The three main general styles of art as seen in class. Realism, abstract, and nonobjective. Click on each artist name to go to an outside site and learn more.
This document discusses various chemical reactions that occur in everyday life, including respiration, combustion, burning, explosions caused by dust, reactions with oxygen like rusting metals and food becoming rancid, and hand warmers. It explains the reactants and products of these reactions, as well as factors that can speed up or slow down the reactions. Prevention methods for rust are also outlined, and exothermic and endothermic reactions are defined.
The document discusses Henri Matisse and his cutout artworks that he created in his old age. It explains that when Matisse was 83 years old and sick, he developed a new technique called "drawing with scissors" where he would cut out shapes from painted paper and arrange them to create compositions. The process involved his assistants painting sheets of paper, Matisse cutting out the shapes, and then pasting them onto other sheets of paper. Some of Matisse's most famous cutout works were for a book called "Jazz." The document emphasizes that although Matisse did this work from his bed due to illness, he continued being creative using his memory for ideas until his death.
This document summarizes information about dyes used in daily life. It discusses natural dyes extracted from plants and animals used historically, as well as synthetic dyes produced industrially, such as mauveine. Key requirements for dyes are that they impart permanent color and are colorfast. Theories of color and dye constitution are presented, including chromophores that produce color and auxochromes that intensify color. Specific dyes and their structures and applications are outlined, such as Martius Yellow used for silk, wool and nylon dyeing, indigo used for denim production, and alizarin used for cotton, wool and as a calcium indicator.
This document describes three animal pinch pots made in year 7. The first is a rabbit shaped pinch pot. The second is a bowl with legs. The third is two pinch pots joined together with a pinch pot placed on its side.
This document discusses the classification and properties of various dye classes. It states that different dye classes are only applicable to certain fibre types, and describes the main dye classes for cellulosic fibres (direct, azoic, reactive, vat, sulphur dyes), protein fibres (acid, metal-complex, chrome dyes), other fibres like polyester and acrylic (disperse, cationic dyes). Each dye class is defined in terms of its application method, colour range, fastness properties and main applications. Examples of individual dyes within each class are also provided.
Organic shapes are with a natural look and flowing and curving appearance. These are typically irregular and asymmetrical and are associated with things from the natural world.
Leonardo da Vinci was born in 1452 in Vinci, Italy. He was a true Renaissance man and genius who excelled in multiple fields, including painting, inventing, science, mathematics, writing, music, and botany. As both an artist and engineer, da Vinci created many famous paintings like the Lady with an Ermine and inventions well ahead of his time. He was also unusual in his ability to write with both hands simultaneously in opposite directions.
The three main general styles of art as seen in class. Realism, abstract, and nonobjective. Click on each artist name to go to an outside site and learn more.
This document discusses various chemical reactions that occur in everyday life, including respiration, combustion, burning, explosions caused by dust, reactions with oxygen like rusting metals and food becoming rancid, and hand warmers. It explains the reactants and products of these reactions, as well as factors that can speed up or slow down the reactions. Prevention methods for rust are also outlined, and exothermic and endothermic reactions are defined.
The document discusses Henri Matisse and his cutout artworks that he created in his old age. It explains that when Matisse was 83 years old and sick, he developed a new technique called "drawing with scissors" where he would cut out shapes from painted paper and arrange them to create compositions. The process involved his assistants painting sheets of paper, Matisse cutting out the shapes, and then pasting them onto other sheets of paper. Some of Matisse's most famous cutout works were for a book called "Jazz." The document emphasizes that although Matisse did this work from his bed due to illness, he continued being creative using his memory for ideas until his death.
This document summarizes information about dyes used in daily life. It discusses natural dyes extracted from plants and animals used historically, as well as synthetic dyes produced industrially, such as mauveine. Key requirements for dyes are that they impart permanent color and are colorfast. Theories of color and dye constitution are presented, including chromophores that produce color and auxochromes that intensify color. Specific dyes and their structures and applications are outlined, such as Martius Yellow used for silk, wool and nylon dyeing, indigo used for denim production, and alizarin used for cotton, wool and as a calcium indicator.
This document describes three animal pinch pots made in year 7. The first is a rabbit shaped pinch pot. The second is a bowl with legs. The third is two pinch pots joined together with a pinch pot placed on its side.
