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Stabilization of an oil phase is crucial in many industrial processes. SAXS quantifies the ordering of nanoparticles on Pickering emulsion droplets, stabilized by complex amphiphilic Interactions.

Understanding the deposition pattern formed by an evaporated colloidal drop is of fundamental and technological interest. Such an evaporative process is important in various applications starting from inkjet printing to disease diagnosis. In this work, it is shown that the deposit pattern on a porous membrane can be tuned by varying the colloidal viscosity and membrane pore size. We have used small-angle X-ray scattering (SAXS) in scanning mode for profiling of deposit morphology and also for estimation of the interparticle correlation. It is demonstrated that low viscosity and small pore size favor a centrally dipped pattern owing to the coffee ring effect, which can be modified to a contrasting centrally peaked pattern by increasing the viscosity and pore size. To comprehend the experimental observations, a computer model has been developed using a continuity equation that well corroborates the experimental observations on the final deposited pattern and also provides the time evolution of the pattern. The work provides a way to tune the pattern of colloidal stain on a porous substrate by controlling flow and absorption.

The packing of particles is ubiquitous, and it is of fundamental importance, particularly in materials science in the nanometric length scale. It becomes more intriguing when constituent particles deviate from spherical symmetry owing to the inherent complexity in quantifying their positional and rotational correlation. For quantitative estimation of packing fraction, it requires a thorough analysis of the positional correlation of jammed particles. This article adopts a novel approach for determination of the packing fraction of strongly correlated nano-ellipsoids in a microsphere using small-angle scattering. The method has been elucidated through a quantitative analysis of structural correlation of nano-hematite ellipsoids in 3D micrometric granules, which are realized using rapid evaporative assembly. Owing to the deviation from spherical symmetry, the conventional analysis of scattering data fails to interpret the actual packing fraction of the anisotropic particles. The structural correlation gets smeared out because of orientation distribution among the packed anisotropic particles, which leads to an anomaly in the estimation of packing fraction using the conventional analysis approach. It is illustrated that consideration of an interparticle distance distribution function of the correlated nano-ellipsoids becomes indispensable in determining their packing fraction.

An immiscible interface across aqueous droplets has been utilized to achieve hollow TiO2 and TiO2/SiO2 composite microspheres which show superior photocatalytic characteristics.

Solid amine-based nano-adsorbents have shown tremendous potential for mitigating CO2 emissions.

Recently emerged lead-halide perovskite nanocrystals (PNCs) are promising optoelectronic material due to their easy solution processability, wide range of color tunability, as well as very high photoluminescence quantum yield. Despite their significant success in lab-scale optoelectronic applications, the long-term stability becomes the main issue, hindering them towards commercialization. The highly ionic nature of such lead-halide structure makes them extremely unstable in water and air. But a very few groups have taken the advantage of such nature of the crystal structure for water-triggered chemical transformation towards shape, composition, and morphology controlled stable and bright PNCs, which are otherwise difficult to obtain by typical direct approach. Furthermore, using polymer as an encapsulating layer for the PNCs, water-soluble stable PNCs have been prepared. In this review, the recent progress on the water-hexane interface chemistry towards chemical transformation to produce several PNCs is described. Such method not only ensure to yield several shape-controlled perovskites nanocrystals, but also formation of perovskites in aqueous phase that show promising application towards bio-imaging.

Titania (TiO

Objective: The study was planned primarily to judge the effectiveness, safety, and adherence of the prescribed treatments in dermatophytosis along with the effect on the Quality of Life (QoL) of the affected individuals. Methods: In this prospective observational study, spanning over 5 months, participants (dermatophytosis patients) were assessed at baseline and 6 week-follow-up at study site. Information about their clinical presentation, QoL (Quality of Life) parameters, medication adherence, and adverse drug reaction (ADR) were entered in the Case Report Form (CRF) prepared by utilizing global standard tools such as 5D-itch scale, Dermatology Life Quality Index (DLQI), Medication Adherence Rating Scale (MARS), and WHO-ADR reporting form respectively. Results: Total 60 subjects (33 males and 27 females) had completed the study. Overall, tinea cruris (40%) was the most common variety followed by combination of tinea corporis and cruris (35%), tinea corporis (20%), and tinea incognito (3%). Pruritus was the predominant symptom. There was a significant (p

