Mixture Of Glycerol Research Articles

Development of a Biodegradable Cassava Starch Biofilm based on a Combination of Plasticizers with Bio‐SiO2 Extracted from Sugarcane Leaves

AbstractThis study prepares biodegradable biofilms for packaging applications from biomass to help reduce plastic waste while also adding value to biomass. Furthermore, the effects of plasticization with 30 wt% plasticizer (relative to the mass of cassava starch) by glycerol (G), sorbitol (S), and a mixture of glycerol and sorbitol (GS) plasticizers are investigated, and the effects of bio‐SiO2 particles extracted from sugarcane leave via the sol–gel method are evaluated in terms of the mechanical and biodegradability properties of the cassava starch‐based biofilms. Biofilms used for packing applications must be insoluble and exhibit good elongation properties. In this context, the results indicate that the GS mixture produces a biofilm that exhibits these desirable properties. Thus, cassava starch‐based biofilms are prepared using GS and varying concentrations of the bio‐SiO2 particles (i.e., 0, 0.5, 1, and 1.5 wt%). The films containing bio‐SiO2 exhibit significantly lower water solubilities and moisture contents than the corresponding bio‐SiO2‐free films. Additionally, the inclusion of bio‐SiO2 particles increases the water resistance properties of the biofilms. Overall, the results suggest that cassava starch films prepared using a mixture of plasticizers and reinforced with bio‐SiO2 particles can be considered a safe material for application in biodegradable food packaging.

Preparation and properties of chitosan/gelatin film containing capsaicinoid for hemostasis and antibacterial

Blood loss resulting from accidents or surgery is a worrying health problem. This is because hemorrhage can occur and cause death. Therefore, the development of safe and effective hemostatic materials is important. Hemostatic agents (Ha) made from the composite of chitosan, gelatin, and glycerol mixtures and capsaicinoids (Cap) at various compositions 0, 1, 2, 4, 6 and 12 wt%. The films forming were prepared by casting with the aim of obtaining an environmentally friendly material for intraoperative hemostasis. The characterizations of the samples were performed by physicochemical, morphological, hemostasis test, functional groups, antibacterial, and mechanical properties were evaluated. The samples received are flexible and transparent. It was found that 6 wt% Cap showed the optimization in stopping bleeding, and Cap content of 12 wt% was optimized for antibacterial properties both Staphylococcusaureus and Escherichia coli. The results show that the addition Cap into chitosan/gelatin film based Ha has high potential as a hemostatic product, and there is a very interesting trend in the development of hemostatic and antibacterial materials in the future.

Towards direct superlubricity and negligible wear with polyalcohol lubricant mixtures of ethylene glycol and glycerol for steel tribopairs

Friction and wear remain as the main concerns in the mechanical mobility systems due to the significant energy consumption and the main mode of component failures, and achieving direct superlubricity has attracted enormous attention by fundamentally minimizing friction and wear. In this work, we have prepared polyalcohol lubricant mixtures of ethylene glycol and glycerol to precisely enhance the in-situ formation of passivation film on the friction surfaces, and remarkable direct superlubricity of 0.0057 combined with negligible wear has been successfully achieved at ethylene glycol/glycerol weight ratio of 0.6 for steel tribopairs. Lubrication state analysis indicates that the achieved superlubricity state is in the boundary lubrication regime, and further adsorption analysis indicates that there is a strong interaction between lubricant molecules and friction surfaces via the hydroxyl groups. A sliding simulation of polyalcohol lubricant mixtures of ethylene glycol and glycerol indicates that ethylene glycol could be induced to accumulate near the friction surfaces to form easy-to-shear layers. Furthermore, both the experimental analysis and the molecular dynamics simulation demonstrate that a tribochemical reaction could be induced for the lubricant molecules at the interface, with water molecules formed to further strengthen the formation of easy-to-shear layers and oligomers formed to more effectively passivate the asperity contacts. This work provides a new strategy to direct liquid superlubricity and could advance the application of liquid superlubricity in the industry field.

Improving Aerosol Characterization Using an Optical Particle Counter Coupled with a Quartz Crystal Microbalance with an Integrated Microheater.

