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Accurate prediction of lithium ion (li-ion) battery capacity is of great significance to battery health status management. In this paper, the different discharge time corresponding to the equal voltage interval is taken as the health factor. Three highly correlated health factors are extracted from the battery discharge curve, and the Back Propagation neural network (BPNN) optimized by a genetic algorithm (GA) is used to estimate the battery capacity accurately and quickly. Firstly, health factors related highly to battery capacity from the battery cycle life test are extracted, and the selected health factors are analyzed using the Spearman correlation coefficient and Pearson correlation coefficient. Secondly, this paper analyzes the prediction effect of different combinations of selected health factors using BPNN optimized by a genetic algorithm. Then, to verify the superiority of the proposed optimization algorithm, different optimization algorithms are used to adjust and optimize the parameters of BPNN automatically, and the experimental data are used for comparative analysis. Finally, the GA-BP is compared with other common battery capacity prediction methods. The results show that the GA-BP neural network prediction model can accurately and effectively predict the capacity of li-ion battery when using selected health factors. [ABSTRACT FROM AUTHOR]

m-Cresol and p-cresol are widely used in medicine and pesticides as important chemical intermediates. They are generally produced as a mixture in industry and are difficult to separate due to the similarities in both chemical structures and physical properties. The adsorption behaviours of m-cresol and p-cresol on zeolites (NaZSM-5 and HZSM-5) with different Si/Al ratios have been compared by static experiments. Selectivity on NaZSM-5(Si/Al = 80) could be greater than 6.0. Adsorption kinetics and isotherms were investigated in detail. The kinetic data was correlated by PFO, PSO, and ID models, the NRMSE of which were 14.03%, 9.41%, and 21.11%, respectively. In the meanwhile, according to the NRMSE of Langmuir (6.01%), Freundlich (57.80%), D-R (1.1%), and Temkin (0.56%) isotherms, adsorption on NaZSM-5(Si/Al = 80) was mainly a monolayer and chemical adsorption process. It was endothermic for m-cresol and exothermic for p-cresol. The Gibbs free energy, entropy, and enthalpy were calculated accordingly. The adsorption of cresol isomers on NaZSM-5(Si/Al = 80) were both spontaneous, and it was exothermic (ΔH = −37.11kJ/mol) for p-cresol while endothermic (ΔH = 52.30kJ/mol) for m-cresol. Additionally, ΔS were respectively −0.05 and 0.20 kJ·mol−1·K−1for p-cresol and m-cresol, which were both close to zero. The adsorption was mainly driven by enthalpy. The result of breakthrough further demonstrated m-cresol and p-cresol could be separated effectively by NaZSM-5(Si/Al = 80). Additionally, the selectivity increased from 7.53 to 14.72 after four cycles regeneration with 9.95% and 53.96% decreases in the adsorption amounts for m-cresol and p-cresol, respectively. In conclusion, NaZSM-5(Si/Al = 80) could be a feasible adsorbent for the separation of m-cresol and p-cresol. [ABSTRACT FROM AUTHOR]

To investigate the effect of visceral obesity on short-term outcomes after laparoscopic appendectomy (LA). a retrospective study on 441 patients who underwent a LA between July 2019 and July 2020. According to the cutoff visceral fat area (VFA) for visceral obesity, the patients were divided into two groups: visceral obesity group (n = 123) and non-visceral obesity group (n = 318). The general information, comorbidities, perioperative monitoring indicators, and postoperative complications of the patients were collected. Compared with the non-visceral obesity group, the proportion of overweight patients (56.10%), preoperative white blood cell count (12.92 (9.99, 15.58)*109mg/dl), postoperative white blood cell count (9.71 ± 3.91*109mg/dl), and hospitalization costs (16,220.93 ± 7038.76¥) in the visceral obesity group were significantly different (all p < 0.05). Additionally, multivariate logistic regression analysis revealed that visceral obesity (2.679, 95%CI: 1.155–5.849, p = 0.027), indwelling drainage tube (7.832, 95%CI: 2.151–27.428, p < 0.001), and perforated appendicitis (3.181, 95%CI: 1.195–7.136, p = 0.025) were identified to be independent risk factors for incision infection after LA. The area under receiver operating characteristic (ROC) curve value for VFA predicting incisional infection after LA was 0.770. Visceral obesity is one of the independent risk factors for incisional infection after LA, and can be used as one of the reference indicators for prognostic assessment of short-term outcomes after LA. [ABSTRACT FROM AUTHOR]