A new method to estimate the size distribution of non-interacting colloidal particles from small-angle scattering data is presented. The method demonstrates that the distribution can be efficiently retrieved through features of the scattering data when plotted in the Porod representation, thus avoiding the standard fitting procedure of nonlinear least squares. The present approach is elaborated using log-normal and Weibull distributions. The method can differentiate whether the distribution actually follows the functionality of either of these two distributions, unlike the standard fitting procedure which requires a prior assumption of the functionality of the distribution. After validation with various simulated scattering profiles, the formalism is used to estimate the size distribution from experimental small-angle X-ray scattering data from two different dilute dispersions of silica. At present the method is limited to monomodal distributions of dilute spherical particles only.

Antihyperglycemic activity of leave extracts of Ficus carica was evaluated on STZ induced diabetic rats. Diabetes was induced in albino Wistar rats of either sex by intraperitoneal (60mg/kg b.w.) of STZ, freshly dissolved in citrate buffer (0.01 M, pH 4.5). Ficus carica leave extract in different solution (viz. petroleum ether, ethyloacetate, methanol and aqueous) were administered to diabetic rats for 9 days. The effect of extracts on blood glucose and body weight was studies on day 1st and 9th. The study showed that the ethyl acetate, methanolic and aqueous extract of Ficus sarmentosa leaves reduced blood glucose level and body weight significantly. This may justify the use of ficus species as ethanomedical medicine for treatment of diabetes mellitus.

The nano-crystalline mixed ferrites with the generic formula MnxMg1 − xFe2O4 (x = 0.0–1.0, step: 0.2) were prepared by the citrate-gel auto-combustion technique. Motivated by anomalous magnetic behaviour of coarse-grained MnFe2O4, the main aim was to study the influence of Mn2+ substitution in MgFe2O4 on magnetic structure at nano-regime. The compositional stoichiometry of the final ferrite products was ascertained by EDAX mapping and particle size for each sample was determined by powder X-ray diffraction, TEM, small-angle X-ray and neutron scattering techniques. The lattice constant increases with Mn-content due to larger cation (Mn2+) substitution. The distribution of cations in the tetrahedral (A) and octahedral (B) interstitial sites of the spinel lattice is determined by X-ray diffraction and Mossbauer spectral intensity analysis. The Mossbauer spectra at room temperature exhibit two sextets due to A- and B-sites for compositions x = 0.0, 0.2 and 1.0 while spectra showed central paramagnetic doublet superimposed on magnetic sextets for the samples with x = 0.4, 0.6 and 0.8, ascribed to the presence of superparamagnetic clusters. Thermal variation of AC susceptibility showed hump near the Curie temperature due to the presence of superparamagnetic clusters as corroborated by Mossbauer signature. The observed saturation magnetic moment (at temperature 5 K and applied field 9 T) is found lower compared to Neel's moment for the compositions with x > 0.2 which is explained on the basis of the exchange disorder of Fe3+ ions in the B-sites in Mn-containing ferrites.

A Small- and Wide-Angle X-ray Scattering (SWAXS) beamline (BL-18) is installed and commissioned at a 1.5 T bending magnet port (5°) of Indus-2 synchrotron at RRCAT, Indore, India. The ∼40-m-long beamline has tunable x-ray energy in the range of 5–20 keV by using a double crystal monochromator. A 1.5-m-long toroidal mirror is used to focus the x-ray beam at the detector position. The beamline is equipped with a 6-m-long movable detector stage to access different wave-vector transfer ranges. At present, an online image plate area detector and a linear position-sensitive gas detector are installed for Small-Angle X-ray Scattering (SAXS) and Wide-Angle X-ray Scattering (WAXS) measurements, respectively. The beamline is operational in simultaneous SAXS/WAXS mode to probe the mesoscopic as well as molecular level structure over a wide range of wave-vector transfer. The specification of the beamline and its performance are reported here. A few recent experimental results, as obtained from BL-18, are also described in brief.