Aerosols, as well as suspended particulate matter, impact atmospheric pollution, the climate, and human health, directly or indirectly. Particle size, chemical composition, and other aerosol characteristics are determinant factors for atmospheric pollution dynamics and more. In the last decade, low-cost devices have been widely used in instrumentation to measure aerosols. However, they present some issues, such as the problem of discriminating whether the aerosol is composed of liquid particles or solid. This issue could lead to errors in the estimation of mass concentration in monitoring environments where there is fog. In this study, we investigate the use of an optical particle counter (OPC) coupled to a quartz crystal microbalance with an integrated microheater (H-QCM) to enhance measurement performances. The H-QCM was used not only to measure the collected mass on its surface but also, by using the integrated microheater, it was able to heat the collected mass by performing heating cycles. In particular, we tested the developed system with aerosolized saline solutions of sodium chloride (NaCl), with three decreasing concentrations of salt and three electronic cigarette solutions (e-liquid), with different concentrations of propylene glycol and glycerin mixtures. The results showed that the OPC coherently counted the salt dilution effects, and the H-QCM output confirmed the presence of liquid and solid particles in the aerosols. In the case of e-liquid aerosols, the OPC counted the particles, and the HQCM output highlighted that in the aerosol, there were no solid particles but a liquid phase only. These findings contribute to the refinement of aerosol measurement methodologies by low-cost sensors, fostering a more comprehensive understanding.

A Low Transition Temperature Mixture-based viscosupplementation complemented with celecoxib for osteoarthritis treatment

Viscosupplementation consists of hyaluronic acid (HA) intra-articular injections, commonly applied for osteoarthritis treatment while non-steroidal anti-inflammatory drugs (NSAIDs) are widely administered for pain relief. Here, HA and a NSAID (celecoxib) were combined in a formulation based on a low transition temperature mixture (LTTM) of glycerol:sorbitol, reported to increase celecoxib’s solubility, thus rendering a potential alternative viscosupplement envisioning enhanced therapeutic efficiency. The inclusion of glucosamine, a cartilage precursor, was also studied. The developed formulations were assessed in terms of rheological properties, crucial for viscosupplementation: the parameters of crossover frequency, storage (G’) and loss (G’’) moduli, zero-shear-rate viscosity, stable viscosity across temperatures, and shear thinning behaviour, support viscoelastic properties suitable for viscosupplementation. Additionally, the gels biocompatibility was confirmed in chondrogenic cells (ATDC5). Regarding drug release studies, high and low clearance scenarios demonstrated an increased celecoxib (CEX) release from the gel (6 to 73-fold), compared to dissolution in PBS. The low clearance setup presented the highest and most sustained CEX release, highlighting the importance of the gel structure in CEX delivery. NMR stability studies over time demonstrated the LTTM+HA+CEX (GHA+CEX) gel as viable candidate for further in vivo evaluation. In sum, the features of GHA+CEX support its potential use as alternative viscosupplement.

Sintesis Biodiesel Dari Minyak Jelantah Dalam Reaktor Ultrasonik

Waste cooking oil is considered promising alternative to biodiesel production as substitute for diesel fuel becauce it it is environmentally friendly, biodegradable, non-toxic, and renewable energy source. This study aims to obtain the optimum operating conditions of ultrasonic reactors in biodiesel production using Response Surface Methodology (RSM) method. RSM with CCD was used to determine effect of transducer distance (1-5 cm) and reaction time (5-20 minutes) on biodiesel yield, to determine optimal operating conditions and to optimize biodiesel yield. In this study, waste cooking oil was transesterified into biodiesel with ultrasonic waves to intensify reaction. Transesterification waste cooking oil was carried out in a sodium hydroxide catalyst using methanol. Solution inserted into the erlenmeyer with the transducer distance and reaction time to determined by RSM. Once the reaction time was reached, mixture of biodiesel and glycerol was separated in separate funnel. Biodiesel obtained was then washed and evaporated the remaining solvent. Biodiesel yield was obtained under 88.33% under optimal conditions of 1 cm transducer distance with reaction time 20 minutes. Reaction time was the most important parameter based on the ANOVA test. The properties biodiesel produced including kinematic viscosity, density, acid number, methyl ester contents and monoglicerida have met the requirements of standards SNI 7182: 2015.

Interfacial Nanostructure and Hydrogen Bond Networks of Choline Chloride and Glycerol Mixtures Probed with X-ray and Vibrational Spectroscopies.