This document discusses the classification and properties of various dye classes. It states that different dye classes are only applicable to certain fibre types, and describes the main dye classes for cellulosic fibres (direct, azoic, reactive, vat, sulphur dyes), protein fibres (acid, metal-complex, chrome dyes), other fibres like polyester and acrylic (disperse, cationic dyes). Each dye class is defined in terms of its application method, colour range, fastness properties and main applications. Examples of individual dyes within each class are also provided.
Organic shapes are with a natural look and flowing and curving appearance. These are typically irregular and asymmetrical and are associated with things from the natural world.
Leonardo da Vinci was born in 1452 in Vinci, Italy. He was a true Renaissance man and genius who excelled in multiple fields, including painting, inventing, science, mathematics, writing, music, and botany. As both an artist and engineer, da Vinci created many famous paintings like the Lady with an Ermine and inventions well ahead of his time. He was also unusual in his ability to write with both hands simultaneously in opposite directions.
The document discusses Gee's Bend quilts created by African American women in Gee's Bend, Alabama between 1940-2001. It notes that Gee's Bend remains isolated and the quilts feature unique patterns like stripes, triangles, and housetop designs due to the quilters' limited fabrics. In 2003, the quilters formed the Gee's Bend Quilters Collective to sell and market their quilts.
This document provides information about stained glass windows and a student project to design one. It discusses the history of stained glass in churches from the Gothic period onward. Abbot Suger rebuilt St. Denis church in the early Gothic style and brought in craftsmen to make stained glass windows depicting biblical scenes. For the student project, participants will choose a saint to depict and carefully cut out a design in black construction paper, then fill it in with colored tissue paper to recreate the stained glass effect. Examples of other students' works depicting saints and religious symbols are also shown.
Dyes are colored organic compounds that can impart color to substrates like cloth, paper, plastic or leather. There are several types of dyes classified by their chemistry and application method. Reactive dyes are widely used for cotton dyeing due to their high washfast properties. Disperse dyes are used predominantly on polyester fibers. Direct dyes are water-soluble and used for cotton and cellulose. Vat dyes are applied to cellulosic fibers from a soluble leuco form. Sulfur dyes provide good washfastness for economical cotton dyeing.
This document discusses the fundamentals of color, including:
1. Color is perceived when light wavelengths are absorbed, reflected, refracted, scattered, or diffracted by matter. It is a psychological response to a physical stimulus.
2. Color mixing can be additive, involving light sources, or subtractive, involving dyes and pigments. Subtractive color mixing uses cyan, magenta, and yellow primaries.
3. Color perception involves light stimulation of red, green, and blue cone receptors in the eye, which signals are interpreted by the brain.
Vincent van Gogh's Starry Night was painted in 1889. It depicts a night sky filled with swirling clouds and stars over a small village. While the sky is dramatic, the village below appears peaceful. The cypress tree and church steeple are painted with curving lines that guide the eye across the canvas. Van Gogh used vivid colors, especially yellow and blue, not for realism but to convey emotion. The bright stars and moon contrast with the darker village to symbolize hope and the possibility of finding light even in the darkness.
Article on history, evolution, types, production and uses of various industrial inks, dyes, pigments, colors and there usage in various other applications
Giorgio de Chirico was an Italian artist who founded the Metaphysical Art Movement in the early 20th century. He had a profound influence on Surrealism with his enigmatic works that created "images of forlornness and emptiness" using motifs like empty arcades, towers, and elongated shadows. De Chirico believed that for a work of art to be truly immortal, it must break from logic and common sense and enter a realm of childhood visions and dreams. His style emphasized the hidden meanings of ordinary objects and places in a neoclassical or neo-baroque style. Famous works include The Disquieting Muses, Enigma of an Autumn Afternoon, and
This document discusses the role of chemistry in everyday life through numerous examples. It begins by introducing chemistry in toothpaste, noting the main ingredients of fluoride and abrasives. It then discusses the chemistry of raising agents in bread, caffeine in coffee, sulfur compounds in onions, nicotine and other chemicals in cigarettes, ethanol in alcoholic drinks, elemental composition of the human body, neurochemicals involved in emotions, photosynthesis in food production, soap chemistry, why ice floats, food preservatives, enzymes in digestion, sunscreen chemicals, rust formation chemistry, and ingredients in cosmetics. The document aims to illustrate how chemistry underlies many everyday products and biological processes.
