L'action Des Quelques Aldéhydes Sur La Laine

L'ACTION DES QUELQUES ALDÉHYDES SUR LA LAINE

PAR

SAVEL IFRIM

In the literature consulted there are no indications concerning the using of benzaldehyde, p-dimetilaminobenzaldehyde or anisaldehyde in wool chemistry.

Taking into account the properties of the aldehyde function, this paper studies the action of these aldehydes on wool. The electronic effects which appear in the case of the chemical structures of the aldehydes used to treat wool enhance the electronic density on the carbonylic oxygen and so the possibility that this atom to participate in reactions with the existing functional groups within keratin chemical structure appears.

The chemical changes that appeared in keratin have been evidentiated by solubility factors, from tests with urea-bisulphite and aqueous solution of sodium hydroxide 0,1 n. Comparing them with the factors obtained in the case of untreated wool, one can observe that aldehydes used reticulate keratin. The difference between these factors is explained by the different reactivity of the aldehyde functions determined by the +I effect on the metil groups existing within the p- dimetilaminobenzaldehyde and the anisaldehyde and of the nitrogen and oxygen atoms, which have free electrons, fact that doesn't exist in the case of benyaldehyde.

It is advisable to take into account the fact that wool treated with p- dimetilaminobenzaldehyde colors in a very beautiful and homogeneous shade of orange.

ASPECTS CONCERNING WET SPINNING OF ACRYLONITRILE- VINYL ACETATE-α-METHYL STYRENE-THERNARY COPOLYMER

VASILE BLAŞCU

In co-polymerization, reaction products are always non-homogeneous in composition due to the difference in monomer reactivity rates. Such heterogeneity in composition may have influence upon mechanical properties of copolymers. Such copolymer is ternary copolimer: acrylonitril-vinyl acetate-α-methyl styrene (polyacrylonitril - PAN) used in obtainement of Romanian PAN fibers.

In this paper we analyze the mechanochemical behaviour of this spinning copolymer.

THE MATHEMATICAL MODELING OF THE POSITION PARAMETERS OF A CAM

LILIANA FLORINA BUZESCU, MARIANA COCEA and FLORENTINA HARNAGEA

In this paper, one presents the method of finding of the function G(x), belonging to a Fourier series, which approximates the numerical values for the position parameters following the shift on the peg and a rotation angle, with the best accuracy. This analysis seems even more important, when we consider the fact most of the machines used in textile industry nowadays use a cam mechanism.

RESEARCH OF OBTAINING CONDUCTIVE FIBERS

*VLADAN KONCAR, LILIANA ROZEMARIE MANEA and

ANCA NECHITA

Conductive fibers were obtained using two experimental processes (melt spinning and coating process). In melt spinning process, polyaniline (PANI), polypyrrole (PP) and graphite were used in order to obtain conductive polypropylene (PP) based fibers with specific electrical and mechanical properties. PANI was treated using dodecylbenzene sulfonic acid (DBSA) to improve the solubility and the dispersion of PANI in xylene. PANI coating on PET yarns were performed by absorbtion of yarns through PANI solution. The electrical resistance and morphological characteristics of conductive yarns were investigated. These yarns are supposed to be used to create smart clothing, corrosion protection or conductive fabrics for electromagnetic shielding applications.

THE INFLUENCE OF COTTON TYPE CORE YARNS PROPERTIES ON KNITTED FABRICS STRUCTURE PARAMETERS

LILIANA ROZEMARIE MANEA, IULIANA GABRIELA LUPU, EMILIA FILIPESCU and MANUELA AVADANEI

In this paper have been performed the manufacturing technological possibilities of some knitted fabrics from core yarns having structure parameters and characteristics preestablished by the beneficiary. The correspondence ratios for the manufacturing similar knitted fabrics with those from 100% cotton yarns having the same fineness.

SOME APECTS OF THE INFLUENCE OF YARN LENGTHWISE DENSITY ON THE CLOTH COMPACTNESS DEGREE

DANIEL CHINCIU and *DORINA OANA

The compactness degree, considered as the most complex index that characterizes the cloths, includes all the basic technical and structural parameters, among which the yarn lengthwise density plays an important role.

This work presents the sense and intensity of the influence of the lengthwise density on the compactness degree, as well as the possibilities it offers to obtain stripped cloths with internal homogeneous structure.

BRAIDED STRUCTURE USED FOR REINFORCED CONCRETE BEAM

LUCICA CIOARĂ, IOAN CIOARĂ andELENA ONOFREI

Whenever advancing technology needs a combination of properties that no single material can provide, the composite materials are chosen. In the last time the textile composites are more and more used in architecture and construction, because of their advantages compared with another composite structures.

A textile composite is made of a textile reinforcement structure (preform) and a matrix material. This paper presents a study on the possibility to use two-dimensional braided strusture as preform and polypropylene as thermoplastic resin in order to obtain a textile composite used for reinforced concrete beam. Tri-axial braids have been obtained by inserting additional filamentary glass yarns in the axial direction of the braided structure. Polypropylene filamentary yarns were used as braiding yarns.

The textile composites must have certain properties as stiffness or flexibility, high strength and low density. These properties are functions of reinforcement structure and matrix properties but also of the glass fibre/polypropylene ratio. So the braided structure must be designed so that a certain glass fibre/ polypropylene ratio to be obtained.

ON SOME ELEMENTARY COMPONENTS OF THE CLOTH STRUCTURE

*MARILENA RĂVAŞ and DANIEL CHINCIU

In this paper the fabric geometrical structure elements are redefined. The motivation for this attempt is the fact that the specialized literature offers for these element definitions and characterizations sometimes contradictory.

By their content and way of description, the proposed definitions contribute really at the design and dimensioning of the elements of the fabric internal structure.