The molecular distribution at the liquid-vapor interface and evolution of the hydrogen bond interactions in mixtures of glycerol and choline chloride are investigated using X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Nanoscale depth profiles of supersaturated deep eutectic solvent (DES) mixtures up to ∼2 nm measured by ambient-pressure XPS show the enhancement of choline cation (Ch+) concentration by a factor of 2 at the liquid-vapor interface compared to the bulk. In addition, Raman spectral analysis of a wide range of DES mixtures reveals the conversion of gauche-conformer Ch+ into the anti-conformer in relatively lower ChCl concentrations. Finally, the depletion of Ch+ from the interface (probing depth = 0.4 nm) is demonstrated by aerosol-based velocity map imaging XPS measurements of glyceline and water mixtures. The nanostructure of liquid-vapor interfaces and structural rearrangement by hydration can provide critical insight into the molecular origin of the deep eutectic behavior and gas-capturing application of DESs.

Regulation of metabolism and proton motive force generation during mixed carbon fermentation by an Escherichia coli strain lacking the FOF1-ATPase

Proton FOF1-ATPase is the key enzyme in E. coli under fermentative conditions. In this study the role of E. coli proton ATPase in the μ and formation of metabolic pathways during the fermentation of mixture of glucose, glycerol and formate using the DK8 (lacking FOF1) mutant strain was investigated. It was shown that the contribution of FOF1-ATPase in the specific growth rate was ∼45 %. Formate was not taken up in the DK8 strain during the initial hours of the growth. The utilization rates of glucose and glycerol were unchanged in DK8, however, the production of succinate, lactate and ethanol was decreased causing a reduction of the redox state up to −450 mV. Moreover, the contribution of FOF1-ATPase in the interplay between H+ and H2 cycles was described depending on the bacterial growth phase and main utilizing substrate. Besides, the H2 production rate in the DK8 strain was decreased by ∼60 % at 20 h and was absent at 72 h. Δp was decreased from −157 ± 4.8 mV to −140 ± 4.2 mV at 20 h and from −195 ± 5.9 mV to −148 ± 4.4 mV at 72 h, compared to WT. Taken together it can be concluded that during fermentation of mixed carbon sources metabolic cross talk between FOF1-ATPase-TrkA-Hyd-Fdh-H is taking place for maintaining the cell energy balance via regulation proton motive force.

ZnO–Doped CaO Binary Core–Shell Catalysts for Biodiesel Production via Mexican Palm Oil Transesterification

This work investigates biodiesel production via transesterification of Mexican palm oil with methanol catalyzed by binary solid base core–shell catalysts with improved catalytic stability. A series of CaO–ZnO mixed solids were prepared using an inexpensive co–precipitation method by varying ZnO content from 5 to 20 mol%. Several factors, such as surface basicity, ZnO content, phase compositions, and thermal treatment of the catalysts, were all proven to be crucial for the production of biodiesel with good quality. Thermal treatment could effectively remove the surface adsorbed water and impurities and improved the catalytic activity. The addition of ZnO to CaO significantly enhanced the catalysts’ stability; however, it led to lower surface basicity and slightly diminished catalytic activity. ZnO doping inhibited the formation of surface Ca(OH)2 and promoted the formation of Ca–Zn–O or CaZn2(OH)6 phase as the core and a surface CaCO3 shell, which effectively decreased Ca2+ leaching by approximately 74% in methanol and 65% in a methanol–glycerol (4:1) mixture. A combined method of separation and purification for obtaining clean biodiesel with high quality was proposed. The biodiesel obtained under the control conditions exhibited properties which satisfied the corresponding standards well.

Determination of Electrical and Mechanical Properties of Liquids Using a Resonator with a Longitudinal Electric Field

The possibility of determining the elastic modules, viscosity coefficients, dielectric constant and electrical conductivity of a viscous conducting liquid using a piezoelectric resonator with a longitudinal electric field is shown. For the research, we chose a piezoelectric resonator made on an AT-cut quartz plate with round electrodes, operating with a shear acoustic mode at a frequency of about 4.4 MHz. The resonator was fixed to the bottom of a 30 mL liquid container. The samples of a mixture of glycerol and water with different viscosity and conductivity were used as test liquids. First, the frequency dependences of the real and imaginary parts of the electrical impedance of a free resonator were measured and, using the Mason electromechanical circuit, the elastic module, viscosity coefficient, piezoelectric constant and dielectric constant of the resonator material (quartz) were determined. Then, the container was filled with the test sample of a liquid mixture so that the resonator was completely covered with liquid, and the measurement of the frequency dependences of the real and imaginary parts of the electrical impedance of the loaded resonator was repeated. The dependences of the frequency of parallel and series resonances, as well as the maximum values of the electrical impedance and admittance on the conductivity of liquids for various viscosity values, were plotted. It was shown that these dependences can be used to unambiguously determine the viscosity and conductivity of the test liquid. Next, by fitting the theoretical frequency dependences of the real and imaginary parts of the electrical impedance of the resonator loaded with the liquid under study to the experimental dependences, the elastic module of the liquid and its dielectric constant were determined.