Abstract Expressionism was an influential art movement from the 1940s-1950s known for spontaneous, expressive styles. It encompassed action painting and color field painting. Key artists included Jackson Pollock, Willem de Kooning, and Mark Rothko. Op Art from the 1950s-1970s used optical illusions to create the illusion of movement through geometric shapes and lines. Pop Art emerged in the late 1950s-1960s as a reflection of consumer culture, using images from popular culture and advertising. Andy Warhol and Roy Lichtenstein were influential Pop artists. Minimalism of the 1960s-1970s stripped art to basic geometric forms and materials to remove expression. Key minimalist artists were Richard Serra,
The document provides an overview of the history and evolution of tattoo art. It discusses how the earliest tattoos originated in places like Polynesia, Egypt, and among Native American tribes for therapeutic or symbolic purposes. Over time, tattoos became associated with sailors, criminals, and circus performers. Tattooing grew in popularity in the 1960s as part of hippie culture and stigma was reduced. Today, tattooing is more mainstream and popular than ever due to TV shows and celebrities with tattoos. The document also outlines various tattoo styles including tribal, Asian-inspired, and old school designs as well as covers topics like tattoo fillers, dangers, and modern practices.
Ceramics are made from primary or secondary clay. Primary clay is formed from decomposing rock, while secondary clay is transported by water, air or ice. Earthenware is made from secondary clay and hardens at low temperatures but remains porous. Before making ceramics, clay must be wedged and kneaded to remove air bubbles and distribute water evenly to prevent explosions during firing. Clay goes through stages such as leather hard and bone dry during drying and is shaped using techniques like coil building and working with slabs. Tools are used to shape and model clay, then pieces are fired in kilns, with cones used to monitor heat levels during firing. Glazes can be applied after bisque firing to
El documento describe cómo el soporte de una obra puede influir en su organización y composición de varias maneras. El soporte puede ser circular, ovalado, semicircular u otras formas no convencionales como una capilla. La forma del soporte afecta la lectura de la obra y un artista puede combinar diferentes formatos en una sola pieza.
This document discusses various types of dyes used for different textile fibers, including their classification, application methods, and suitability. It covers direct dyes for cellulosic fibers, azoic dyes which form insoluble colors within fibers, vat dyes which require chemical treatment, sulphur dyes for dark shades, and reactive and acid dyes for protein fibers like wool and silk. Each dye class has different properties in terms of color range, fastness, ease of use, and fiber compatibility. The appropriate dye must be selected based on the fiber and desired color and performance characteristics.
The document discusses the history and constituents of soaps and detergents. It notes that soap making dates back to 1500 BC and involved combining plant/animal oils with alkaline salts. Modern synthetic detergents slowly replaced soaps and were first used for dishwashing and laundering fine fabrics. Soaps are made through saponification which involves heating oils/fats with lye, while detergents are made from petrochemicals. Both soaps and detergents work by forming micelles that emulsify oils and allow them to be rinsed away. While soaps are more eco-friendly, detergents work better in hard water. However, detergents pose health and environmental risks if certain regulations are
Chemistry is present in everyday life through foods, air, cleaning products, emotions, and all objects. Some common examples of chemistry include water, table salt, nail polish remover, table sugar, battery acid, and vinegar. Many chemical reactions also occur in daily life through photosynthesis, cellular respiration, rusting of iron, digestion, combustion, soap cleaning, baking soda and vinegar reactions, carbonation, acid rain, ant bites, fruit ripening, and flowers. Chemistry plays a vital role in providing necessities like food, medicine, fuels, and materials through various chemical processes and compounds.
Judy Chicago is an American feminist artist born in 1939 who pioneered feminist art. In 1971 she co-founded the Feminist Art Program at CalArts. Her most famous work is The Dinner Party, a massive installation completed in 1979 paying tribute to important women throughout history through place settings arranged on a triangular table. It features elaborate ceramic plates and needlework challenging patriarchal norms and drawing attention to women's historical contributions.
