Correlation Of Physicochemical Properties Research Articles

Low-calorie d-allulose as a sucrose alternative modulates the physicochemical properties and volatile profile of sponge cake.

d-Allulose, a C-3 epimer of d-fructose, is a rare sugar with ∼70% of the sweetness of sucrose but a caloric content of only 0.4kcal/g. Due to its low-calorie nature, d-allulose has garnered increasing interest in the food industry. This study was the first attempt to explore the effect of d-allulose as a sucrose replacer on the properties of sponge cake, a widely consumed high-sugar product. Substituting sucrose with d-allulose generated negligible impact on the batter system, while pronounced differences in physicochemical properties of cakes were detected, including specific volume, texture, microstructure, color, and antioxidant activity. In addition, sponge cake containing d-allulose displayed a distinctive aroma volatile profile, with more furans and pyrazines generation. Furthermore, correlations of physicochemical properties across all formulations were depicted, and the potential mechanism behind the property alterations modulated by d-allulose was revealed from the perspectives of starch gelatinization and browning reactions. Overall, this study provides insights into the application potential of d-allulose as a sucrose substitute in bakery product. PRACTICAL APPLICATION: This study elucidates the effect of d-allulose as a low-calorie sugar substitute on sponge cakes. This finding is valuable for the food industry, providing insights into a healthier alternative to traditional sugar in baked goods.

The correlation of physicochemical properties and combustion performance of hydrochar with fixed carbon index

Hydrothermal carbonization (HTC) is effective method for improving fuel properties of biomass. Investigating the relationship between the HTC severity and the physicochemical properties of hydrochar is beneficial for the large-scale utilization. The fixed carbon index (FCI) based on the hydrothermal carbonization severity is introduced to predict the physicochemical properties, pelletization and combustion performance of hydrochar. The results showed the relationship between decarbonization, dehydrogenation, deoxygenation and FCI fits exponential function. It was predicted that the hydrochar pellets with FCI = 0.15–0.45 possessed the highest bulk density (>1175 kg/m3), the lowest specific energy consumption (<16.07 kJ/kg) and the strongest radial compressive strength (>10.7Mpa). Moreover, the activation energy of hydrochar combustion in FCI (0.15–0.25) is higher (the maximum is 216 kJ/mol). The study provides based datas for predicting the fuel properties of hydrochar and obtains high quality solid fuel.

Surface area- and mass-based comparison of fine and ultrafine nickel oxide lung toxicity and augmentation of allergic response in an ovalbumin asthma model

Background: The correlation of physico-chemical properties with mechanisms of toxicity has been proposed as an approach to predict the toxic potential of the vast number of emerging nanomaterials. Although relationships have been established between properties and the acute pulmonary inflammation induced by nanomaterials, properties’ effects on other responses, such as exacerbation of respiratory allergy, have been less frequently explored.Methods: In this study, the role of nickel oxide (NiO) physico-chemical properties in the modulation of ovalbumin (OVA) allergy was examined in a murine model. Results: 181 nm fine (NiO-F) and 42 nm ultrafine (NiO-UF) particles were characterized and incorporated into a time course study where measured markers of pulmonary injury and inflammation were associated with NiO particle surface area. In the OVA model, exposure to NiO, irrespective of any metric was associated with elevated circulating total IgE levels. Serum and lung cytokine levels were similar with respect to NiO surface area. The lower surface area was associated with an enhanced Th2 profile, whereas the higher surface area was associated with a Th1-dominant profile. Surface area-normalized groups also exhibited similar alterations in OVA-specific IgE levels and lung neutrophil number. However, lung eosinophil number and allergen challenge-induced alterations in lung function related more to particle size, wherein NiO-F was associated with an increased enhanced pause response and NiO-UF was associated with increased lung eosinophil burden.Conclusions: Collectively, these findings suggest that although NiO surface area correlates best with acute pulmonary injury and inflammation following respiratory exposure, other physico-chemical properties may contribute to the modulation of immune responses in the lung.