Equilibrium solubility determination, modeling and thermodynamic analysis of isophthalic acid in aqueous co-solvent mixtures of propylene glycol, ethylene glycol and glycerol

Equilibrium solubility determination, modeling and thermodynamic analysis of isophthalic acid in aqueous co-solvent mixtures of propylene glycol, ethylene glycol and glycerol

Increasing the Pentose Phosphate Pathway Flux to Improve Plasmid DNA Production in Engineered E. coli.

The demand of plasmid DNA (pDNA) as a key element for gene therapy products, as well as mRNA and DNA vaccines, is increasing together with the need for more efficient production processes. An engineered E. coli strain lacking the phosphotransferase system and the pyruvate kinase A gene has been shown to produce more pDNA than its parental strain. With the aim of improving pDNA production in the engineered strain, several strategies to increase the flux to the pentose phosphate pathway (PPP) were evaluated. The simultaneous consumption of glucose and glycerol was a simple way to increase the growth rate, pDNA production rate, and supercoiled fraction (SCF). The overexpression of key genes from the PPP also improved pDNA production in glucose, but not in mixtures of glucose and glycerol. Particularly, the gene coding for the glucose 6-phosphate dehydrogenase (G6PDH) strongly improved the SCF, growth rate, and pDNA production rate. A linear relationship between the G6PDH activity and pDNA yield was found. A higher flux through the PPP was confirmed by flux balance analysis, which also estimates relevant differences in fluxes of the tricarboxylic acid cycle. These results are useful for developing further cell engineering strategies to increase pDNA production and quality.

Enhancing the catalytic properties of silicalite-1 through ammonium fluoride modification for waste glycerol acetalization.

Silicalite-1 is a silica with a zeolitic MFI (Mobil Five) structure devoid of noticeable catalytically active (e.g., acid) sites. In this study, we present its modification with NH4F solutions of varying concentrations (0.5-3 M), which generates efficient and selective acid sites for the acetalization of glycerol with acetone towards solketal (2,2-dimethyl-1,3-dioxolane-4-methanol). The creation of acid sites is attributed to the partial elimination of external silanol groups in silicalite-1 and the generation of some framework defects, resulting also in increased porosity. The characterization of the modified materials was performed using various techniques, i.e. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), temperature-programmed desorption of ammonia (TPD-NH3), and Fourier-transform infrared spectroscopy (FTIR). The results demonstrate that the newly created acidic sites of Brønsted and Lewis nature exhibit significantly higher acidic strength and enhanced accessibility for reagents compared to the pristine one, resulting in exceptional glycerol conversion in the acetalization of glycerol with acetone and notable selectivity towards solketal. Glycerol conversion over modified silicalite-1 reached nearly 70%, with the selectivity to solketal exceeding 98% at 70° C after 1 hour of reaction time, using a mixture of glycerol and acetone in a 1 : 1 ratio. The proposed reaction mechanism takes into account a combination of Brønsted and Lewis acid sites. The obtained results indicated that Brønsted acid sites, especially those of higher strength, are the most beneficial in this process. The remarkable catalytic performance and stability of modified silicalite-1 make it a promising candidate for potential industrial applications in the utilization of waste glycerol formed in the biofuel industry.