The discovery of dendritic fibrous nanosilica (DFNS) has attracted great attention to the field of catalysis, CO2 capture, drug delivery due to its distinct morphology, and pore size distribution. Despite extensive research, the understanding of the DFNS formation process and its internal structure remains incomplete as microscopy and gas sorption techniques were not able to provide necessary in-depth structural information due to their inherent limitations. In the current work, we present a structural model of DFNS derived using small-angle X-ray scattering (SAXS) supported by 129Xe nuclear magnetic resonance (NMR), which provided intricate details of DFNS and its internal structure. Mechanistic understanding of the DFNS formation and growth process was achieved by performing time-resolved SAXS measurements during the synthesis of DFNS, which unveils the evolution of two levels of a bicontinuous microemulsion structure responsible for intricate DFNS morphology. The validity and the accuracy of the SAXS method and the model were successfully established through a direct correlation among the functionality of the DFNS scattering profile and its pore size distribution, as well as results obtained from the 129Xe NMR studies. It has been established that the DFNS structure originates from direct modulation of the bicontinuous structure controlled by a surfactant, a co-surfactant, and the silicate species formed during hydrolysis and the condensation reaction of the silica precursor.

In this work improved electroactive mesoporous Ag-doped bio-ceramics for medical usages are developed, examining their structural, electrical, in-vitro bioactivity, cell cultures and antibacterial properties against various classical pathogenic bacteria. Ag-containing mesoporous bio-ceramics (MBCs): xmol%Ag2O - (100-x)[45.8CaO-8.4B2O3-45.8SiO2] where x = 2, 5, 7.5 and 10 were synthesized through a sol-gel method. The small angle X-ray scattering and electron microscopy studies reveal the embedment of silver nanoparticles in the samples. Existence of silver as Ag+/Ag0 forms in the samples is confirmed by X-ray photoelectron spectroscopy. The N2 adsorption-desorption analysis evidence the mesoporous structure of the samples. The electrical conductivity of samples increases from 5.4 x 10−8 S cm−1 for x = 2 to 1.9 x 10−6 S cm−1 for x = 7.5 and then decreases to 0.9 x 10−6 S cm−1 for x = 10 at 110 °C. In vitro bioactivity studies revealed that Ag-containing MBCs hold the bone-like hydroxyapatite formation after immersion in human blood plasma like-solution such as Dulbecco's Modified Eagle's Medium. The antibacterial effect of samples against pathogenic bacteria (S. aureus, E. coli, P. monas aeruginosa, and B. cereus) increases with Ag concentration (x = 7.5) and then decreases with Ag content (x = 10). Antibacterial effect is greater for the sample with high electrical conductivity. The cell culture studies evidence not considerable cytotoxic effects for Ag-containing MBCs. Finally, the C2C12 myoblast cell culture studies reveal the significant cell growths and differentiation (myogenesis) for high electrical conducting Ag-containing MBCs.

This study aims to evaluate the characteristics of conditional volatility of the Indian stock market and compare the nature of volatility between the boom-and-bust phase of the Indian Financial cycle. The asymmetric volatility modelling is conducted using Exponential GARCH (EGARCH), Asymmetric power GARCH (APARCH) and GJR-GARCH on S&P Nifty 50 during July 2001 to June 2017 to arrest the nature of Indian financial cycle. We perform Value at Risk back-testing for adequacy of model fitness and compare half-life estimation for understanding the nature of persistence. Our study identifies APARCH (1,1) to be the best model for explaining boom phase volatility and EGARCH (1,1) as the best model for bust phase. The study also reveals the existence of inverse leverage effect in the boom-and-bust phase of the financial cycle. Our study originally contributes by comparing and documenting the empirical performance of GARCH processes during the boom-and-bust phase of Indian Financial Cycle. These empirical results would be beneficial for better risk management, portfolio optimisation and asset pricing.

Polymer-mediated interactions such as DNA-protein binding, protein aggregation, and filler reinforcement in polymers play crucial roles in many important biological and industrial processes. In this work, we report a detailed investigation of interactions between nanoparticles in the presence of high volume fractions of an adsorbing polymer. Small-angle X-ray scattering (SAXS) revealed the existence of a stable gel-like structure in the polymer-nanoparticle dispersion, whereby anchored polymer molecules on nanoparticles acted as bridging centres, while basic interactions between nanoparticles remained repulsive. Time-resolved SAXS measurements showed that the local volume fraction of nanoparticles increased during the drying of the dispersion owing to the shrinkage of the gel-like structure. Further, nanoparticle clusters in the dehydrated composite films showed percolated networks of nanoparticles, except for 5% loading that showed a phase-separated morphology as the volume fraction of nanoparticles remained lower than the percolation threshold. A significant restructuring of nanoparticle clusters occurred upon the hydration of nanocomposite films caused by the expansion of polymer networks induced by hydration forces. Temporal evolution of the volume fraction of nanoparticles during dehydration unveiled three distinct stages similar to the logistic growth function and this was attributed to the evaporation of free, intermediate, and bound water in the different stages. A plausible mechanism was elucidated based on the spring action analogy between anchored polymer chains and nanoparticles during hydration and dehydration processes.

