Hydrophilic lecithins protect milk proteins against heat-induced aggregation

In the present study, the heat-induced interaction between whey proteins and casein micelles was studied. To that end, the particle size distribution of 5.5% (w/w) casein micellar dispersions was determined by photon correlation spectroscopy as a function of both the whey protein concentration and heating time at 80 °C. The results clearly indicated that heat-induced aggregation of the casein micelles only occurred in the presence of whey proteins.

In an effort to overcome the heat-induced interactions between whey proteins and casein micelles, the influence of different soybean lecithins was investigated. Comparing native to hydrolysed, as well as hydroxylated soybean lecithin, it was observed that the heat-stabilising effect of the lecithins was directly related to their hydrophilicity: whereas native soybean lecithin had hardly any beneficial effect, highly hydrolysed as well as hydroxylated soybean lecithin largely prevented heat-induced casein micelle aggregation in the presence of whey proteins.

From experimental observations on the heat-induced decrease of whey protein solubility both in the absence and presence of hydrolysed lecithin, it was deduced that the latter may stabilise the exposed hydrophobic surface sites of heat-denatured whey proteins. Dynamic surface tension measurements indicated that the heat-stabilising properties of lecithins were mainly determined by their critical aggregation concentration.     

Highly Porous Hydroxyapatite/Graphene Oxide/Chitosan Beads as an Efficient Adsorbent for Dyes and Heavy Metal Ions Removal

Dye and heavy metal contaminants are mainly aquatic pollutants. Although many materials and methods have been developed to remove these pollutants from water, effective and cheap materials and methods are still challenging. In this study, highly porous hydroxyapatite/graphene oxide/chitosan beads (HGC) were prepared by a facile one-step method and investigated as efficient adsorbents. The prepared beads showed a high porosity and low bulk density. SEM images indicated that the hydroxyapatite (HA) nanoparticles and graphene oxide (GO) nanosheets were well dispersed on the CTS matrix. FT-IR spectra confirmed good incorporation of the three components. The adsorption behavior of the obtained beads to methylene blue (MB) and copper ions was investigated, including the effect of the contact time, pH medium, dye/metal ion initial concentration, and recycle ability. The HGC beads showed rapid adsorption, high capacity, and easy separation and reused due to the porous characteristics of GO sheets and HA nanoparticles as well as the rich negative charges of the chitosan (CTS) matrix. The maximum sorption capacities of the HGC beads were 99.00 and 256.41 mg g⁻¹ for MB and copper ions removal, respectively.     

The insertion of sulfur and selenium into the 1,2-dihydrophosphete ring

Sulfur and selenium react with a 1,2-dihydrophosphete P-W(CO)₅ complex at ca. 120°C to give the corresponding 2,5-dihydro-1,2-thiaphosphole and 2,5-dihydro-1,2-selenaphosphole complexes, respectively. These products result from an insertion of S or Se into the P C sp³ bond of the four-membered ring.     

Maximal generating degrees of integral closures of powers of monomial ideals

Journal of Algebraic Combinatorics - We give effective lower and upper bounds on the maximal generating degree $$d(\overline{I^n})$$ and the Castelnuovo–Mumford regularity...     

Preparation of poly(vinyl pivalate) microspheres by dispersion polymerization in an ionic liquid and saponification for the preparation of poly(vinyl alcohol) with high syndiotacticity

We report here a successful free-radical dispersion polymerization of vinyl pivalate (VPi) in an ionic liquid, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([bmim][TFSI]) using poly(vinyl pyrrolidone) (PVP) as a stabilizer. Morphological analysis by FE-SEM revealed that poly(vinyl pivalate) (PVPi) obtained from dispersion polymerizations were in the form of spherical particles. Micron-sized, PVPi particles with a number-average molecular weight (M_n) of 166,400 g/mol could be obtained using 5% stabilizer (w/w to monomer) at 65 °C for 20 h. The effects of varying concentration of stabilizer, initiator and monomer upon polymer yield, molecular weight, and morphology of PVPi were also investigated. Analogous polymerizations in dimethyl sulfoxide (DMSO) and bulk served as references. In addition, the preparation of poly(vinyl alcohol) (PVA) by saponification of the resultant PVPi was described.     