ИССЛЕДОВАНИЕ ТЕПЛООБМЕНА В АППАРАТАХ С ПЕРЕМЕШИВАЮЩИМ УСТРОЙСТВОМ

This study was carried out with the aim of in-depth analysis of heat transfer processes in chemical and heat apparatuses that use mixing devices. The mixing process plays a key role in various industries, including chemical production, food processing and many others. Mixing is important for uniform distribution of components in reactors, tanks and apparatus, which in turn affects product quality and process efficiency. Heat exchange is a vital element in numerous technological processes and holds a significant role in enhancing efficiency and conserving energy across various industries. This study began with a thorough review of the literature. Further experiments were carried out, including work with different types of apparatuses and stirring devices, with different stirring intensity. Digital prototypes were chosen as the method of research and the ANSYS software package was used. The purpose of this study is to analyze the efficiency of heat transfer in such apparatuses, as well as to identify the factors affecting the intensity of heat transfer. This study addresses following problems: heating water in an apparatus with a stirrer, determining the critical temperature and time to reach steady-state in different mixtures. The study of heat transfer in apparatus with a mixing device is a critical element for optimizing production processes and increasing energy efficiency. According to calculations, faster achievement of the steady-state regime is observed, which indicates more efficient heating of the liquid when using a turbine stirrer. Mathematical calculations confirm that when stirring a mixture of water and glycerin, compared to stirring pure water, a slower and less efficient heating process occurs, due to the higher viscosity of glycerin. This study serves as an important contribution to the field of heat transfer and provides valuable guidelines for further developments and applications.

Vapor-Liquid Equilibrium Measurement of Systems Containing Glycerol for Separation Process of Glycerol as a By-Product of Biodiesel

The most popular technique to produce biodiesel were uses alcohol as a catalyst to transesterify triglycerides. The biodiesel transesterification process has a by-product in the form of glycerol which has a high selling value. Equilibrium data of glycerol and alcohol mixtures is limited in equilibrium conditions and systems which causes the glycerol purification process may not be designed and operated optimally. This research aims to obtain experimentally isobaric vapor-liquid equilibrium of methanol + glycerol binary system at 31.3, 61.3, and 100.8 kPa. A modified Glass Othmer-Still was utilised to carry out the experiment. Refractometer index type Bausch and Lomb ABBE was used to examine the equilibrium composition of the liquid and vapor phases. Using the L-W thermodynamic consistency test method, the experimental data used in this work were shown to be thermodynamically consistent. The experimental data were correlated well with the Wilson, Non-Random Two Liquid (NRTL), and Universal Quasi-Chemical (UNIQUAC) models with absolute average deviation in temperatures (AADT) and that in vapor compositions (AADy) smaller than 0.3% and 0.2%, respectively. The Universal Chemical Functional Group Activity Coefficient (UNIFAC) in predicting VLE the system studied showed good performance giving AADT and AADy smaller than 7.4% and 0.04%, respectively.

Structure and dynamics in aqueous mixtures of glycerol: insights from molecular dynamics simulations.

Aqueous glycerol mixtures are investigated over the whole concentration range of glycerol xGLY = 0.1-0.9 via molecular dynamics (MD) simulations at ambient pressure and temperature. Two glycerol force fields are used: an all-atom (AA) and a united-atom (UA) model. Structural changes upon different mixing ratios are discussed through the site-site radial distribution functions (RDFs), coordination numbers and cluster analysis. As both species are hydrogen bonded, they form an almost perfect H-bonded network, with no observed clusters. There are, however, noticeable changes in the RDFs. Glycerol correlations grow stronger with increasing glycerol content, as do water correlations. There is significant transformation in dynamics as well, as evidenced by the self-diffusion coefficients, the velocity autocorrelation functions and the rotational autocorrelation functions. Diffusion of both species slows down with increasing glycerol content. Rotational relaxation is also altered depending on the mixture composition and there is a slow-down at the lower end of glycerol content.

Control of skin damages caused by oxidative stress using mangiferin and naringin co-loaded in phospholipid vesicles

Mangiferin and naringin, two naturally occurring antioxidant molecules, were co-loaded in phospholipid vesicles designed for skin delivery. Ultradeformable-liposomes containing tween 80 as edge activator, were used as basic formulation, which was modified adding glycerol (glycerosomes) or a mixture of glycerol and ethanol (et-glycerosomes) and further enriched with a polymer, sodium hyaluronate (glycerohyalurosomes and et-glycerohyalurosomes), to evaluate the role of vesicle composition on their features and performances. Mean dimeter, polydispersity index and zeta potential of prepared vesicles were measured along with their stabilitcay on storage for 90 days, rheological behavior and suitability as systems for the delivery of these active molecules into and through the skin. Vesicles enriched with sodium hyaluronate were the most stable and the smallest and favored the deposition of both mangiferin and naringin in the whole skin, in a better extent than those without polymer. All the vesicles were highly biocompatible and capable of protecting fibroblasts against hydrogen peroxide-induced oxidative damages in vitro. Once more, glycerohyalurosomes and et-glycerohyalurosomes where those which improved the most the beneficial effect of mangiferin and naringin, as they were capable of effectively counteracting the formation of skin lesion, or even promoting the wound healing, thanks to their greater ability to inhibit both myeloperoxydase activity and oedema formation in vivo in a model mouse in which wound was induced using phorbol acetate.