Co-RGO nanocomposites are known to show interesting properties suitable for various applications. However, its use in the vital field of plasmonic nanocomposites is restricted as Co nanoparticles have high damping and dielectric loss. In this work, we have demonstrated a simple synthetic way to produce water-dispersible shape variant Co-reduced graphene oxide (RGO) hybrid nanocomposites, which can overcome those barriers and delineate two plasmonic peaks. Prepared multifunctional optical materials show both UV and visible range of plasmonic responses of Co NPs. While the single domain Co NPs show spin-up channel based sharp plasmonic peak in the UV range, the larger particles introduce shape-dependent enhancement of the excitation independent blue photoluminescence of graphene oxide (GO). Usually, due to their different size regime, it is not possible to see both UV and visible range plasmonic responses of Co NPs simultaneously. The variation of the Co particle size was deliberate to achieve multifunctionality. Shape-induced enhancement in the PL spectrum and decoration of plasmonic metal NPs are achieved. TEM micrographs of hybrids confirm the decoration of different shapes of Co nanoparticles on RGO sheets. The size distribution of the nanoparticles in the composites was quantified using two complementary techniques; SAXS/SANS and TEM. Scattering revealed the alteration of RGO agglomeration with the incorporation of differently shaped nanoparticles. Prepared hybrid nanocomposite having both the responses could be promising in magnetoplasmonics, GMR- and doping-based optoelectronics.

Time-resolved small-angle X-ray scattering (SAXS) measurements have been carried out using the newly developed SAXS beamline at the Indus-2 synchrotron source to study the evaporation-induced structural evolution of the lamellar mesophase. An aqueous dispersion of sodium dodecyl sulfate (SDS) of ∼0.60 volume fraction at room temperature results in a gel phase due to random jamming of the lamellar structured entities. Thermal analysis of SDS in the powder phase shows three distinct phenomena corresponding to evaporation of free and bound water, followed by thermal dissociation of SDS molecules. Time-resolved in situ SAXS measurements during evaporation of the gel under ambient conditions reveal two regimes of structural evolution of the lamellar phase. The evaporation rate in the first phase of evaporation up to 60 min is roughly six times faster than that in the second phase. A plausible mechanism is proposed to explain this behaviour. The intrusion of water molecules into layers sandwiched between polar head groups forms an additional 7 Å thick layer of water molecules, leading to an increase in the distance between the head groups. The evaporation of the water molecules in the first phase up to 60 min causes a reduction in the lamellar thickness of ∼3 Å. Subsequent evaporation of water molecules in the second phase is quite slow owing to the higher binding energy of these water molecules and the low permeability caused by the reduced lamellar thickness after the first phase of evaporation. The swelling behaviour of the lamellar structure under ambient conditions is found to be reversible and the powder-phase structure is observed after a few days of evaporation of the gel phase.

Effect of nanoscale confinement on the formation of Ag nanoparticles in porous matrix of nanostructured silica micro-granules has been investigated. One step rapid drying of tiny aerosol droplets has been employed for incorporation of metal precursor in the porous micro-granules. The formation of nanoparticles in the confined geometry of interstitial granular pores has been revealed by small-angle scattering and field-emission scanning electron microscopy. It has been observed that nanometric confinement accelerates the chemical reduction of precursor as compared to that in a bulk solution and the formation yield gets further enhanced by irradiation of X-ray. The growth kinetics of nanoparticles has been probed by time-resolved scattering experiments. It is revealed that X-ray-induced dissociation of bound water in the granular interstices produces hydrated electrons favouring the reduction reaction.

