We study a class of quasilinear elliptic equations with boundary blow-up. Based on super and sub-solution arguments and certain
comparison principle, we prove the existence of non-negative solutions of (1.1). Moreover, we show the existence of maximal
and minimal non-negative solutions of (1.1).
We prove that the conjugate convolution operators can be used to calculate jumps for functions. Our results generalize the theorems established by He and Shi. Furthermore, by using Lukács and Móricz's idea, we solve an open question posed by Shi and Hu.
A three-dimensional leaching model was developed to describe the leaching of radionuclide from a cement-based concrete solid. The film mass transfer and interparticle diffusion were considered simultaneously. On the basis of the derived model the long-term behavior of radium-226 leaching from the waste solid has been quantitatively investigated.
The stems of Uncaria rhynchophylla (Miq.) ex Havil have a long history of use in traditional Chinese medicine to treat diseases and improve health. There is evident evidence that alkaloids constituents are mainly responsible for the beneficial effects of this plant medicine. The amounts of the major bioactive alkaloids in this plant vary widely with species, habitat, and as such, and establishment of a high-performance liquid chromatography (HPLC) fingerprint for quality control of this herbal medicine is of particular importance. The most alkaloids are used for medicine treatment and research. On the basis of the chromatographic data, a consistent HPLC fingerprint pattern containing 15 common peaks was obtained. Among these common peaks, four were identified as rhynchophylline, isorhynchophylline, corynoxeine, and isocorynoxeine. On the basis of this HPLC fingerprint and principal-components analysis, the quality of fifteen samples from different producing areas of China was objectively assessed. To summarize, the data described in this study offer valuable information for quality control and proper use of U. rhynchophylla (Miq.) ex Havil.
N,N,N,N-tetrabutylsuccinylamide (TBSA) was synthesized, characterised and used for the extraction of U(VI) and Th(IV) from nitric acid solutions into n-dodecane. Extraction distribution coefficients of U(VI) and Th(IV) as a function of aqueous nitric acid concentration, extractant concentration and temperature have been measured and found that n-dodecane as diluent was superior to 50% 1,2,4-trimethyl benzene (TMB) and 50% kerosene, (OK) system for extraction of U(VI) and Th(IV). The compositions of extracted species, equilibrium constants and enthalpies of extraction reactions have also been calculated. The formation of the 121 complex of uranyl(II) ion or the 141 complex of thorium(IV) ion, nitrate ion and TBSA and extracted species was further confirmed by the IR spectra of saturated extract of U(IV) and Th(IV).
Chinese sources document foreign names with phonetic transcriptions and render them in Chinese characters with close, or at least approximate, sound value. Among the Sogdians who were active at the Chinese court of the 6th century there were two persons named He Zhuruo and An Weiruo respectively. The etymology of both names can now be tentatively identified with Maniach, the name which was recorded in a Byzantine source, being that of a Sogdian envoy to Constantinople. Hence the original written form of Zhuruo and Weiruo can be restored with the spelling Moruo. The reason for these misspellings goes back to the graphic similarity of the concerned characters. Some further emendations of similar kinds are also proposed.
The thermogravimetric analysis (TG) of two series
of tri-block copolymers based on poly(L,L-lactide) (PLLA) and poly(ethyleneglycol) (PEG)
segments, having molar mass of 4000 or 600 g mol–1,
respectively, is reported. The prepared block copolymers presented wide range
of molecular masses (800 to 47500 g mol–1)
and compositions (16 to 80 mass% PEG). The thermal stability increased with
the PLLA and/or PEG segment size and the tri-block copolymers prepared from
PEG 4000 started to decompose at higher temperatures compared to those copolymers
from PEG 600. The copolymers compositions were determined by thermogravimetric
analysis and the results were compared to other traditional quantitative spectroscopic
methods, hydrogen nuclear magnetic resonance spectrometry (1HNMR)
and Fourier transform infrared spectrometry (FTIR). The PEG 4000 copolymer
compositions calculated by TG and by 1HNMR, presented
differences of 1%, demonstrating feasibility of using thermogravimetric analysis
for quantitative purposes.
Authors:W. Dan, Y. Di, Y. Kong, Q. Wang, W. Yang and D. Wang
The complex (C11H18NO)2CuCl4(s) was synthesized. Chemical analysis, elemental analysis, and X-ray crystallography were used to characterize the structure
and composition of the complex. Low-temperature heat-capacities of the compound were measured by an adiabatic calorimeter
in the temperature range from 77 to 400 K. A phase transition of the compound took place in the region of 297–368 K. Experimental
molar heat-capacities were fitted to two polynomial equations of heat-capacities as a function of the reduced temperature
by least square method. The peak temperature, molar enthalpy, and entropy of phase transition of the compound were calculated
to be Ttrs = 354.214 ± 0.298 K, ΔtrsHm = 76.327 ± 0.328 kJ mol−1, and ΔtrsSm = 51.340 ± 0.164 J K−1 mol−1.
Authors:J.W. Zhang, J.H. Wang, G.H. Wang, C.C. Wang and R.Q. Huang
Phenolic extract from banana peel was extracted with 95% ethanol and characterized by LC-TOF-MS/MS. Epicatechin, rutin, 3,4-dihydroxybenzaldehyde, 3,4-dihydroxybenzoic acid, myricetin, ferulic acid, chlorogenic acid, and gallic acid were detected in the extract. Cholate test was performed for the initial examination of the hypolipidemic effect of the dietary fibres. The dietary fibres prepared by sequential treatment with sulphuric acid then sodium hydroxide (SST) and sodium hydroxide treatment (SHT) had high water-holding capacities (7.48 and 6.91 g g−1) and swelling capacities (4.8 and 4.3 ml g−1). The dietary fibres prepared by sequential treatment with trypsin then sulphuric acid (TST) and sulphuric acid treatment (SAT) had high oil-holding capacities (5.52 and 5.10 g g−1) and enhanced capacities for sodium cholate adsorption. Results indicated the potentials of banana peel as functional ingredient in food applications.
Authors:W.Y. Gao, Y.W. Wang, L.M. Dong and Z.W. Yu1
A microcalorimeter (Setaram c-80) was used
to study the thermokinetics of the hydration process of calcium phosphate
cement (CPC), a biocompatible biomaterial used in bone repair. The hydration
enthalpy was determined to be 35.8 J g–1
at 37.0°C when up to 80 mg CPC was dissolved in 2 mL of citric buffer.
In the present study, parameters related to time constants of the calorimeter
were obtained by fitting the recorded thermal curves with the function θ=Ae–?t(1– e–?2t).
The real thermogenetic curves were then retrieved with Tian function and the
transformation rate of the hydration process of CPC was found to follow the
The microstructures of the hydrated CPC were examined by scanning electron
microscopy. The nano-scale flake microstructures are due to crystallization
of calcium phosphate and they could contribute to the good biocompatibility
and high bioactivity.