Middle note

Adsorbates may form ordered overlayers, which can have their own periodicity. The adsorbate structure is given with respect to that of the substrate metal. For simple arrangements the Wood notation is used some examples are given in Fig. A.3. The notation Pt (110) - c(2x2) O means that oxygen atoms form an ordered overlayer with a unit cell that has twice the dimensions of the Pt (110) unit cell, and an additional O in the middle. Note that this abbreviation does not specify where the O is with respect to the Pt atoms. It may be on top of the Pt atoms but also in bridged or fourfold sites, or in principle anywhere as long as the periodic... 

Since fragrance materials differ in volatility, the odor of a perfume composition changes during evaporation and is divided into the top note, the middle notes or body, and the end note or dry out, which consists mainly of less volatile compounds. Odor perception also depends largely on odor intensity. Therefore, the typical note is not determined only by the most volatile compounds. 

Perfumery materials differ widely in their volatility, from those that last only a few minutes on a smelling strip to those that are still there after several weeks. It is usual therefore (Poucher 1955 Carles 1961) to divide materials into three groups the base notes which are the most long lasting the middle notes, or modifiers, which are of medium volatility and the top notes which are the most volatile. The balance between these three groups of materials in a formula is of great importance to the way in which the perfume diffuses during its evaporation and to its aesthetic quality. 

Apart from the materials already mentioned the top note contains a simple mixture of bergamot and orange. The middle note is dominated by a traditional jasmin base, with muguet (hydroxycitronellal 10%), and rose. At the heart of the perfume is the classical chypre accord between vetiveryl acetate (10%), methyl ionone, oakmoss, aldehyde C14, coumarin, sandalwood, patchouli, musk ketone, and amber. The amber note can be reproduced by the simple but effective combination of labdanum, olibanum, and vanilla. Small amounts of other animalic notes such as civet may also be used. 

Produced by steam distillation from the black peppercorns, the essential oil is water-white to pale olive in colour, with a warm, spicy (peppery), fresh aroma. It has a middle note and blends well with rose, rosemary, marjoram, frankincense, olibanum, sandalwood and lavender however, it should be used in small amounts only (Borges et al., 2003). 

Middle note A fragrance note of intermediate volatility and lasting power. 

Note A classification of aromatic components of essential oils and perfumes. Top notes are sharp, penetrating and highly volatile (e.g. citrus oils, peppermint). Middle note characteristics are used to give body to blends (e.g. geranium, lavender). Base notes are the least volatile and used as fixatives to give more permanence (e.g. sandalwood, vetivert). 

The Middle Notes are based on reaction flavourings to impart specific complex roasted, meaty and smoky notes roasted chicken, boiled beef, smoked ham. They improve the overall taste with a general meaty background and a good mouthfeeling. Meaty middle notes are often based on the reaction of vitamin Bl, cystein and reducing sugars. Fat included in the reaction modifies the product into a specific animal direction chicken, beef, mutton, pork. 

The process to produce reaction flavourings is not just simple therefore the variability of the middle notes is also limited for economic reasons. 

Complex flavour, specific to a particular dish Analogue to middle-note (body) of a savoury flavour Brings out the personality of a particular dish... 

Middle Notes Aroma and taste. Specific notes obtained by process flavours (heating proteins, carbohydrates, lipids, etc.) Proteins meat, meat extracts, poultry, eggs, dairy products, fish, fish extracts, yeast... 

Perfumes are usually mixtures of notes, fragrances with similar aromas but different volatilities (the ease with which a substemce is converted into a gas). The most volatile is called the top note. It s what you initially smell. The middle note is the most noticeable smell, while the end note fragrances are responsible for the lingering odor of the perfume. Figure 17-5 shows the chemical structure of several of the fragrances commonly used in perfumes. 

The top note is the first smeU one encormters when opening a bottle of perfume. The smells in the top note are caused by the more volatile molecules that quickly work their way out of the bottle and into the air, where they are detected by sensors in the nose. The middle note is detected only after a short time, and these molecules are usually larger and less volatile than those in the top note. The middle-note molecules tend to persist on the skin. Finally, the end note usually contains more animal or earthy fragrances. It is composed of large molecules that evaporate slowly (less volatility). Hiese compounds in the end note also help hold the more volatile notes in place, preventing them from vaporizing too quickly. 

Middle notes After top note evaporation the components contributing to the main body... 

Back notes After top and middle note evaporation, the less volatile pressure components... 

Middle note heart note), which contains the main... 

Perfumes are mixtures of molecules, generally with molecular mass below 300, of varying volatilities. Their top note is made of volatile substances with instant impact. Once this disappears, the middle note is longer lived, while the base note which may linger for days or weeks, and may make up 50% of the perfume, are deep odors that may not be smelt for some time. The fixative is a molecule with a deep odor that has a low volatility and which helps to reduce evaporation of the more... 

Fig. 10,30 A typical molecular orbital energy level diagram for Period 2 homonuclear diatomic molecules. The valence atomic orbitals are drawn in the columns on the left and the right the molecular orbitals are shown in the middle. Note that the k orbitals form doubly degenerate pairs. The sloping lines joining the molecular orbitals to the atomic orbitals show the principal composition of the molecular orbitals. This diagram is suitable for O2 and F2 the configuration of O2 is shown.

For the generalized displacements for each element in the finite element model, nine generalised displacements are at each end of the element, while two displacements associated with y and z axes are at the middle note of each element. The generalized displacements are depicted in Figure 1. 

---