Bose–Einstein condensation in binary mixture of Bose gases

The Bose–Einstein condensation (BEC) in a binary mixture of Bose gases is studied by means of the Cornwall–Jackiw–Tomboulis (CJT) effective action approach. The equations of state (EoS) and various scenarios of phase transitions of the system are considered in detail, in particular, the numerical computations are carried out for symmetry restoration (SR), symmetry nonrestoration (SNR) and inverse symmetry breaking (ISB) for getting an insight into their physical nature. It is shown that due to the cross interaction between distinct components of mixture there occur two interesting phenomena: the high temperature BEC and the inverse BEC, which could be tested in experiments.     

Determination temperature of a backward heat equation with time-dependent coefficients

We introduce the truncation method for solving a backward heat conduction problem with time-dependent coefficients. For this method, we give the stability analysis with new error estimates. Meanwhile, we investigate the roles of regularization parameters in these two methods. These estimates prove that our method is effective.     

Weighted monotonicity inequalities for traces on operator algebras

We study inequalities of the form $$ \tau (w(A)^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} f(A)w(A)^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} ) \leqslant \tau (w(A)^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} f(B)w(A)^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} ),A \leqslant B $$ where τ is a trace on a von Neumann algebra or a C*-algebra, A and B are self-adjoint elements of the algebra in question, f and w are real-valued functions, and the “weight” function w is nonnegative.     

On the quotient between length and multiplicity

In this paper, the exchange ring R with the (general) ?₀-comparability is studied. A ring R is said to satisfy the general ?₀-comparability, if for any idempotent elements f, g ∈ R, there exist a positive integer n and a central idempotent element e ∈ R such that f Re ?_⊕ n[gRe] and gR(1 ? e) ?_⊕ n[f R(1 ? e)]. It is proved that the (general) ?₀-comparability for exchange rings is preserved under taking factor rings, matrix rings and corners. The ?₀-comparability condition for exchange rings R is characterized by the order structure of several partially ordered sets of ideals of R. For any exchange ring R with general ?₀-comparability and any proper ideal I of R not contained in J(R), it is proved that if I contains no nonzero central idempotents of R, then: 1) There exists an infinite set of nonzero idempotent elements {f _i ∣ i = 1,2, …} in I such that f ₁ R ?_⊕ f ₂ R ?_⊕ …, and n(f _n R) ?_⊕ R _R for all n ≥ 1; 2) For any m ≥ 1, there exist nonzero orthogonal idempotents e ₁, e ₂ …, e _m in I such that e ₁ R ⊕ e ₂ R ⊕ … ⊕ e _m R ?_⊕ I _R and e _i R ? e _j R for all i, j. For any exchange ring R with primitive factor rings artinian, if R satisfies the general ?₀-comparability, then in every ideal I of R not contained in J(R), there is a central idempotent element of R.     

A Ruthenium‐Based Biomimetic Hydrogen Cluster for Efficient Photocatalytic Hydrogen Generation from Formic Acid

A ruthenium‐based biomimetic hydrogen cluster, [Ru₂(CO)₆(μ‐SCH₂CH₂CH₂S)] ( 1 ), has been synthesized and, in the presence of the P ligand tri(o‐tolyl)phosphine, demonstrated efficient photocatalytic hydrogen generation from formic acid decomposition. Turnover frequencies (TOFs) of 5500 h^?1 and turnover numbers (TONs) over 24 700 were obtained with less than 50 ppm of the catalyst, thus representing the highest TOFs for ruthenium complexes as well as the best efficiency for photocatalytic hydrogen production from formic acid. Moreover, 1 showed high stability with no significant degradation of the photocatalyst observed after prolonged photoirradiation at 90 °C.