WEAVE INFLUENCE CORRELATED WITH THE COMPACTNESS DEGREE, ON THE YARN SYSTEMS DENSITY IN CLOTHS WITH COMBINATIONS WEAVES

*DORINA OANA and DANIEL CHINCIU

The stripe fabrics obtained by combining weaves with different mean float and equal compactness present an inhomogeneous character that influences the shape stability of the cloth yarns. This work presents a of methods to improve the inhomogeneous character of the cloth by using different yarn counts, depending on weave, in correlation with the compactness degree.

EXPERIMENTAL LOOP MODEL FOR WARP KNITTED FABRICS

MIRELA BLAGA

In this paper, development of a new simple and accurate mathematical loop model for two bar warp knitted structures will be presented. Results are based on extensive theoretical and practical studies carried out on warp knitted structures. The accuracy of the results obtained from the new loop model compared with experimental ones achieved will be shown.

AN ANTHROPO-MORPHOLOGICAL CHARACTERIZATION FOR STOUT FEMALE, AFTER AGE CRITERION

EMILIA FILIPESCU, MANUELA AVADANEI AND LILIANA MANEA

In order to characterize stout female from anthropo-morphological point of view there were used primary from a sample with 22 subjects. For this research there have been selected some morphological indicators, which characterize body posture, shoulders height, proportion, conformation, for the whole sample and the small ones made after age criterion.

The values for all statistical parameters (the whole sample and small ones) allow an anthropo-morphological characterization for the representative body to obtained after this study.

The results of this research are primary information necessary to use in pattern cutting activity besides the conformation, posture, and proportions for female adult population.

TEXTILE FINISHES WITH POLYMER BLENDS

AURELIA GRIGORIU, *DOINA MACOCINSCHI and *DANIELA FILIP

Two types of polymer blends were applied on a textile material (100% cotton, Ponor B). The first one consists of blends of poly(ether sulfone)s (Udel-type) with molecular weights of 1,700 and 3,500 g/mol and cholesteryl palmitate as a low molecular weights component. The second one comprises polytetrahydrofuran with molecular weights of 1,000 and 2,000 g/mol and the same additive. The hydrophilicity, air permeability, tensile strength, humidity, hygroscopicity and porosity were determined. These finishes determined a variety of physico-mechanical qualities which enable these products to be used in a wide range of applications.

INTERACTION OF MALEIC ACID COPOLYMERS WITH CATIONIC DYES IN AQUEOUS SOLUTION

2. METACHROMATIC INTERACTION OF A HYDROPHOBIC COPOLYMER STUDIED BY THE UV-Vis ABSORBTION SPECTROSCOPY

ELENA CÎDU, *GABRIELLE CHARLOTTE CHITANU and AURELIA GRIGORIU

In the paper is described the metachromatic phenomenon in systems that include poly-electrolytes and dyes, using the UV-absorbtion spectroscopy as method of study. Experimental data is presented, regarding the metachromasy produced by the maleic acid-styrene copolymer, as sodium salt (NaM-S), on a thiazine dye – Methylene Blue (MB) – and on a triarylmethanic dye – Victoria Blue B (VBB), in aqueous solution. It has been observed that in the case og the MB/NaM-S system the metachromatic shift is hypsochromic, whereas in the case of the VBB/NaM-S system the metachromatic shift is bathochromic. Then are discussed the differences of behavior between the two maleic polyelectrolytes, as well as the parameters that influence the metachromatic phenomenon in these systems.

HIGH FREQUENCY COLD PLASMA DECONTAMINATION OF THE ORGANIC SUPPORTS FROM THE COMPOSITION OF THE MUSEUM PIECES

GHIOCEL IOANID, *DORINA PĂRPĂUŢĂ,

**SIMONA DUCA, ***AURELIA GRIGORIU

The museum institutions get often confronted with the biodegradation phenomenon generated by microorganisms, the heritage objects made of organic materials (leather, textile, wood) being the most damaged.

The classical decontamination treatments which make use of gamma radiation or of certain chemical compounds have proved to be noxious for both, pieces and users.

Under these circumstances, the present work is dealing with another method used to kill the microorganisms, namely the utilization of the high frequency cold plasma. The efficiency of the cold plasma in the organic supports decontamination depends on the duration of carried out both before and after the treatment. This work also includes a number of physical investigations revealing that the leather supports preserve their integrity after a 120 min treatment strictly conducted at a temperature below 50º C, a pressure of 10-1 mbarr and a frequency of 1,3 MHz.

THE IMPORTANCE OF COMMUNICATION IN THE PROFESIONAL INTEGRATION PROCESS

MONICA VOICU and RALUCA PETRONELA LĂZĂRESCU

The paper illustrates the importance of communication between manager and employee during the professional integration process. The authors show the necessity of implementation into companies of a professional integration system that helps the manager to improve his work relation with the employees since the beginning of their arrival into company. The paper contains researches regarding the professional integration in Romanian companies and comes with new ideas concerning the improvement of the process.

IMPLEMENTING TOTAL QUALITY MANAGEMENT USING THE ORGANIZATIONAL CULTURE: A NEW FRAMEWORK

DANA CORINA DESELNICU AND COSTACHE RUSU

This article presents a cultural theory of why planned organizational change efforts, such as total quality initiatives, often fail. The theory suggests that employees resist total quality because their assumptions and beliefs, about the organization – which form the organizational culture – constrain understanding and create opposition to radical change.

The article proposes a dynamic model in which successful implementation of organizational transformation is dependent on management’s ability to re-frame the change over time. Implementation is best accomplished through a series of middle-range changes that are large enough to overcome organizational inertia and relieve organizational stress, but not so large that members believe the proposed change is unobtainable or undesirable.