A Comparative Study on Dyeing of Cotton and Silk Fabric Using Madder as a Nat...IOSR Journals
This document presents a study comparing the dyeing of cotton and silk fabrics with madder, a natural red dye. Various mordanting techniques were tested, including pre-mordanting, post-mordanting, and simultaneous mordanting with alum and copper sulfate. The dyed fabrics were evaluated based on color characteristics and colorfastness properties. The results showed that silk fabrics dyed darker shades than cotton and exhibited better colorfastness to washing and rubbing when mordanted. Mordanted silk samples showed deeper colors and greater wash fastness compared to mordanted cotton samples. While mordanting improved some properties, the dyed fabrics generally displayed poor perspiration fastness.
Banksy is a famous anonymous street artist believed to have been born in Bristol, England in 1974. He began his career in the early 1990s as part of Bristol's graffiti scene and developed his signature stenciling style. By the 2000s, Banksy had gained international recognition for his politically and socially charged street art addressing topics like war, inequality, and capitalism. His art combines striking images with slogans and utilizes various subjects to communicate his messages across boundaries.
Bill Viola is an American video artist born in 1951. He graduated from Syracuse University with a Bachelor of Fine Arts in 1973. In the 1970s, he worked as a video technician and studied with composer David Tudor. He traveled extensively, including to Indonesia and Japan. Viola's video art focuses on themes of human consciousness, experience, birth, death, love, and emotion. His works often have a meditative, transcendental quality and make use of slow motion to immerse viewers. Viola has exhibited widely and is considered a major contemporary artist.
Sunday Evening lesson at MoM Summer School.
Inspired by EXPOneer project www.EXPOneer.de the presentation offers suggestions on how to set up a flexible easy to design and mount exhibition at school.everything reusable . EXPOneer offers also the free template and now we share ours
The document discusses Gee's Bend quilts created by African American women in Gee's Bend, Alabama between 1940-2001. It notes that Gee's Bend remains isolated and the quilts feature unique patterns like stripes, triangles, and housetop designs due to the quilters' limited fabrics. In 2003, the quilters formed the Gee's Bend Quilters Collective to sell and market their quilts.
This document provides information about stained glass windows and a student project to design one. It discusses the history of stained glass in churches from the Gothic period onward. Abbot Suger rebuilt St. Denis church in the early Gothic style and brought in craftsmen to make stained glass windows depicting biblical scenes. For the student project, participants will choose a saint to depict and carefully cut out a design in black construction paper, then fill it in with colored tissue paper to recreate the stained glass effect. Examples of other students' works depicting saints and religious symbols are also shown.
Dyes are colored organic compounds that can impart color to substrates like cloth, paper, plastic or leather. There are several types of dyes classified by their chemistry and application method. Reactive dyes are widely used for cotton dyeing due to their high washfast properties. Disperse dyes are used predominantly on polyester fibers. Direct dyes are water-soluble and used for cotton and cellulose. Vat dyes are applied to cellulosic fibers from a soluble leuco form. Sulfur dyes provide good washfastness for economical cotton dyeing.
This document discusses the fundamentals of color, including:
1. Color is perceived when light wavelengths are absorbed, reflected, refracted, scattered, or diffracted by matter. It is a psychological response to a physical stimulus.
2. Color mixing can be additive, involving light sources, or subtractive, involving dyes and pigments. Subtractive color mixing uses cyan, magenta, and yellow primaries.
3. Color perception involves light stimulation of red, green, and blue cone receptors in the eye, which signals are interpreted by the brain.
Vincent van Gogh's Starry Night was painted in 1889. It depicts a night sky filled with swirling clouds and stars over a small village. While the sky is dramatic, the village below appears peaceful. The cypress tree and church steeple are painted with curving lines that guide the eye across the canvas. Van Gogh used vivid colors, especially yellow and blue, not for realism but to convey emotion. The bright stars and moon contrast with the darker village to symbolize hope and the possibility of finding light even in the darkness.
Article on history, evolution, types, production and uses of various industrial inks, dyes, pigments, colors and there usage in various other applications
Giorgio de Chirico was an Italian artist who founded the Metaphysical Art Movement in the early 20th century. He had a profound influence on Surrealism with his enigmatic works that created "images of forlornness and emptiness" using motifs like empty arcades, towers, and elongated shadows. De Chirico believed that for a work of art to be truly immortal, it must break from logic and common sense and enter a realm of childhood visions and dreams. His style emphasized the hidden meanings of ordinary objects and places in a neoclassical or neo-baroque style. Famous works include The Disquieting Muses, Enigma of an Autumn Afternoon, and
This document discusses the role of chemistry in everyday life through numerous examples. It begins by introducing chemistry in toothpaste, noting the main ingredients of fluoride and abrasives. It then discusses the chemistry of raising agents in bread, caffeine in coffee, sulfur compounds in onions, nicotine and other chemicals in cigarettes, ethanol in alcoholic drinks, elemental composition of the human body, neurochemicals involved in emotions, photosynthesis in food production, soap chemistry, why ice floats, food preservatives, enzymes in digestion, sunscreen chemicals, rust formation chemistry, and ingredients in cosmetics. The document aims to illustrate how chemistry underlies many everyday products and biological processes.