The molecular shape and the field similarities as criteria to interpret SAR studies for fragment-based design of platinum(IV) anticancer agents. Correlation of physicochemical properties with cytotoxicity

Molecular shape similarity and field similarity have been used to interpret, in a qualitative way, the structure-activity relationships in a selected series of platinum(IV) complexes with anticancer activity. MM and QM calculations have been used to estimate the electron density, electrostatic potential maps, partial charges, dipolar moments and other parameters to correlate the stereo-electronic properties with the differential biological activity of complexes. Extended Electron Distribution (XED) field similarity has been also evaluated for the free 1,4-diamino carrier ligands, in a fragment-based drug design approach, comparing Connolly solvent excluded surface, hydrophobicity field surface, Van der Waals field surface, nucleophilicity field surface, electrophilicity field surface and the extended electron-distribution maxima field points. A consistency has been found when comparing the stereo-electronic properties of the studied series of platinum(IV) complexes and/or the free ligands evaluated and their in vitro anticancer activity.

Correlation of Physicochemical Properties with the Catalytic Performance of Fe-Doped Titanium Dioxide Powders

A simple method for synthesis of Fe-doped TiO2 nanocrystalline powders, namely by coprecipitation, is described in this study. The influence of the iron content on the structural, morphological, optical and photocatalytic properties is determined. On the basis of XRD analysis, it was observed that anatase crystalline phase of TiO2 was stabilized, and the deformation of the elemental cell and strain increase with increasing of iron content due to the substitution of Ti4+ with Fe3+. The substitution process and the interaction between titanium and iron ions was also confirmed from the shifting of the Raman fundamental vibration from 144 to 149 cm–1. The absorption spectra showed that the optical response of TiO2 was red-shifted and the optical energy band gap decreased in the case of low content of Fe, whereas at high content of iron (in this case 3.11%), the optical response is blue-shifted due to the quantum size effect. The photocatalytic performance of Fe-doped TiO2 materials was correlated with the optical energy band gap. Thus, the best photocatalytic performance was obtained for the sample that contains 1.48% iron because it displays the lowest energy band gap (2.79 eV), so the material can absorb radiation from the visible range, even if this sample presents the lowest surface area. The efficiency of the degradation of Methylene Blue dye, under exposure to low intensity ultraviolet and visible radiations was 39%. Based on the characterization and performance of the Fe-doped TiO2 materials, it was concluded that the optimal iron content for our studies was 1.48%.

Correlation of physicochemical properties and sludge dewaterability under chemical conditioning using inorganic coagulants

This study investigated the effects of chemical conditioning with three representative inorganic coagulants (FeCl3, polyaluminum chloride (PACl) and high performance PACl (HPAC) on sludge dewaterability. We monitored the particle size, kinetic viscosity (KV), fractal dimension (D(F)) and extracellular polymeric substances (EPS) located in different layers of sludge floc (soluble, loosely-bound (LB), tightly-bound (TB)) to understand the correlation of dewaterability and physicochemical properties of sludge under chemical conditioning. The conditioning process included the rapid aggregation of sludge particles induced by charge neutralization and bridging followed by floc densification caused by double electric layer compression. The floc size and D(F) were increased after chemical conditioning, indicating that larger and more compact floc formed. The floc conditioned with FeCl3 was smaller but denser than that of PACl and HPAC. Furthermore, sludge dewaterability correlated well with the change in concentration of soluble EPS, LB-EPS and TB-EPS, but not with KV, D(F), floc size.

In-Air Graft Copolymerization of Ethyl Acrylate onto Natural Cellulosic Polymers

The present work deals with the graft copolymerization of ethyl acrylate (EA) onto lignocellulosic natural fibers of the Himalayan region in air in the presence of potassium persulfate (KPS) as initiator. Raw fibers and the graft copolymers after the completion of copolymerization reaction were subjected to evaluation of different properties. Correlation of physicochemical properties with the graft copolymerization reaction mechanism is discussed. Characterization of the graft copolymers was carried out with scanning electron microscopy, Fourier transform-infrared spectrophotometry, and thermogravimetric analysis.