Both early correction of anemia and preserving residual renal function (RRF) are reported to improve patient survival. The aim of this study was to explore the efficacy and safety of Roxadustat for treatment of renal anemia in patients new to peritoneal dialysis (PD) and to assess its impact on RRF. A retrospective analysis was performed on 60 initial peritoneal dialysis (PD) patients with renal anemia. Twenty-eight cases were treated with Roxadustat (Roxadustat group) and 32 with recombinant human erythropoietin (control group). Clinical characteristics, hemoglobin (Hb), C-reactive protein, blood lipids, iron metabolism, dialysis adequacy and RRF of the two groups were evaluated and adverse events were recorded. All patients were followed up for at least 40 weeks. After 40 weeks of treatment, mean Hb levels were significantly higher from baseline values in both groups, the mean Hb change in Roxadustat group was higher than control group (3.46 ± 1.59 g/dL vs. 2.28 ± 2.27 g/dL, p < 0.05). At 40 weeks, 92.9% patients met the target level of Hb in Roxadustat group and 84.4% in control group. Total iron binding was higher and ferritin was lower in Roxadustat group from baseline values and Roxadustat-induced Hb increases were independent of baseline C-reactive protein levels and history of rhuEPO administration. RRF decreased over time in both groups, the mean RRF change was lower in Roxadustat group than control group (1.15 ± 1.66 mL/min/1.73 m2 vs. 2.31 ± 1.46 mL/min/1.73 m2, p < 0.01). Compared with control group, patients in Roxadustat group had higher levels of total iron binding, 24 h urine volume, total weekly Ccr, and lower systolic pressure, ferritin, C-reactive protein, total cholesterol, LDL. No serious adverse reactions occurred in either group. In patients new to PD, Roxadustat effectively and safely improved renal anemia and delay the decline of RRF. [ABSTRACT FROM AUTHOR]

Liquid − liquid equilibrium (LLE) data for the water + 2,3-butanediol (2,3-BD) + solvent (n-hexanol or iso-pentanol) ternary systems were obtained at different temperatures (298.2, 308.2, and 318.2 K) under 101.3 kPa. Distribution coefficients and separation factors were calculated accordingly. Distribution coefficients and separation factors were greater than 0.2 and 2.5, respectively, for both n-hexanol and iso-pentanol, which indicated that they were feasible to extract 2,3-BD from aqueous solution. Meanwhile, the reliability of the experimental LLE data was confirmed by both Othmer − Tobias equation and Hand equation. Lastly, the LLE data were correlated by both thermodynamic nonrandom two-liquid (NRTL) and universal quasi-chemical (UNIQUAC) models, and their binary interaction parameters were correlated from the data. In addition, topological analysis related to the Gibbs minor common tangent test was applied to validate the binary interaction parameters. Supplemental data for this article is available online at here. [ABSTRACT FROM AUTHOR]

AbstractThe solubility of nicotinohydrazide in two binary solvents were determined by a static weight method from 293.15 to 318.15 K. It found that the solubility of nicotinohydrazide was influenced by temperature, solvent polarity, and solvent composition. Meanwhile, the TG-DSC analysis was used to obtain the weight change and thermal effect of nicotinohydrazide. The XRD analysis indicated that the crystal morphology of nicotinohydrazide was coincident in five different solvents. Furthermore, the models including modified Apelblat equation, Van’t Hoff equation, Jouyban-Acree model, and CNIBS/R-K model were used to fit the experimental data. It was concluded that the four models were reliable in fitting the experimental data. Then the dissolution apparent thermodynamic was obtained, which explained well the dissolution of nicotinohydrazide. This study could help optimize and control the industrial crystallization of nicotinohydrazide. [ABSTRACT FROM AUTHOR]

