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Computational modeling is a useful approach for the characterization, development, and validation of desorption chromatography. Batch and dynamic desorption experimental results are helpful for the selection of an appropriate desorbent and the design of a desorption processes. In this study, we used an aqueous HCl solution ranging from 0.030 mol/L to 0.060 mol/L to desorb cAMP (adenosine 3′,5′-cyclic monophosphate) from a presaturated anion exchange resin (D-13). Good results were obtained in terms of the desorption rate and cAMP recovery. Subsequently, general rate model (GRM) that incorporated counter-ion flux was used to describe the desorption kinetics of the batch experiments. The superficial rate constant, K d , of the cAMP/HCl reaction on activated ion exchange sites inside the resin was estimated as 0.130 L/(mol/s) using the least squares fitting method, which was then applied for predicting the dynamic desorption processes. The pore diffusion coefficients for Cl − and cAMP were estimated as 1.57×10 −9 and 5.71×10 −10 m 2 /s, respectively. We verified the applicability of this GRM model to a column desorption process by experimentally investigating the effects of the HCl concentration, flow rate, and column aspect ratio on column desorption. The experimental results could be predicted successfully using the GRM model. The validated GRM may provide an important basis for future scale-up of the cAMP desorption process.

A novel polar macroporous adsorption resin (AX-1) has been applied for separation of d -lactic acid (DLA) from aqueous solutions in a fixed-bed chromatographic column. The adsorption equilibrium and kinetics were investigated experimentally. A column model was subsequently established and validated by comparison of the simulation results to the experimental data obtained at different operating conditions in terms of feed flow rates and initial concentrations as well as bed heights. At the end of this work, the recycling studies were carried out. It was found that the saturated resin could be washed out DLA completely and repeated use by 353 K hot water. The results show that the AX-1 resin has a high adsorption capacity to DLA while no retention to sulfate ion. Based on this kind of resin, a green-production refining process could be established since only water is added in the entire separation process.

Computational and theoretical modeling has become an important tool for the characterization, development and validation of packed beds. Relevant breakthrough curves would provide much valuable information on designing a fixed bed adsorption process in field applications. In this study, the hydrodynamic properties involved in the Navier–Stokes flow equation, such as velocity, pressure and permeability, in a packed bed were investigated. A two dimensional (2D) model based on the convection/diffusion approach theory and the Nernst–Planck model was adopted to describe the breakthrough curves of adenosine 3′,5′-cyclic monophosphate (cAMP) adsorption onto a porous resin adsorbent, SD-13, from an aqueous solution. The relevant ordinary partial equations were solved in COMSOL Multiphysics Software friendly and efficiently. Column experiments were performed at different conditions to verify the model, and the results indicated that the model describes well the breakthrough curves. The behaviors of exchanged counter-ion (Cl − ) in cAMP adsorption experiments were also predicted well.

The solubility of l -phenylalanine in water and binary mixtures (methanol + water and ethanol + water) at temperatures ranging from 288.15 to 318.15 K was investigated. The results obtained from these measurements were correlated with the temperature and the molar fraction of water by the combined nearly ideal binary solvent (CNIBS)/Redlich–Kister(R–K) model and the semiempirical Apelblat model. Both of the models demonstrated good fitting with the experimental data, while the CNIBS/R–K model gave a more accurate prediction. In addition, the thermodynamic properties of the solution process, including the Gibbs energy, enthalpy, and entropy, were obtained using the van’t Hoff equation and the Gibbs equation. The experimental results showed that water was a better solvent for l -phenylalanine than methanol and ethanol, which could thus be used as effective anti-solvents in the crystallization process. For all the cases studied, the values of both the standard molar enthalpy change and standard molar Gibbs energy change of solution were positive, which indicated that the process was endothermic and not spontaneous.

In a batch equilibrium system, the maximum adsorption capacity of cAMP onto an anion-exchange resin reached 0.1718, 0.1956, 0.2764 and 0.3437 g g −1 at 283, 293, 303 and 313 K, respectively. The adsorption data obtained were well described by the Langmuir isotherm. In the batch kinetic system, Fick diffusion, pseudo first-order and pseudo second-order models were applied to simulate the experimental kinetic data. The results revealed that the Fick model best described the adsorption process, and clearly predicted the intraparticle distribution of the concentration. The effective diffusion coefficients ( D e ) for 283, 293, 303 and 313 K were 0.37 × 10 −10 , 0.51 × 10 −10 , 0.86 × 10 −10 and 1.41 × 10 −10 m 2 s −1 , respectively. The thermodynamic parameters such as Δ G 0 , which were all negative, indicated that the adsorption of cAMP onto the anion-exchange resin was spontaneous and the positive value of Δ H 0 (+8.66 kJ mol −1 ) showed that the adsorption was an endothermic reaction.

