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Chemical Formulas

Chemical Formulas

A chemical formula presents information about the proportions of atoms constituting a particular chemical compound or molecule, mainly using symbols of elements and numbers. At times other symbols, such as dashes, parentheses, brackets, commas, plus, and minus signs, are also used. A chemical formula can be one of three types – molecular, empirical, and structural.

Ionic Compounds: Formulas and Nomenclature

Ionic Compounds: Formulas and Nomenclature

An element composed of atoms that readily lose electrons (a metal) can react with an element composed of atoms that readily gain electrons (a nonmetal) to produce ions through complete electron transfer. The compound formed by this transfer is stabilized by the electrostatic attractions (ionic bonds) between the oppositely charged ions.

Experimental Determination of Chemical Formula

Experimental Determination of Chemical Formula

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Molecular Compounds: Formulas and Nomenclature

Molecular Compounds: Formulas and Nomenclature

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Pulse

Pulse

When the heart pumps blood out, arterial elastic fibers play a crucial role in sustaining a high-pressure gradient. They expand to accommodate the received blood and then recoil - a process known as the pulse that can be either manually palpated or electronically quantified. Despite a reduction in its effect with increased distance from the heart, elements of the pulse's systolic and diastolic components persist, observable even at the arteriole level.
The pulse serves as a clinical...

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Chinese Herbal Retention Enema for the Treatment of Ulcerative Colitis

Chinese Herbal Retention Enema for the Treatment of Ulcerative Colitis

Published on: May 16, 2025

Evaluation of herbal formulas by pulse analysis method.

Wei-Kung Wang¹, Tse-Lin Hsu, Jian-Guo Bau

¹Biophysics Laboratory, Institute of Physics, Academia Sinica, Nankang, Taipei, Taiwan 11529, China.

Acta Pharmacologica Sinica

|January 28, 2003

Summary

Pulse analysis quantitatively detects herbal formula differences. This method distinguishes component variations in traditional Chinese medicine, offering insights into their physiological effects.

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Area of Science:

Pharmacology
Traditional Chinese Medicine
Biomedical Engineering

Background:

Chinese herbal formulas often have subtle variations.
Understanding these differences is crucial for efficacy and safety.
Pulse analysis is a traditional diagnostic method with potential for objective assessment.

Purpose of the Study:

To differentiate component variations between two similar herbal formulas using pulse analysis.
To investigate the relationship between herbal composition and pulse wave characteristics.
To establish pulse analysis as a quantitative method for evaluating herbal formula modifications.

Main Methods:

Two modified Liu-Wei-Dihuang formulas (A and B) were administered to Wistar rats.
Blood pressure pulses were recorded from the rat tail artery.
Fourier analysis was applied to the pulse data to analyze frequency components.

Main Results:

Formula A (Bai-Wei-Dihuang) showed increased C1 and decreased C4, C5 harmonic proportions.
Formula B exhibited increased DC (C0) and decreased C2-C6 components.
Distinct spectral changes correlated with specific herbal additions/omissions.

Conclusions:

Pulse analysis can distinctly and quantitatively detect component adjustments in herbal formulas.
This method provides an objective approach to evaluating modifications in traditional Chinese medicine formulations.
Fourier analysis of pulse waves offers a valuable tool for quality control and research in herbal medicine.