AbstractGlycylglycine (Gly–Gly) is a crucial biochemical reagent widely used in cosmetics, food additives, and medicine. Using the equilibrium method, the solubility data of Gly–Gly in four binary solvents (ethanol/isopropanol/ethanediol/acetone + water) were investigated at temperatures over a range of 288.15–328.15 K under 101.3 kPa, as well as in the binary solvent of acetic acid + water from 293.15 to 333.15 K. The solubility data were correlated by Apelblat-Jouyban Acree, Van’t Hoff-Jouyban Acree, and CNIBS/Redlich-Kister models. Additionally, the radial distribution function was obtained through molecular dynamic simulation. It presented the unusual dissolution behavior of Gly–Gly in acetic acid and water mixture. The apparent thermodynamic properties, including standard enthalpy, Gibbs free energy, and entropy change of dissolution, were obtained accordingly. This article could help the industrial crystallization of Gly–Gly. [ABSTRACT FROM AUTHOR]

We previously developed a four-arm, four-flipper disaster response robot called OCTOPUS to perform complex tasks at severe disaster sites. Its 22 degrees of freedom (DOF) enable advanced mobility and workability, but requires a minimum of two operators to control it. Considering the limitations of the current automated systems and the need to reduce human resources, it is practical to control OCTOPUS through a shared control. This entails a human-automation (HA) control system that independently allocates control authority between a human and automated system so as to simultaneously cover all DOF in what we call 'separative shared control'. To establish an HA control system, control authority allocation (CAA) must be carefully designed. We first performed experiments with a human-human (HH) control system using a VR simulator. We determined four tasks and five CAAs and then selected the optimum CAA by analyzing the results. We then developed an HA control system utilizing the selected CAA that replaces either human operator with a simple automated system. We compared the performance of the HH and HA control systems in the above four tasks using the VR simulator and found that the HA achieved less workload and higher subjective usability than the HH. [ABSTRACT FROM AUTHOR]

This paper introduces a flexible puncture method that can improve the efficiency and safety of robot-assisted central venous catheterization (CVC) surgery systems. Current CVC surgery-assisted manipulators and systems are mainly focused methods for puncture needle insertion into blood vessels. There is no single systematic stratagem for safe high-precision control of the posture of the needle in a blood vessel after needle insertion. However, this type of control stratagem is both necessary and urgently required in surgery to avoid piercing the central vein and to provide a suitable posture for guide wire insertion. Therefore, we propose the remote centre of motion control method to control the needle's posture precisely and safely. Verification experiments were performed in both a simulator and a puncture manipulator. The results indicate that the needle tip trajectory in the simulation is completely accurate and it also agrees well with the theoretical value. The positional and angular errors of the needle tip are smaller than 0.8 mm and 1.8°, respectively, in the real puncture manipulator experiment; these errors are sufficiently small for surgeries. The proposed design is practical and can be used in real puncture manipulators and systems. [ABSTRACT FROM AUTHOR]

The isobaric vapor–liquid equilibrium (VLE) data at 101.3kPa for (1,3-propanediol(PG) + 1,3-butanediol(BD)), (1,3-PG+2,3-BD) and (1,3-BD+2,3-BD) and for the ternary system of (1,3-PG+1,3-BD+2,3-BD) have been measured. The thermodynamic properties of the non-ideal vapor phase have been considered with the EOS equation. The liquid activity coefficients have been calculated with Wilson, NRTL and UNIQUAC equations, and the binary interaction parameters were regressed by these models. The vapor composition of VLE data were calculated by the optimum parameter group and generated a good consistency to experimental values. Based on all the preceding results, a two-column distillation process was designed. [ABSTRACT FROM AUTHOR]