Abstract Expressionism was an influential art movement from the 1940s-1950s known for spontaneous, expressive styles. It encompassed action painting and color field painting. Key artists included Jackson Pollock, Willem de Kooning, and Mark Rothko. Op Art from the 1950s-1970s used optical illusions to create the illusion of movement through geometric shapes and lines. Pop Art emerged in the late 1950s-1960s as a reflection of consumer culture, using images from popular culture and advertising. Andy Warhol and Roy Lichtenstein were influential Pop artists. Minimalism of the 1960s-1970s stripped art to basic geometric forms and materials to remove expression. Key minimalist artists were Richard Serra,
The document provides an overview of the history and evolution of tattoo art. It discusses how the earliest tattoos originated in places like Polynesia, Egypt, and among Native American tribes for therapeutic or symbolic purposes. Over time, tattoos became associated with sailors, criminals, and circus performers. Tattooing grew in popularity in the 1960s as part of hippie culture and stigma was reduced. Today, tattooing is more mainstream and popular than ever due to TV shows and celebrities with tattoos. The document also outlines various tattoo styles including tribal, Asian-inspired, and old school designs as well as covers topics like tattoo fillers, dangers, and modern practices.
Ceramics are made from primary or secondary clay. Primary clay is formed from decomposing rock, while secondary clay is transported by water, air or ice. Earthenware is made from secondary clay and hardens at low temperatures but remains porous. Before making ceramics, clay must be wedged and kneaded to remove air bubbles and distribute water evenly to prevent explosions during firing. Clay goes through stages such as leather hard and bone dry during drying and is shaped using techniques like coil building and working with slabs. Tools are used to shape and model clay, then pieces are fired in kilns, with cones used to monitor heat levels during firing. Glazes can be applied after bisque firing to
El documento describe cómo el soporte de una obra puede influir en su organización y composición de varias maneras. El soporte puede ser circular, ovalado, semicircular u otras formas no convencionales como una capilla. La forma del soporte afecta la lectura de la obra y un artista puede combinar diferentes formatos en una sola pieza.
This document discusses various types of dyes used for different textile fibers, including their classification, application methods, and suitability. It covers direct dyes for cellulosic fibers, azoic dyes which form insoluble colors within fibers, vat dyes which require chemical treatment, sulphur dyes for dark shades, and reactive and acid dyes for protein fibers like wool and silk. Each dye class has different properties in terms of color range, fastness, ease of use, and fiber compatibility. The appropriate dye must be selected based on the fiber and desired color and performance characteristics.
The document discusses the history and constituents of soaps and detergents. It notes that soap making dates back to 1500 BC and involved combining plant/animal oils with alkaline salts. Modern synthetic detergents slowly replaced soaps and were first used for dishwashing and laundering fine fabrics. Soaps are made through saponification which involves heating oils/fats with lye, while detergents are made from petrochemicals. Both soaps and detergents work by forming micelles that emulsify oils and allow them to be rinsed away. While soaps are more eco-friendly, detergents work better in hard water. However, detergents pose health and environmental risks if certain regulations are
Chemistry is present in everyday life through foods, air, cleaning products, emotions, and all objects. Some common examples of chemistry include water, table salt, nail polish remover, table sugar, battery acid, and vinegar. Many chemical reactions also occur in daily life through photosynthesis, cellular respiration, rusting of iron, digestion, combustion, soap cleaning, baking soda and vinegar reactions, carbonation, acid rain, ant bites, fruit ripening, and flowers. Chemistry plays a vital role in providing necessities like food, medicine, fuels, and materials through various chemical processes and compounds.