Correlation of physicochemical properties with absorption and metabolism of some tricyclic drugs.

Octanol and dodecane partition coefficients, surface activity and adsorbability to activated charcoal were determined for six tricyclic psychotropic drugs with N-dimethylalkyl side chains. Surface activity correlated well with the partition coefficients, and all drugs obeyed the Langmuir adsorption isotherm. A correlation between the reciprocal of the death time of gold fish exposed to drugs and partition coefficients was observed. The extent to which the drugs were N-demethylated as measured by formaldehyde formed in rat liver homogenate incubations correlated with their adsorbability to activated charcoal but not with their ability to inhibit aniline-p-hydroxylase, nor was there a linear correspondence between N-DEMETHYLATION AND DRUG LIPOPHILICITY AS INDICATed by partition coefficients or surface activity.

Toxicity assessment of a complex industrial wastewater using aquatic and terrestrial bioassays Daphnia pulex and Lactuca sativa

Aquatic and terrestrial bioassays were used to assess toxicity at several stages in an industrial wastewater treatment plant that processes 400 L/s from a complex influent formed by wastewater from 135 industries. Daphnia pulex and Lactuca sativa were used to assess and compare toxicity between the influent wastewater and effluent wastewater from an activated sludge process, and compare their relationship with physicochemical parameters of Biological Oxygen Demand (BOD); Chemical Oxygen Demand (COD); Total Suspended Solids (TSS); total Nitrogen (N N-total), and ammonia Nitrogen (N N - NH3). Samples from the primary clarifiers (PC), mix liquor stage (ML) and secondary clarifiers (SC) were processed using physicochemical and bioassay test. Toxicity results with Daphnia pulex showed decreased mean values of acute Toxic Units (a.T.U.) between PC (2.1 a.T.U.) and SC (1,25 a.T.U.). Lactuca sativa showed high values of toxicity between PC and SC (3.37 and 3.32 a.T.U. respectively). Some samples exhibited higher toxicity values at the effluent stage (SC) than the influent stage (PC). The highest correlations of physicochemical properties with toxicity were obtained with COD and nitrogen compounds in effluent samples (SC), but not with influent samples (PC).

Shape-selective methylation of 4-methylbiphenyl to 4,4-dimethylbiphenyl over zeolite HZSM-5 modified with metal oxides of MgO, CaO, SrO, BaO, and ZnO

A series of ZSM-5 samples modified with metal oxides MO (M = Mg, Ca, Sr, Ba and Zn) were employed for the alkylation of 4-methylbiphenyl (4-MBP) with methanol to 4,4'-dimethylbiphenyl (4,4'-DMBP) under fixed-bed down-flow conditions. The methylation results showed that the use of basic metal oxides can effectively enhance the selectivity to the target product 4,4'-DMBP. MgO is the most effective modifier among the metal oxides used and it can improve selectivity to 4,4'-DMBP up to 80% as compared to only 13% over the parent zeolite HZSM-5. The modification effectiveness of metal oxides on 4,4'-DMBP selectivity can be arranged in the order MgO > SrO ∼ ZnO ∼ CaO > BaO. The optimization of MgO modification through the content, salt types and loading methods revealed that proper MgO loading (5.6 wt%) can be more effective, and the impregnation method is much better than ion exchange. The correlation of physicochemical properties (TPD, TGA, chemical analysis and chemical adsorption, etc.) of the modified HZSM-5 with the catalytic data showed that the high selectivity over ZSM-5 modified with MgO largely results from the effective suppression of 4,4'-DMBP secondary reactions such as isomerization, dealkylation and alkylation.