Objective: To investigate the role of lncRNA ANRIL in the modulation of myocardial cell apoptosis in acute myocardial infarction (AMI). Methods: AMI mice model was established, and lncRNA ANRIL, IL-33 and ST2 expressions were detected by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. The apoptosis of myocardial cells was detected by TUNEL assay. RNA pull-down and RNA immunoprecipitation (RIP) assays were used to confirm the interaction between lncRNA ANRIL and USP17. Results: Compared with sham group, lncRNA ANRIL and ST2 expression levels were up-regulated, and the apoptosis of myocardial cells was increased in heart tissues of AMI group. Compared with normoxia group, the apoptosis of mouse myocardial cell HL-1 and primary murine myocardial cells was increased, and lncRNA ANRIL and ST2 expression levels were up-regulated in hypoxia group. We also found up-regulation of IL-33 in AMI group and hypoxia group. Besides, lncRNA ANRIL affected deubiquitinase USP17-mediated degradation of IL-33. Interfering lncRNA ANRIL reduced the apoptosis of myocardial cells through IL-33/ST2 pathway. In vivo experiments found that interfering lncRNA ANRIL relieved myocardial cell apoptosis and improved heart function in AMI mice. Conclusion: LncRNA ANRIL regulated myocardial cell apoptosis through IL-33/ST2 pathway. [ABSTRACT FROM AUTHOR]

The solubility data of N-acetylglucosamine in five pure solvents (water, methanol, ethanol, n-propanol and acetone) and two binary solvents (water + ethanol, water + acetone) were measured by gravimetric method at temperatures from 283.15 to 313.15 K under atmosphere pressure (p = 101 kPa). The solubility data show that the solubility of N-acetylglucosamine in pure solvents increases with the increasing temperature and the solubility in binary solvents is affected by temperature and solvent composition. The solubility data of N-acetylglucosamine in pure solvents were correlated by Van't Hoff model, modified Apelblat model, λh model and the modified Apelblat model has the best performance. Jouyban-Acree model was used to correlate the solubility data of N-acetylglucosamine in binary solvents and the fitting performance was well. The dissolution thermodynamic properties of N-acetylglucosamine in all solvents were also estimated in this work. The experimental data will be helpful for purification process of N-acetylglucosamine in industry. [ABSTRACT FROM AUTHOR]

The solubility data of N-acetyl-L-glutamine in aqueous solution with different proportions of methanol and ethanol were determined with a static analytical method from 293.15 to 318.15 K. The data were then correlated by five models including the modified Apelblat equation, Van't Hoff equation, local composition model (NRTL model), CNIBS/Redlich-Kister model, and Jouyban-Acree model. The results show that Van't Hoff equation agrees well with the experimental data. When the ratio of methanol or ethanol in aqueous solution is in the range of 0.2-0.4, the solubility of N-acetyl-L-glutamine reaches its maximum. Besides, the melting temperature and fusion enthalpy of N-acetyl-L-glutamine were measured by the differential scanning calorimetry (DSC) and no polymorphism was found in the systems studied. The thermodynamic properties including enthalpy, entropy and Gibbs free energy during dissolution were calculated accordingly in this work. [ABSTRACT FROM AUTHOR]

Polyurethane modified with polylactic acid microcapsules were fabricated for controlled release of chlorpyrifos (one of the high usage solid phosphorous insecticides) via interfacial polymerisation with diphenylmethane diisocyanate, polyether triol, 1,4-butanediol and polylactic acid as modifier. The structure, morphology and release properties of synthesised microcapsules were characterised by Fourier transform infra-red spectroscopy, thermogravimetric analyser, scanning electron microscope, particle size analyser and high-performance liquid chromatography. More benign solvents, namely ethyl acetate and n-butyl acetate were used as replacement for toxic solvents commonly used in the preparation of polyurethane microcapsules, namely xylene. The spherical microcapsules prepared in this study were 1–20 μm in diameter. Fourier transform infra-red spectroscopy indicated that polylactic acid had successfully participated in the interfacial polymerisation of polyurethane. Encapsulation efficiency of microcapsules can amount up to 71.0% w/w with a loading efficiency of 26.2% w/w. The microcapsules exhibited a sustained release period above 60 days. Combining polylactic acid into the soft segment of polyurethane proves to effectively accelerate the release rate. [ABSTRACT FROM AUTHOR]