Hypothesis Spray drying is a facile technique to transform colloidal dispersion into micro-granules of controlled size, shape, and morphology. There is significant interest to understand the structural integrity, different morphology of the granules obtained post spray drying which find potential application in many technological fields. The shape of the constituent particles in the colloidal dispersion that is spray dried is expected to influence the micro-structural features of the micro-granules. Experiments We investigate the formation of micro-granules consisting of nano-ellipsoids through controlled spray drying. The morphological features and the packing of ellipsoids in the granules are quantitatively analyzed by using small angle neutron scattering, small angle X-ray scattering and high-resolution field emission scanning electron microscopy. The time evolution of the micro-structure and the structural integrity of the granules are investigated by re-dispersing the powder granules in water. Findings The morphology of the granules are found to be strongly correlated with the aspect ratio of the ellipsoid. While the drying of droplets containing lower aspect ratio ellipsoids give rise to mostly spherical granules, in stark contrast, for higher aspect ratio ellipsoids, micro-granules of different morphologies are formed including doughnut shaped granules. A plausible mechanism explaining such an aspect ratio dependent shape transformation is proposed.

Objective: The aim of the study was to investigate the nephroprotective & hepatoprotective activity of methanolic extract of Clitoria ternatea in Cisplatin & CCl4 induced in rats Methods: Methanolic extract of aerial part of Clitoria ternatea plant was studied for its Nephroprotective & Hepatoprotective activity in animal experiment models. Nephrotoxicity was induced by Cystone 16 mg/kg b.w . Standard drug was taken Silymarin .Test drug were given methanolic extract Clitoria ternatea 500 mg/kg , 1000 mg/kg . Hepatoxicity was induced by CCl4 .Standard drug was taken cisplatin 100 mg/kg . Test drugs were given extract of Clitoria ternatea 500 mg/kg & 1000 mg/kg as per b.w Results : In Hepatoprotective activity positive control group was provided with CCl4 and increased SGPT , SGOT , ALP level compare to negative control group whereas Test(2) group was provided with methanolic extract of Clitoria ternatea 1000 mg/kg decreased SGPT , SGOT , ALP level compare to standard group. In nephroprotective activity positive control group was provided with CCl4 increased Urea and creatinine level where as Test(2) group are provided with methanolic extract of Clitoria ternatea 1000 mg/kg decreased urea and creatinine level Conclusion: On evaluating biochemical parameters it was found that methanolic extract of Clitoria ternatea 1000 mg/kg showed hepatoprotective and nephroprotective activity in rats. Keywords: SGPT, SGOT, ALP, Nephroprotective, Hepatoprotective

As we know inflammatory bowel disease is an emergent plight in rural and developing countries. In USA 10 million of peoples are suffering from IBD.IBD encompasses two pivotal kinds of pathological condition Ulcerative colitis (UC) and Crohn’s disease (CD). Epidemiologically has a greater prevalence in the global prospective. So we decided to zero in on IBD in our work ahead. So a thorough search of available literature IBD is associated with plethora of comorbid disorders which includes gastrointestinal disorders arising from cholelithiasis, cutaneous disease like psoriasis, metabolic disorders like diabetes mellitus. Keywords: IBD: inflammatory bowel disease, CD: Crohn’s disease, UC: Ulcerative colitis

Ulcerative colitis (UC) is a chronic ulceroinflammatory condition primarily confined with in colonic mucosa with variable distortion of the colonic architecture. It is associated with microbial overgrowth such as E.coli , S. typhi .However Chloroquine acts on these microbes . In our present study the anticolitic effects of Chloroquine in treatment with the DSS induced model for UC in mice were examined. Male mice of age 7 weeks are chosen .They are assigned into different groups .Negative control groups treated with normal saline solution ,positive control group treated with DSS5%, standard group treated with Balsalazide 4mg/kg & DSS 5% , Test(1) group treated with Chloroquine 6mg/kg, Test(2) group treated with Chloroquine 8mg/kg, Test(3) group treated with Chloroquine 10 mg/kg then we performed different parameters such as DAI, Oxidative damage assessment, MPO Assessment and Histopathological evaluation. The results have showed that Chloroquine has significant activity against DSS(5%) induced colitis when compared to the experimental control, with near normalization of colon architecture. Tissue oxidative stress was reduced with significant improvement in tissue levels of MDA, GSH, SOD and CAT .Furthermore,significant improvement in levels of myeloperoxidase (MPO) was observed. It is concluded that Chloroquine(10mg/kg) has got potent activity against DSS(5%) induced ulcerative colitis(UC) due to its anti inflammatory antioxidant properties.