The use of saturated vapor pressure at standard temperature in correlations of physicochemical properties

The saturated vapor pressure (p st) at the standard temperature can be a useful descriptor for correlations of physicochemical properties. Regression analysis of the standard heats of vaporization H st of organic compounds, boiling temperatures T b at the standard pressure, and the heats of vaporization at boiling temperature H vb using the logp st and (logp st)2 values as descriptors in combination with solvatochromic descriptors provided the regressions describing these properties for many organic compounds.

Correlation of physicochemical properties and sub-erosional landforms with aggregate stability variations in a tropical Ultisol disturbed by forestry operations

The stability of soil aggregates against water erosion is a largely unstudied factor in research on the spatially-distributed impacts of tropical forestry. Soil strata with particularly weak aggregates are likely to be the focus for erosional activity whether buried or exposed by either natural processes or forestry activities. Understanding the location and likely cause of such intrinsic instability would, therefore, allow better spatially-distributed parameterisation of erosion models. This study has aimed to identify the range in aggregate stability within a region of Bornean Ultisol disturbed by forestry operations, and to identify the bulk soil properties associated with such stability variations. The sites sampled were subject to a range of denudational processes including piping, rilling and landslide-triggered erosion. Soil profiles with rates of erosion in excess of 10 mm a −1 were shown to have less aggregate stability (as characterised by the rainfall simulation survival index (RSSI)) than those with no visible signs of erosion. Further, large differences in aggregate stability between soil horizons of the same profile were observed and seen to be statistically correlated with the bulk soil properties of organic carbon and clay content (i.e. stabilising agents) and the dispersing agent of exchangeable sodium percentage (ESP) at sites undergoing erosion. Organic carbon appeared to be the most important governing factor, accounting for 56% of the variance in the aggregate stability. The presence of strongly and weakly expanding 2 : 1 clays within the soils may have been an additional de-stabilising factor. Reduced porosity was also observed at eroding sites with weak soil aggregates. The properties of EC 25 and sodium adsorption ratio (SAR) were not correlated with the RSSI or the presence of soil erosion. Identification of the role of organic carbon, clay and ESP in the stability of these tropical forest aggregates is important in focusing future, more intensive research on the spatial parameterisation of models to simulate forestry impacts on erosion.

A biotechnological method provides access to aggregation competent monomeric Alzheimer's 1-42 residue amyloid peptide.

Senile plaques, a neuropathological hallmark of Alzheimer's disease, consist primarily of insoluble aggregates of beta-amyloid peptide (A beta). A 42-residue peptide (A beta 1-42) appears to be the predominant form. In contrast to A beta 1-40, A beta 1-42 is characterized by its extreme tendency to aggregate into fibers or precipitate. A tailored biotechnological method prevents aggregation of A beta 1-42 monomers during its production. The method is based on a protein tail fused to the amino terminus of A beta. This tail leads to a high expression in E. coli, and a histidine affinity tag facilitates purification. Selective cleavage of the fusion tail is performed with cyanogen bromide by immobilizing the fusion protein on a reversed phase chromatography column. Cleavage then occurs only at the methionine positioned at the designed site but not at the methionine contained in the membrane anchor sequence of A beta. Furthermore, immobilization prevents aggregation of cleaved A beta. Elution from the HPLC column and all succeeding purification steps are optimized to preserve A beta 1-42 as a monomer. Solutions of monomeric A beta 1-42 spontaneously aggregate into fibers within hours. This permits the investigation of the transition of monomers into fibers and the correlation of physico-chemical properties with biological activities. Mutations of A beta 1-42 at position 35 influence the aggregation properties. Wild-type A beta 1-42 with methionine at position 35 has similar properties as A beta with a methionine sulfoxide residue. The fiber formation tendency, however, is reduced when position 35 is occupied by a glutamine, serine, leucine, or a glutamic acid residue.

78. Some physico-chemical properties of acridine antimalarials, with reference to their biological action. Part III. The correlation of physico-chemical properties with biological action

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