconsistency might be due to the non-inclusion of factors such as minor oil components, natural antioxidant in oil, oil extraction process, storage conditions of oil, impurities in oil, production processes, oil and biodiesel clean-up process. Based on this work, it is recommended to improve/develop the software in terms of accuracy and precision for predicting the biodiesel properties or adopt experimentation to determine biofuel properties. [ABSTRACT FROM AUTHOR]