Effects of W Addition on the Electrochemical Behaviour and Passive Film Properties of Fe-Based Amorphous Alloys in Acetic Acid Solution

The electrochemical behaviour and passive film properties of Fe–Cr–Mo–W–C–B–Y amorphous alloys in acetic acid solution were investigated. The potentiodynamic polarisation and Nyquist curves demonstrated that W addition significantly enhanced the corrosion resistance. Mott–Schottky plots and angle-resolved X-ray photoelectron spectra indicated that passive films with different W contents exhibited dipolar(p–n) semiconducting characteristics separated by flat-band potentials. The outer and inner oxide layers of the passive films were modified by reducing the acceptor and donor densities. Moreover, W addition favoured the formation of a thicker and more stable passive film to inhibit the dissolution of alloy elements.     

Les fards rouges cosmétiques et rituels a base de cinabre et d'ocre de l'époque punique en Tunisie: analyse, identification et caractérisation

Natural antique colorants include mainly red pigments such as cinnabar and ochre. These archeological pigments were used especially as funeral and cosmetic makeup and are a material proof of handicraft activities and exchanges. The identification and characterization of a group of punic colorants, corresponding to samples discovered during excavations at several Tunisian archeological sites (Cartage, Ksour Essef, Kerkouane, Bekalta, Makthar, Bou Arada), were conducted using the least destructive analysis techniques such us scanning electron microscopy coupled to X-ray fluorescence microprobe, direct current plasma emission spectroscopy, atomic absorption spectrometry, Fourier transform infrared spectrometry and X-ray diffraction. Eleven natural red colorants from punic period were subject to this investigation and were compared to contemporary substances. Five colorants were cinnabar and the other six were ochre.     

Cosmetic use formulations containing pentyl rhamnoside and cetyl rhamnoside

For the first time, we report here the synthesis and use of pentyl and cetyl rhamnoside as cosurfactant or surfactant, respectively, and their evaluation in cosmetic formulations. l-rhamnose is more reactive than d-glucose in direct acetalization with long alkyl chains of alcohol, because of its higher lipophilicity, whereas for short alkyl chains, glucose and rhamnose are equivalent. Furthermore, pentyl rhamnoside could be used as a new non-toxic cosurfactant to formulate microemulsions. Finally, a white continuous aqueous phase emulsion and a liquid soap were evaluated for cosmetic uses. These new formulations showed very good cosmetic properties with high hydration properties and rapid cutaneous penetration.     

纳米化妆品及其研究进展

针对纳米技术制造的纳米级化妆品,从概念的由来与明确、技术原理、不同功能的作用机理、当前存在的主要问题与应对措施以及化妆品中常用的几种可纳米化的成分进行阐述,最后对纳米级化妆品今后的发展进行了展望。     

食料对烟草甲生长发育及繁殖的影响

研究了麦粒、营养麦片、面粉、烤烟和甘草等5种食料对烟草甲生长发育与繁殖的影响.实验观测了烟草甲各虫态的生长发育历期、各虫态的存活状况以及成虫的产卵情况,并对其净生殖率R0、内禀增长率rm和种群增长周限λ等生命表参数进行了考查.结果表明:麦粒、营养麦片、面粉是其适宜寄主,种群趋势指数分别为35.45、39.77和32.84,而甘草的种群趋势指数仅为7.55.对不同食料进行营养成分分析后发现:食料的可溶性总糖和蛋白质含量对烟草甲的生长发育和繁殖影响较大,脂肪的变化影响小;同时,颗粒状和粉末状食料更适合烟草甲的生长发育及繁殖.     

Green chemistry procedure for the synthesis of cyclic ketals from 2-adamantanone as potential cosmetic odourants

Some cyclic ketals derived from 2-adamantanone were obtained in excellent yields by microwave activation under solvent-free conditions, as a 'green chemistry' procedure. A number of experiments were performed to evaluate the most efficient catalytic conditions. The best results were obtained using a simple heterogeneous mixture of reagents and p -toluenesulphonic acid as the catalyst, without any solvent or support. The data are reported and compared with those obtained by other microwave-mediated syntheses or by classical method.
In order to check the possible intervention of non-thermal microwave effects, the best experiment in 'dry media' was carried out with considerable lower yield by conventional heating, in a thermostated oil bath, under the same conditions as under microwaves (time, temperature and vessel).
All the synthesized compounds were tested for their olfactive character and for a potential cosmetic use. The odour evaluation is reported.     

Biologically active peptides: from a laboratory bench curiosity to a functional skin care product

Small, biologically active peptides (short sequences of amino acids) were first described about 40 years ago: TRH, angiotensin, vasopressin, oxytocin, bradykinin. Since then, many more peptides have been isolated from mammalian tissue and organs, and their activity investigated. Essentially, these molecules play a hormonal (messenger) role: released at one point in the body, they act at specific receptor sites at different locations in the organism. Mostly the peptides are transported from the site of release to the site of biological activity through the blood or lymphatic fluid. The use of these molecules in cosmetics does not appear obvious, as the topical application of these highly soluble, fragile and extremely expensive molecules seems inappropriate, and systemic effects (blood transport) are not desired. This paper shows that the obstacles to using highly specific, powerful peptides as 'actives' in cosmetic products can be overcome. Cosmetically interesting activities such as stimulation of collagen synthesis, chemotaxis, anti-stinging effects and others, can be observed and substantiated with chemically modified peptide sequences. Long chain fatty acid conjugates improve skin penetration, specific activity and economic feasibility of these molecules.     

Anti-irritant potential of cosmetic raw materials and formulations

The investigation studied the anti-irritant potential of several substances commonly employed in cosmetic formulations as basic components of the emulsion or as active ingredients, and evaluated the effect of the emulsifier. Five different emulsions were made irritating by addition of croton oil, in sufficient quantity to provoke a clearly adverse reaction in the rabbit, i.e. primary cutaneous irritation index (PII) close to 2. The PII was determined according to the official French methods by applying to symmetrical areas of the back, the irritant base as control and the same base containing the test substance. Fifty-five ingredients were evaluated: gelling agents, plant extracts, molecules defined as healing, anti-inflammatory substances or anaesthesic compounds, etc. The test substances were added to the emulsion at concentrations close to the ones generally found in cosmetics. The qualitative and the quantitative composition of the oil phase was similar for each emulsion.
Several gelling agents, thickeners and polymers which notably reduce skin contact with an irritant, gave good results. Some of the usual healing, anti-inflammatory, local anaesthesic compounds gave the expected results. Some ingredients, though well known, were ineffective. The type of emulsifier, by modifying cutaneous penetration and bio-availability of the active ingredients, may play an important role.
Le potential anti-irritant de constituants de base et compositions cosmétiques     

对典型分选效率公式的分析和评价

对评定分选过程技术效果的几个典型公式进行了全面分析和评价，指出了这些公式的立论基础、推导方法、存在问题、使用价值及应用条件，为正确选用合适的公式提供了理论依据和指导原则。     

Role of proteins in cosmetics

The review critically evaluates the safety and effectiveness of proteins or peptides in cosmetic formulations designed for skin and hair care. Special attention is paid to soluble collagen and the use of this fibrillar protein in combination with detergents.
The authors indicate various misconceptions on the mechanism of the effect of collagen and possible risks if the formulations containing collagen are not used on intact skin. Besides the moisturizing effect of collagen on the stratum corneum, the formation of a protective layer on the surface of the skin or hair, and the formation of complexes with detergents and the mechanisms of the effectiveness of this protein are considered.
Le role des proteines dans les cosmetiques