A study on separation of system (1,2-ethanediol (1,2-EG) + 1,3-butanediol (1,3-BD) + 1,3-propanediol (1,3-PG)) was conducted in the article. Vapor-liquid equilibria (VLE) behaviors of systems (1,2-EG + 1,3-BD), (1,2-EG +1,3-PG), (1,2-EG + 1,3-BD + 1,3-PG) were studied at 101.3 kPa. A two-column (column C1 and column C2) sequence distillation process at normal pressure was designed and optimized to separate the ternary mixture. The results have shown Wilson model is the most appropriate one to describe the ternary system; product amounts of 1,2-EG, 1,3-BD, and 1,3-PG can be up to 0.970, 0.945, and 0.980, respectively, under optimized conditions. [ABSTRACT FROM AUTHOR]

Thermodynamic behaviors of ternary system (1,2-propanediol (1,2-PG) + 1,3-butanediol (1,3-BD) + 1,4-butanediol (1,4-BD)) were studied in this paper. Vapor-liquid equilibria (VLE) data of systems (1,2-PG + 1,3-BD), (1,2-PG + 1,4-BD), (1,3-BD + 1,4-BD), and (1,2-PG + 1,3-BD + 1,4-BD) were measured at 101.3 kPa. The binary interactive parameters were obtained by regressed the binary VLE data with different models. The results have shown that the Wilson model, the NRTL model and the UNIQUAC model are suitable to describe the ternary system, but the UNIFAC model is not appropriate; the residue curve map of the ternary system was obtained on the basis of the binary interactive parameters. Finally, the design and optimization of the two-column sequence distillation process were completed for separation of the ternary system. Under the optimized conditions, product amounts of 1,2-PG, 1,3-BD, and 1,4-BD can be up to 0.98, 0.90, and 0.98, respectively, after separation. [ABSTRACT FROM AUTHOR]

A polymer–salt aqueous two-phase system based on polyethylene glycol and sulfates was applied to explore the partition behavior of spiramycin. Binodal curves were measured by the turbidimetric titration method. The influence of temperature, salt concentration, and pH on the distribution behavior was investigated in detail by determining the partition coefficient and extraction efficiency. As pH and salt concentration increase, the partition coefficients increase accordingly. It was found that pH displays a significant influence on the partition behavior. The partition coefficient and extraction efficiency can reach 42.46 and 97.8%, respectively, at pH 9.0 and 15.80% (w/w) salt concentration. [ABSTRACT FROM AUTHOR]

A new oleanolic-type triterpene glycoside, (3β,21β)-21-[(β-d-glucopyranosyl-(1→2)-β-d-glucopyranosyl)oxy]-3-hydroxyolean-12-en-28-oic acid (1), together with five analogues, oleanazuroside 1 (2), oleanazuroside 2 (3), 24-hydroxytormentic acid ester glucoside (4), 24-epi-pinfaensin (5), and oleanolic acid 3-O-α-l-arabinoside (6) were isolated from the n-butyl alcohol extract of Anchusa italica. Their structures were determined spectroscopically and compared with previously reported spectral data. Compounds 3–4 and 6 were evaluated for their cytotoxic activities against five human cancer cell lines, but only compound 6 showed moderate cytotoxicity. [ABSTRACT FROM AUTHOR]

Thermodynamic properties of sodium gluconate (SG) aqueous solution have been measured over the 303.15–343.15 K temperature range including solubility, density, and viscosity. For proper crystallization of SG, the kinetics of evaporative crystallization with spontaneous nucleation was subsequently investigated in a semi-batch mode. The crystals present a size-dependent growth rate, and the number particle size distribution (PSD) data were well fitted with the MJ2 model. The effects of supersaturation, suspension density, and agitation intensity were carefully analyzed to contribute to a better understanding for the control of crystal size of SG. [ABSTRACT FROM PUBLISHER]

The crystal transformation of ammonium polyphosphate crystalline form V (APPv) was studied. The effects of heating time and water content in the reactor were explored. The results showed that APPv underwent complete conversion to crystalline form II (APPii) when heated at 200°C. The pure and water-insoluble APPii was obtained under the alternate wet ammonia and dry ammonia atmosphere. Then, the thermal behavior of APPv and APPii was investigated. The TG analysis showed APPv had high thermal stability over the range of 300°C to 580°C, which was possibly due to its highly cross-linked structures. [ABSTRACT FROM AUTHOR]

