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Klára Hódi

Publications and source records attributed to Klára Hódi.

7 recordsLinked to original sources
PubMed2005

[Monitoring the temperature distribution during dielectric drying].

Microwave assisted vacuum drying offers never questioned advantageous and it is getting more and more popular lately. In spite of its uniqueness there is a rightful resistance and mistrust because the temperature distribution of the workload is far from being homogeneous as a result of the existing inhomogeneous electromagnetic field. The aim of this study is to survey the heat thus field distribution in the workload to prevent local overheating that endangers the quality of the pharmaceutical product. Thermography as a non perturbing thermometrical method was used to map the heat distribution in the workload. To get a 3D information Teflon layers were used to form cross-sectional and photogenic surfaces about the dusty blend and a purpose-developed software to evaluate qualitatively the IR pictures.

Electricity↗
PubMed2005

[Preparation and investigation of gemfibrozil + dimethyl-beta-cyclodextrin products and solid dosage forms].

Gemfibrozil is a lipid-regulating active substance. Dimethyl-beta-cyclodextrin products were prepared from this sparingly soluble pharmacon by means of methods such as physical mixing, kneading, spray drying and ultrasonication. Solid dosage forms (hydroxypropylmethyl cellulose /HPMC/ capsules and tablets) were prepared from the selected products on the basis of their dissolution profile and the in vitro membrane diffusion results. This publication details the results of electronmicroscopic morphological studies, particle size analysis and wetting contact angle determinations, and also the preparation and examination of the resulting solid dosage forms.

Diffusion↗
PubMed2003

[Benefit of microwaves in case of heat-sensitive agglomerate drying].

The microwave assisted vacuum drying of heat-sensitive materials is increasing in the pharmaceutical industry since the eighties. This paper deals with results of two experiment series obtained on a laboratory scale single pot dryer (Collette Ultima 251). Firstly water was heated up to the boiling point exclusively by predetermined microwave energy and then by various wall temperatures in order to determine the convection efficiency of the system. The experiments were carried out at fixed pressure level (80 mbar) and with optimum bowl load (15 kg). According to the demonstrated idea each single pot system efficiency can be specified at any type and quantity of load. With the help of the presented results the second experiments were designed to compare the microwave and convection efficiency of the single pot system during granule drying. A placebo granule was dried either by an exclusive convection or microwave method up to the determined LOD (< 0.5%). According to the tests extreme high wall temperature (85 degrees C) had to be used to achieve the same drying time--and efficiency--as with the usage of dielectric heating. Based on the results it can be stated that the shorter drying time under favourable conditions is the advantage of microwave radiation over the conventional technique.

Drug Industry↗
PubMed2003

[The effect of surface phenomena on the processing of solid materials. I. Theoretical basis of surface phenomena of solid materials].

The functions of friction and adhesion in the processing of solid materials were evaluated in our work. The first part of our study dealt with the theoretical basis of these phenomena. The work of Podczek was used as a guideline. The negative and positive effects of these parameters were emphasized. The types of adhesion were discussed. The different types of forces (capillary, Lifshitz-van der Waals, electrical, etc.) and several other parameters (surface free energy, roughness, particle size and shape) causing these effects were analysed. Different mathematical models which can be used for the determination of surface free energy, adhesion force and spreading coefficient were considered.

Capillary Action↗
PubMed2003

[The effect of surface phenomena on the processing of solid materials. II. Experimental evaluation of surface phenomena of solid materials].

The functions of friction and adhesion in the processing of solid materials were evaluated in our work. The second part of our study dealt with some practical examples from our practice. Indomethacin was used for the examination of adhesion, dimenhydrinate for the study of friction, and metronidazole for the determination of the spreading coefficient. Several technological methods (coating, granulation, pelletization and tableting) were used. The positive effects of the processes on the various phenomena (surface free energy, adhesion force and spreading coefficient) were emphasized. The influences of alteration in the parameters on the flowability, compressibility, compact texture, etc. were assessed.

Crystallization↗
PubMed2003

[The generic Research and Development possibilities after Hungary accessed th European Patent Convention].

January 1, 2003 Hungary became a member of the Munich Convention on the Grant of European Patents (European Patent Convention, EPC). As from January 1, 2003 European patents may be claimed and obtained also for Hungary and European applications may be filed with the Hungarian Patent Office as well. This paper focuses on the exceptional generic R&D possibilities which can harmonize in harmony with all the claims of the Union in spite of the fact that it does not follow general European limitations and practises. Based on the amended Hungarian Patent Law (No. XXXIII of 1995 on the Protection of Inventions by Patents; Article 19 (6)b)) the exclusive right of exploitation shall not extend to acts done for experimental purposes relating to the subject matter of the invention, including experiments and tests necessary for the registration of medicines as well. The national and international legal history and background of the operative Hungarian Patent Law are also presented roughly. The paper deals with the divergence of the originator-generic industry and the EU-USA industry and with the incoherence within the EU itself on the early testing permissions and limitations.

Europe↗