An improved, simple gas chromatography –flame ionization detection (GC–FID) method was developed for measuring the products of acetone-butanol-ethanol (ABE) fermentation and the combined fermentation/separation processes. The analysis time per sample was reduced to less than 10 min compared to those of a conventional GC–FID (more than 20 min). The behavior of the compounds in temperature-programmed gas chromatographic runs was predicted using thermodynamic parameters derived from isothermal runs. The optimum temperature programming condition was achieved when the resolution for each peak met the analytical requirement and the analysis time was shortest. With the exception of acetic acid, the detection limits of the presented method for various products were below 10 mg/L. The repeatability and intermediate precision of the method were less than 10% (relative standard deviation). Validation and quantification results demonstrated that this method is a sensitive, reliable and fast alternative for conventional investigation of the adsorption-coupled ABE fermentation process.

Simultaneous determination of organic acids using ion-exclusion liquid chromatography and ultraviolet detection is described. The chromatographic conditions are optimized when an Aminex HPX-87H column (300 × 7.8 mm) is employed, with a solution of 3 mmol/L sulfuric acid as eluent, a flow rate of 0.4 mL/min and a column temperature of 60°C. Eight organic acids (including orotic acid, α-ketoglutaric acid, citric acid, pyruvic acid, malic acid, succinic acid, lactic acid and acetic acid) and one nucleotide are successfully quantified. The calibration curves for these analytes are linear, with correlation coefficients exceeding 0.999. The average recovery of organic acids is in the range of 97.6% ∼ 103.1%, and the relative standard deviation is in the range of 0.037% ∼ 0.38%. The method is subsequently applied to obtain organic acid profiles of uridine 5'-monophosphate culture broth fermented from orotic acid by Saccharomyces cerevisiae. These data demonstrate the quantitative accuracy for nucleotide fermentation mixtures, and suggest that the method may also be applicable to other biological samples.

Paramorphocoris henanensis Bai & Heiss, sp. nov. ( Figs. 1���6 ) Type material. Holotype: female, China, Henan, Xinyang, 27. IV. 2014, B. X. Bai leg. (IMNU); paratype female collected with holotype, deposited in the collection of EH at the Tiroler Landesmuseum (CEHI). Specimens are designated and labeled accordingly. Description of female holotype. Color: Body blackish brown, incrustation grayish brown; eyes reddish; head, thoracic tergites and pleura, most of abdominal tergites, connexiva, lateral parts of third to seventh sterna covered by incrustation; antennae and legs beset with adpressed setae (Fig. 1). Head. Longer than width across eyes; genae slightly notched anteriorly, reaching basal one-third of first antennal segment; clypeus strongly raised anteriorly, with tubercle near apex; antenniferous tubercles short, dilated, apices acute, divergent anteriorly; eyes small, convex laterally; postocular lobes anterolaterally subparallel with few small conical tubercles, then constricted posteriorly; vertex with granulate median ridge (Figs. 4, 5); antenna 1.93 times as long as width of head across eyes; rostrum shorter than head, rostral groove narrow and deep, closed posteriorly (Fig. 6). Pronotum. Width 3.12 times as wide as long, narrowing anteriorly, anterolateral angles protruding forward beyond collar; collar narrow; disc with deep rounded pit at median of anterior half, posteriorly followed by longitudinal groove flanked by 2 (1 + 1) small rounded smooth elevations (Figs. 1, 3); lateral margins raised and granulate; posterior margin slightly convex, separated from mesonotum by deep furrow. Mesonotum. Wider than pronotum; separated from metanotum by 2 (1 + 1) deep furrows lateral of the median, elongate, smooth ridge extending to metanotum, depressed anteriorly and raised posteriorly, strongly constricted at posterior margin; elevated structures adjacent to median ridge with 2 (1 + 1) smooth, high longitudinal ridges; granulate surface and carinate lateral margins. Metanotum. Wider than mesonotum; median ridge with a deep longitudinal sulcus, flanked by 2 (1 + 1) deep depressions; surface laterad of median ridge with 2 (1 + 1) high longitudinal granulate ridges, lateral margins forming granulate carinae; separated from mtg I by narrow transverse sulcus. Mtg I+II. Mtg I with 2 (1 + 1) high transverse ridges, with deep median depression between them; separated from mtg II by transverse sulcus; mtg II sloping sideways, depressed at middle, posterior margin sinuate and carinate (Figs. 1- 3). Abdomen. Tergal plate consisting of mtg III - VI; anterior margin medially produced, posterior margin truncate, lateral margins slightly rounded; median carina on mtg III - V, moderately raised, tapering on mtg VI; scent gland openings on mtg IV and V distinct; surface laterad of median ridge with usual pattern of large and small callous spots; surface of deltg II-VII subhorizontal, deltg II and III completely fused, others separated by fine sulci; posterolateral angles of deltg II to VI not protruding, VII angularly produced; paratergites lobate; terminal part of abdomen as in Figs. 1,2. Venter. Spiracles II to IV ventral, V to VII lateral and visible from above, VIII terminal; prosternum raised medially; mesosternum and metasternum with subreactangular median depressions; sterna III to VI raised along posterior border, depressed along anterior border with triangular smooth spots medially, flanked by 2 (1 + 1) large, transversely ovate shallow depressions bearing 2 (1 + 1) round callous spots; followed laterally by 4 (2 + 2) smaller round callous spots. Legs. Slender, preapical comb on fore tibia present, claws without pulvilli. Measurements. Holotype female: length 4.95; maximum width of abdomen 2.35; head, length 1.0, width 0.75; pronotum, length 0.4, width 1.25; width mesonotum 1.6; width metanotum 2.0; length of antennal segments I���IV = 0.45, 0.25, 0.45, 0.3. Paratype female: length 5.05; maximum width of abdomen 2.35; head, length / width 1.0 / 0.75; pronotum, length / width 0.5 / 1.25; width mesonotum 1.65; width metanotum 2.0. Etymology. This specific name refers to the province where this species was collected. Distribution. China (Henan Province)., Published as part of Cui, Jianxin, Bai, Xiaoshuan, Heiss, Ernst & Cai, Wanzhi, 2015, A new apterous genus of Carventinae (Hemiptera: Aradidae) from China, pp. 143-146 in Zootaxa 3980 (1) on pages 144-145, DOI: 10.11646/zootaxa.3980.1.9, http://zenodo.org/record/239185