Physico-chemical characterisation of glycerol- and ethylene glycol-based deep eutectic solvents

Deep eutectic solvents are of significant interest to numerous applications including cryopreservation, chemical synthesis, lubrication, energy storage, catalysis, and self-assembly. However, to date there have been few rigorous and systematic studies of the physico-chemical and thermal properties of these solvents. This means that conclusive structure-function relationships are difficult to define within the context of the current literature. Here, we present the viscosity, refractive index, density, surface tension, and thermal behaviour of mixtures of either glycerol or ethylene glycol with choline chloride, betaine, or L-proline, as neat fluids and in the presence of water. We demonstrate that changing the ratio of hydrogen bond donor to hydrogen bond acceptor has only a small effect on the physico-chemical properties, while the addition of even small quantities of water has a significant effect. Despite rigorous studies, we demonstrate that determining the eutectic point of these mixtures is not straight-forward and that the definition of a ‘deep’ eutectic solvent may need to be reviewed in the frame of ideal mixing theory.

Enhancement of ultrasonic-assisted extraction and antioxidant potential of phenolic compounds from Moroccan Cannabis sativa: A green intelligent approach integrating optimal mixture process design and artificial neural networks

Environmentally-friendly extraction methods enables both efficient extraction of phenolic compounds from plant sources and safe use of the extracted substances. These characteristics render them as ideal choices for sustainable extraction processes. This study combines a green and sustainable extraction strategy with an intelligent statistical approach to optimize the recovery and the antioxidant activity of phytochemicals derived from Moroccan Cannabis sativa. The optimization of the ultrasound-assisted extraction is achieved using an optimal mixture-process design (OMPD) combined with artificial neural networks (ANNs). The OMPD consists of a mixture of water, glycerol, and ethanol, along with process parameters such as processing time, solvent-to-material (S/M) ratio, and temperature. The objective is to optimize the five responses extraction yield, total phenolic content (TPC), and antioxidant activities measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH), total antioxidant capacity (TAC), and Ferric reducing antioxidant power (FRAP) assays. The results of the OMPD indicate that the recovery of phenolic compounds and antioxidant activity can be improved by using a binary mixture of water and ethanol, along with moderate processing time and temperature, and a high S/M ratio. The optimal responses were 26.06 %, 92.6 mg GAE/g, 0.1 mg/ml, 298 mg AAE/g, and 1.3 mg/ml for yield, TPC, TFC, DPPHIC50, TAC, and FRAPEC50, respectively. Subsequently, the OMPD matrix was used as input for the ANNs, employing a 6-6-5 multi-layer perceptron design. The findings of the ANNs closely matched those obtained from the OMPD models. However, the performance parameters of the ANNs models were slightly superior to those of the OMPD.

Energy exchange during the early phase of droplet impact onto a dry surface

This study investigates droplet impact dynamics on a rigid substrate using droplets of water and water–glycerol mixtures. Experiments are conducted in the Weber number range of 179–929, and the corresponding Reynolds numbers are in the range of 5253–12 090. The profile of the droplet interface is studied. Assuming self-similarity in the internal flow at the interface of the droplet, the profiles are scaled using appropriate scales. It is observed that the profiles of the droplet interface (at different points of time) collapse close to each other when plotted in this manner. This observation serves as an experimental evidence to the self-similarity of the internal flow in this phase. Based on this fact, we make an estimate of kinetic energy at early stages of droplet impact. The surface energy is also estimated by assuming axisymmetry in the droplet profile obtained through back-light imaging. We observe that a considerable amount of the kinetic energy is lost during the early stages of droplet impact. We believe that an accurate estimation of this deficit in kinetic energy at an early stage of impact will be necessary to account in the energy based models for droplet impact.