In this work, spinodal decomposition (SD) in Fe-35 at.% Cr alloy is quantified by correlatively combining two complimentary techniques namely, Atom Probe Tomography (APT) and Small Angle Neutron Scattering (SANS). In order to overcome the uncertainty often encountered in quantification of the characteristic SD parameters (wavelength λSD , amplitude A and volume fraction of Cr-rich α/ -phase Φ), we adopt the following: (i) utilize the unique specific attribute of a technique suitable for evaluating any particular SD parameter; (ii) incorporate such reliably extracted parameter as input for evaluating other parameters wherever applicable. This novel correlative approach builds on each other’s strength and provides improved accuracy. λSD is determined independently from APT and SANS analyses. For evaluation of A and Φ, APT analysis utilizes the value of λSD determined from SANS, whereas the phase compositions evaluated by APT are utilized in SANS analysis. With progressive phase separation, α/α/ compositional difference increases continually (from 19.8% after 10 h to 48.2% after 500 h) along with concomitant contraction of the interface (from 1.92 nm to 1.55 nm), underscoring the distinctive characteristics of SD process. Signature of rarely observed early stage of phase separation in the form of a dense population (9.78x1024 /m3 ) of extremely small (0.67 nm radius) Cr-rich nanoclusters is registered after aging only for 1 h. In addition, temporal evolution of λSD clearly distinguishes early stage of SD (time exponent of 0.15) from the coarsening stage (time exponent of 0.29, 120 h onwards).

Evaporative assembly of colloids in tiny contact free droplet is a facile and one step process to realize nanostructured microgranules. In such a process, with relatively fast drying rate a random jamming of the nanoparticles are expected. Here we have shown that even in such a rapid random jamming process, a nice local hexagonal ordering can exist. Although the local volume fraction of the nanoparticles in the granules is not affected in a statistically sense, the intermediate range ordering gets influenced depending on the rapidness of the assembly process.

Small-angle X-ray scattering study has been carried out on PVA-Ag nanocomposite, a potential candidate for anti-bacterial application, with varying NPs loading in the range of 0-4wt%. The silver nanoparticles were grown inside the polymer matrix using reduction reaction. The existence of two populations of Ag nanoparticles with typical size range of 1.5-2.5 nm and 9.5-25.0 nm is revealed by SAXS. At higher concentration, the coarsening of silver nanoparticle causes increase in its average size. Interestingly, the smaller nanoparticles are present at all concentrations. This indicates that some population of nanoparticles is capped by polymer and hence its growth process is hindered by adsorbed polymer. A comparative study of PVA-Ag nanocomposites, achieved by in-situ and ex-situ incorporation of Ag nanoparticles in the polymer matrix, indicates that ratio of number densities of smaller and larger nanoparticles is less in ex-situ case that is attributed to the sluggish growth rate of Ag nanoparticles in polymer host due slower diffusion and capping of the nanoparticles.

Microemulsion-templated dendritic fibrous nanosilica (DFNS) has attracted considerable attention owing to their unique accessible pore structure and high-surface-area but their complex structural hierarchy is still intriguing. In this work, a correlative quantification of the hierarchical structure of such nanospheres has been presented based upon three complementary techniques; small-angle scattering, gas sorption, and electron microscopy. Analysis of scattering data over a wide range of wave-vector transfer using polydisperse Teubner Strey model reveals three distinct levels of correlated bicontinuous morphology and the pore-size distribution from N2 gas sorption resembles well with the results obtained from scattering analysis. The formation mechanism of such hierarchical pore morphology in these nanospheres is elucidated and it is observed that a relative variation in periodicity, sheet thickness, and their correlation significantly affects the specific surface area and pore structure, which is strongly influenced by hydrolysis rate and reaction time.