Etomidate is a unique drug used for induction of general anesthesia and sedation, and is usually used through intravenous injection clinically. Before targeting to the receptor, etomidate binds proteins in blood when it comes into veins. Thus to study the interaction of etomidate and serum albumin would be of great toxicological and pharmacological importance. In this study, the interaction between etomidate and human serum albumin (HSA) was studied using fluorescence spectroscopy, UV–vis absorption spectroscopy, Fourier transform infrared spectroscopy (FT-IR), circular dichroism (CD) spectroscopy, site maker displacement and molecular modeling methods. Investigations of the binding constant (K = 3.55 × 105 M−1, 295 K), the number of binding sites (n = 1.16), thermodynamic parameters (ΔG = 3.13 × 104 J·mol−1, ΔS = 364 J·mol−1·K−1and ΔH = −6.85 × 105 J·mol−1) for the reaction and changes to the binding sites and conformation in HSA in response to etomidate were presented. Results show that etomidate can bind HSA tightly through electrostatic forces, and the protein skeleton conformation and secondary structure changes thereby. This is the first spectroscopic report for etomidate–HSA interactions which illustrates the complex nature of this subject. [ABSTRACT FROM AUTHOR]

A series of benzophenone chromospheres and zinc(II) phthalocyanine dichromophores labeled poly (aryl benzyl ether) dendrimer (Gn-DZnPc(BP)8n,n = 1−2) were synthesized. Their structures were characterized by elemental analysis,1H NMR, IR, UV–vis and matrix-assisted laser desorption/ionization time-of-flight spectrometry (MALDI-TOF MS). Their photophysical properties were examined by steady-state and time-resolved fluorescence methods. Both the poly (aryl benzyl ether) dendrimer and BP terminal chromophores had a significant effect on photophysical properties of the zinc(II) phthalocyanine core. Time-resolved spectroscopic measurements indicated that the lifetime of benzophenone (donor) chromophore was longer than that of the zinc(II) phthalocyanine (acceptor). The fluorescence of the peripheral benzophenone chromophores was quenched by the phthalocyanine group attached to the focal point. All of these observations suggest that an intramolecular singlet energy transfer occurs inGn-DZnPc(BP)8nmolecules. The light-harvesting abilities of these molecules increased with generations due to an increase in the number of benzophenone chromophores. The energy transfer efficiencies wereca.0.49 and 0.68 for generations1and2, respectively, and the rate constants of the singlet-singlet energy transfer wereca.108 s−1. The rate constants changed inconspicuously with increase of dendron generations. The intramolecular singlet-singlet energy transfer is proposed to proceed mainly via a Förster-type interaction mechanism involving the dendrimer backbone as a scaffold to hold the peripheral benzophenone chromophores and the phthalocyanine core together. This dendrimer was an effective new energy transmission complex with high efficiency and could be used as a potential light-harvesting system. [ABSTRACT FROM AUTHOR]

To separate spiramycin from the crude sample of bitespiramycin, the optimal extraction conditions in single stage extraction had been obtained as follows: the temperature was 30-40°C, the concentration of phosphate solution was 0.3-0.4 wt.%, and the volumetric ratio of ester/aqueous was 2-3. A three-stage counter-current extraction technique had been utilized to improve extraction efficiency. The removal rate of spiramycin and the retention rate of bitespiramycin were as high as 79.14% and 92.41%, respectively. A theoretical model of three-stage counter-current extraction was introduced to calculate the results of the extraction and fitted the experimental data with satisfactory accuracy. [ABSTRACT FROM PUBLISHER]

The isobaric vapor-liquid equilibrium data for distillation have been measured for three binary systems of (1,2-butanediol(BD)+1,4-BD), (1,2-BD+2,3-BD), and (1,4-BD+2,3-BD) and for the ternary system of (1,2+BD+1,4-BD+2,3-BD) at 101.3 kPa. The thermodynamic properties of the vapor phase have been calculated with the Hayden-O’Connell equation in consideration of nonideality. The liquid activity coefficients have been satisfactorily correlated with the Wilson, NRTL and UNIQUAC models. The corresponding binary interaction parameters of the three models were calculated. Based on all the preceding results, a two-column distillation process was designed to obtain the required products with purity of 98% for industrial use. [ABSTRACT FROM AUTHOR]