Paramorphocoris Bai & Heiss, gen. n. Type species: Paramorphocoris henanensis Bai & Heiss, sp.n. Diagnosis. Apterous. Medium sized. Body elongate ovate. Dorsal and ventral surfaces partly covered by grayish incrustation of unique pattern, only lateral borders with few short bristles. Head longer than width across eyes; genae slender, produced over clypeus; antenniferous tubercles stout, conical, apically pointed; eyes small, semiglobose, with convex face; postocular lobes anterolaterally subparallel with some distinct tubercles, converging posteriorly to constricted neck; vertex and clypeus together forming a median ridge; antennae long and slender, first and third segments of subequal length, second shortest, first stout and clavate, second and third cylindrical, fourth fusiform; rostrum arising from a slit-like atrium, not reaching limits of rostral groove. Pronotum attenuated anteriorly, anterolateral angles protruding anteriorly beyond collar, disc with narrow medial groove. Meso- and metanota medially fused to narrow, high longitudinal ridge strongly constricted at middle and flanked by deep depressions, laterally separated by furrows, metanotum separated by furrows from mtg I, mtg II and triangular fused deltg I+II; lateral margins of thoracic segments incrassate, deeply cleft between pro-, meso-, and metanota. Mtg I separated from mtg II by a furrow. Tergal plate of fused mtg III-VI pentagonal. Tergite VII strongly elevated posteriorly (Fig. 2) Thoracic sterna with processes pointing to coxae. Legs long and slender, without spines trochanters fused to femora. Distribution. China. Etymology. The generic name reflects the similarity to Morphocoris, >paraRemarks. General habitus, head and thoracic structures of the new genus resemble those of the Oriental genus Morphocoris Kormilev 1980 (Kormilev 1977 (as Glyptomorpha); Heiss 1982), which comprises 3 species from Thailand, Malaysia, and India. Compared with a male paratype of Morphocoros thailandicus in the collection of the co-author (EH) (no female specimen has ever been illustrated), the latter is distinguished from Paramorphocoris henanensis gen. et sp. nov. by a much wider and less constricted median ridge of meso- and metanotum without a longitudinal sulcus, by the very deep oval lateral excavations of metanotum, the deeper median depression of mtg I+II showing 2 longitudinal carinae at its bottom on mtg II, the straight anterior margin of the tergal plate, and the deep median excavation on mtg III in continuation of that of mtg I+II flanked by raised margins. The elevations and deep cavities cannot be recognized from Kormilev���s 1977 only illustration of this species (p. 618, Fig. 19)., Published as part of Cui, Jianxin, Bai, Xiaoshuan, Heiss, Ernst & Cai, Wanzhi, 2015, A new apterous genus of Carventinae (Hemiptera: Aradidae) from China, pp. 143-146 in Zootaxa 3980 (1) on pages 143-144, DOI: 10.11646/zootaxa.3980.1.9, http://zenodo.org/record/239185, {"references":["Kormilev, N. A. (1980) Homonymy in the Aradidae. Pacific Insects, 22, 328.","Kormilev, N. A. (1977) Aradidae from the Oriental and Australian regions in the collections of the California Academy of Sciences, San Francisco (Heteroptera: Aradidae). Transaction of the American Entomological Society, 13, 603 - 622.","Heiss, E. (1982) New and little known Aradidae from India in the Museum d'Historire naturelle de Geneve (Heteroptera). Revue Suisse de Zoologie, 89, 245 - 267."]}