Research Article
Stereochemistry of D, L-ribitol Iminocyclitols Between 4 and 2 Dimensions
Carmen-Irena Mitan*
,
Emerich Bartha
Issue:
Volume 14, Issue 5, October 2026
Pages:
142-151
Received:
8 September 2026
Accepted:
16 September 2026
Published:
29 September 2026
Abstract: The transformation from 4D to 3D and 2D exemplified recently with Lie algebra and Hopf fibration on cis, trans-ee, trans-aa stereochemistry, now is demonstrated with hypersphere trigonometric equations for calculation dihedral angles θHnHn+1 [deg] from carbon chemical shift δCn [ppm], then the vicinal angle ϕ [deg] and the other five possible dihedral angles θHnHn+1 [deg] for one known vicinal coupling constant 3JHnHn+1 [Hz]. Cis, trans-ee and trans-aa stereochemistry placed on six sets angles on two units have trans-ee4, 1 stereochemistry under 2D dimension on unit S and trans-ee3, 2 stereochemistry particularized with algebraic equations on unit U under 4D. Both trans-ee stereochemistry representing a great example for continuum transformation for hypersphere to torus. B2 root system θ = 150 [deg] as alternative model for building unit under Hopf fibration, along A2 root system θ = 120 [deg] unit will be disclosed, the second one ensuring also relationships between dihedral θHnHn+1[deg] and vicinal angles ϕ[deg]. Three pair of sets angles representative for five membered rings simulated for a vicinal coupling constant, sets A, B - dihedral and vicinal angles, set C used to build unit U2 with set A and B calculated with 3α + 2β, and pair of sets A and B of unit S1 calculated with 3α + 3β.
Abstract: The transformation from 4D to 3D and 2D exemplified recently with Lie algebra and Hopf fibration on cis, trans-ee, trans-aa stereochemistry, now is demonstrated with hypersphere trigonometric equations for calculation dihedral angles θHnHn+1 [deg] from carbon chemical shift δCn [ppm], then the vicinal angle ϕ [deg] and the other five possible dihed...
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Research Article
Open-Pan Evapoconcentration Kinetics and Physicochemical Characteristics of Oil Palm Wine Syrups
Issue:
Volume 14, Issue 5, October 2026
Pages:
152-160
Received:
27 August 2026
Accepted:
9 September 2026
Published:
20 October 2026
DOI:
10.11648/j.sjc.20261405.12
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Abstract: Oil palm wine is highly perishable, and conversion into syrup offers a technically accessible route for local value addition. This study described open-pan evapoconcentration profiles and the immediate physicochemical quality of syrups prepared from four identified batches of oil palm wine. For each batch, 2 L of wine were heated at a nominal hotplate setpoint of 80°C under regular manual stirring. Apparent total soluble solids were measured every 20 min, and five nonlinear equations were compared using the root mean square error, coefficient of determination, corrected Akaike information criterion, and physical admissibility of the fitted parameters. The syrups were characterized for pH, titratable acidity, moisture, dry matter, and water activity immediately after processing. Apparent soluble solids increased from 6.97-10.00°Brix to 74.25-87.77°Brix within 200-260 min, corresponding to concentration factors of 8.18-10.65. Apparent syrup recovery ranged from 6.83 to 11.24 g per 100 mL of feed. A simplified evaporation-balance equation best represented batches S1 and S4, whereas a power-law equation described S2 and S3; the selected fits gave R2 values of 0.9713-0.9944 and root mean square errors of 1.434-2.976°Brix. Final pH ranged from 3.92 to 4.08 and titratable acidity from 0.36 to 0.91 g acetic acid equivalents per 100 g. Water activity separated the products into two lower-moisture syrups (0.472-0.482) and two higher-moisture syrups (0.660-0.704). The results establish the feasibility of producing highly concentrated oil palm wine syrup and identify simple nonlinear equations that can support endpoint control. Replicated runs with direct product-temperature measurement and standardized evaporation geometry are required for process optimization.
Abstract: Oil palm wine is highly perishable, and conversion into syrup offers a technically accessible route for local value addition. This study described open-pan evapoconcentration profiles and the immediate physicochemical quality of syrups prepared from four identified batches of oil palm wine. For each batch, 2 L of wine were heated at a nominal hotpl...
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