Activity-guided fractionation for complement inhibitors led to the isolation of 24 known compounds from Anchusa italica. Chemical types include eight megastigmane compounds, five triterpenoid compounds, five lignan compounds, three flavonoid compounds, two alkaloid compounds and one phenthyl alcohol compound. Among which, a lignan (medioresinol), an alkaloid (5-hydroxypyrrolidin-2-one) and a flavonoid (5-hydroxyl-3', 4', 6, 7-tetramethoxy flavone) exhibited better anticomplementary effects with CH50 values ranging from 0.07 to 0.82 mM, which are plausible candidates for developing potent anticomplementary agents. [ABSTRACT FROM AUTHOR]

Vapor-liquid-liquid equilibria (VLLE) data were determined for the ternary system 1-butanol + water + 2,3-butanediol at 101.3 kPa. A binary heterogeneous minimum boiling azeotrope was found at 365.95 K with mass fractions of 0.526 and 0.474 for 1-butanol and water, respectively. A modified UNIQUAC model was used to predict VLLE by using experimental data, including VLE of 1-butanol + 2,3-butanediol, VLE of water + 2,3-butanediol, LLE of 1-butanol + water, and one LLE tie-line of 1-butanol + water + 2,3-butanediol. The experimental data were compared with the calculated values. The absolute average relative deviations (AARD) are 1.65%, 1.72%, and 2.22% for organic liquid phase, aqueous liquid phase, and vapor phase, respectively. It demonstrates an appropriate fit of the modified UNIQUAC model. [ABSTRACT FROM AUTHOR]

In this article, macro-porous resin, SP825, was used as adsorbent for the adsorption separation of erythromycin A (EA) and erythromycin C (EC). The effect of solution polarity and temperature on adsorption of EA and EC with their mixture was determined by batch adsorption experiments in detail. Adsorption isotherms were modeled by competitive Langmuir equations, selectivity coefficients were obtained, and thermodynamic parameters such as changes of Gibbs free energy, enthalpy, and entropy were calculated by van’t Hoff relationships. Then, dynamic adsorption and desorption separation experiments with the appropriate solution polarity and temperature obtained from the batch experiments were examined in a fixed-bed. Breakthrough curves were determined to understand the different dynamic adsorption performances for EA and EC. After the adsorption and desorption separation, the mass concentration ratio of EA to EC increased sharply from 9:1 to 25.3:1. [ABSTRACT FROM AUTHOR]

Bitespiramycin was purified by selective adsorption. The adsorption and desorption properties of bitespiramycin on six different macroporous resins (HZ806, HZ816, HZ820, HZ830, XAD16, and SP207) were compared systematically. According to the adsorption capacity and selectivity towards 4″-O-isovalerylspiramycin, HZ820 was chosen as the most suitable resin for bitespiramycin purification. The equilibrium data on HZ820 in a batch system were well described by Langmuir and Freundlich models. The film and pore diffusion model was successfully measured in batch adsorption kinetics. Dynamic adsorption and desorption experiments were also performed using a packed column of HZ820 to optimize the separation process of 4″-O-isovalerylspiramycin from aqueous solution. After being treated with HZ820, the 4″-O-isovalerylspiramycin content increased from 80.4% to 91.7%, and the 4″-O-isovalerylspiramycin III content increased from 41.7% to 64.4%. [ABSTRACT FROM PUBLISHER]

We examined the adsorption of aqueous erythromycin (EM) to the macroporous resin Sepabead SP825 in a series of batch experiments. The equilibrium data were well described by a Langmuir isotherm. The free energy, enthalpy, and entropy of adsorption were calculated, and a film and pore diffusion model was used to simulate the mass transfer mechanism, taking into account diffusion across the liquid film surrounding individual particles and diffusion within the resin particle. The model predictions were consistent with the experimental data and consequently were used to determine the mass transfer coefficients. [ABSTRACT FROM AUTHOR]