In this work, spinodal decomposition (SD) in Fe-35 at.% Cr alloy is quantified by correlatively combining two complimentary techniques namely, Atom Probe Tomography (APT) and Small Angle Neutron Scattering (SANS). In order to overcome the uncertainty often encountered in quantification of the characteristic SD parameters (wavelength λSD, amplitude A and volume fraction of Cr-rich α/-phase Φ ), we adopt the following: (i) utilize the unique specific attribute of a technique suitable for evaluating any particular SD parameter; (ii) incorporate such reliably extracted parameter as input for evaluating other parameters wherever applicable. This novel correlative approach builds on each other's strength and provides improved accuracy. λSD is determined independently from APT and SANS analyses. For evaluation of A and Φ , APT analysis utilizes the value of λSD determined from SANS, whereas the phase compositions evaluated by APT are utilized in SANS analysis. With progressive phase separation, α/α/ compositional difference increases continually (from 19.8% after 10 h to 48.2% after 500 h) along with concomitant contraction of the interface (from 1.92 nm to 1.55 nm), underscoring the distinctive characteristics of SD process. Signature of rarely observed early stage of phase separation in the form of a dense population (9.78 × 1024/m3) of extremely small (0.67 nm radius) Cr-rich nanoclusters is registered after aging only for 1 h. In addition, temporal evolution of λSD clearly distinguishes early stage of SD (time exponent of 0.15) from the coarsening stage (time exponent of 0.29, 120 h onwards).

Using real time small-angle X-ray scattering, we ellucidate a hitherto unobserved non-monotonic evolution of inter-particle correlation while colloidal particles assemble across pore boundary in a confined medium under influence of solvent evaporation. Time variation of local volume fraction of the particles passes through distinct modulation prior to reaching equilibrium. It has been demonstrated that the amplitude of oscillation depends strongly on size of the assembling particles. We comprehend such non-linear temporal evolution of particle correlation through density functional theory and molecular dynamics simulation.

The nucleation and growth of silica colloids has been studied using real time small-angle X-ray scattering measurements. The ammonium fluorosilicate was used as precursor and both weak (NH3) and strong base (NaOH) has been used as reducing agent for the precursor. It is observed that nucleation, growth and aggregation phenomenon occur simultaneously. The kinetics of the nucleation and growth of silica colloids depends on the strength of the reducing agent as well on its concentration. The kinetics is slow for NH3 but is very fast for higher concentration of NaOH.The nucleation and growth of silica colloids has been studied using real time small-angle X-ray scattering measurements. The ammonium fluorosilicate was used as precursor and both weak (NH3) and strong base (NaOH) has been used as reducing agent for the precursor. It is observed that nucleation, growth and aggregation phenomenon occur simultaneously. The kinetics of the nucleation and growth of silica colloids depends on the strength of the reducing agent as well on its concentration. The kinetics is slow for NH3 but is very fast for higher concentration of NaOH.

We have synthesized nano-structured silica-Escherichia coli composite micro-granules by spray drying of mixed suspension of silica and E. coli through evaporation-induced assembly. Synthesized micro-granules were subjected to calcination in order to form shape-matched macro-pores by removing the bacterial cells. The optimization of calcination temperature is crucial because calcination process leads to two contrasting effects, namely, (i) removal of E. coli from the granules and (ii) alteration of mesoscopic structure in the silica network. We have used small-angle neutron scattering and thermo-gravimetric analysis to determine the optimum temperature for calcination of these granules. It was found that calcination in the temperature range of 200°C to 400°C removes the cells without significant alteration of the nano-structured silica network. However, beyond 500°C, calcination results significant coalescence between the silica particles. Calcination at 600°C eventually collapses the meso-pore network of silica interstices.

Nano-structured composite micro-granules are promising candidates for many technological and medical applications. Understanding the evolution of the mesoscopic structure of these granules, under external thermo-dynamic perturbation, is crucial to assure their use in desired applications. Silica-surfactant micro-granules, primarily of doughnut shape, have been synthesized using one step evaporation-induced assembly through spray drying of mixed dilute colloidal dispersions of silica and sodium dodecyl sulfate (SDS). Composite hollow micro-granules, consisting of densely correlated SDS molecules and silica nano-particles, are obtained because of rapid assembly during spray drying. The trapped water, retained in the spray dried granules, ensures the structural correlation among the SDS molecules in the spray dried granules. While the free water left the granules around 100 °C as expected, the trapped-water in the nano-pores remained even up to 175 °C. Expulsion of the trapped water results in immediate collapse of the correlated surfactant molecules and in turn leads to the rapid restructuring of the silica nano-particles within the granules. In situ X-ray scattering, differential scanning calorimetry and thermo-gravimetric analysis have been utilized to probe the real time thermal evolution of the mesoscopic structure of the synthesized composite granules.