Judy Chicago is an American feminist artist born in 1939 who pioneered feminist art. In 1971 she co-founded the Feminist Art Program at CalArts. Her most famous work is The Dinner Party, a massive installation completed in 1979 paying tribute to important women throughout history through place settings arranged on a triangular table. It features elaborate ceramic plates and needlework challenging patriarchal norms and drawing attention to women's historical contributions.
A Comparative Study on Dyeing of Cotton and Silk Fabric Using Madder as a Nat...IOSR Journals
This document presents a study comparing the dyeing of cotton and silk fabrics with madder, a natural red dye. Various mordanting techniques were tested, including pre-mordanting, post-mordanting, and simultaneous mordanting with alum and copper sulfate. The dyed fabrics were evaluated based on color characteristics and colorfastness properties. The results showed that silk fabrics dyed darker shades than cotton and exhibited better colorfastness to washing and rubbing when mordanted. Mordanted silk samples showed deeper colors and greater wash fastness compared to mordanted cotton samples. While mordanting improved some properties, the dyed fabrics generally displayed poor perspiration fastness.
Banksy is a famous anonymous street artist believed to have been born in Bristol, England in 1974. He began his career in the early 1990s as part of Bristol's graffiti scene and developed his signature stenciling style. By the 2000s, Banksy had gained international recognition for his politically and socially charged street art addressing topics like war, inequality, and capitalism. His art combines striking images with slogans and utilizes various subjects to communicate his messages across boundaries.
Bill Viola is an American video artist born in 1951. He graduated from Syracuse University with a Bachelor of Fine Arts in 1973. In the 1970s, he worked as a video technician and studied with composer David Tudor. He traveled extensively, including to Indonesia and Japan. Viola's video art focuses on themes of human consciousness, experience, birth, death, love, and emotion. His works often have a meditative, transcendental quality and make use of slow motion to immerse viewers. Viola has exhibited widely and is considered a major contemporary artist.
Sunday Evening lesson at MoM Summer School.
Inspired by EXPOneer project www.EXPOneer.de the presentation offers suggestions on how to set up a flexible easy to design and mount exhibition at school.everything reusable . EXPOneer offers also the free template and now we share ours
Face creams come in a variety of types to suit different skin needs, such as regeneration creams for aging skin, emollient creams for moisturizing, and mattifying creams for oily skin. They are essential for nourishing and keeping skin of all ages looking healthy. Face creams are classified based on skin type, such as dry, normal and combination, to provide the appropriate treatment for each skin's specific needs.
Hair colouring involves adding colour to natural hair to disguise grey hair or change its colour. There are three main types of hair colour: temporary colour washes out after one wash but is found in sprays and gels; semi-permanent colour lasts 6-8 washes as it slightly opens hair cuticles to allow some colour molecules in; and permanent colour uses hydrogen peroxide to activate colour molecules to form large coloured molecules trapped in the hair cortex, giving colour that lasts until new hair growth occurs.
1. La chimica in salotto
Lavoro realizzato da:
Camilla Z. Christian M. Elif A. e Malina S.
Pubblicato in occasione del Carnevale della Chimica del mese di ottobre 2011 sul blog www.scienceforpassion.com
2. La chimica in salotto
Chi l’avrebbe mai immaginato che
eravamo circondati da così tanti oggetti
che hanno a che fare con la chimica?
3. Promemoria:
cosa studia la chimica?
La chimica studia la composizione, la
struttura e le proprietà della materia. La
parola “materia indica tutto ciò che ci
materia”
materia
circonda e che è caratterizzato da una massa
e da un volume.
4. Il salotto è un luogo in cui tutta la famiglia si
riunisce a guardare film, giocare a giochi di
società e tante altre cose.
Il nostro gruppo ha deciso di parlare degli
oggetti che comunemente troviamo dentro il
salotto; molti di essi hanno all’interno
salotto all’
sostanze chimiche In particolare, abbiamo
chimiche.
deciso di approfondire la chimica nascosta
dentro: le lampadine la televisione e i CD.
lampadine,
5. La chimica dentro
una lampadina …
La lampadina è un dispositivo elettrico
specificamente progettato per produrre luce; a
questo scopo può utilizzare differenti tecnologie!
7. Il vetro di una comune lampadina a
incandescenza non è molto più spesso di un
normale foglio di carta.
I bulbi vengono modellati partendo da un nastro
di vetro fuso, che viene soffiato in appositi
stampi che hanno la forma della lampadina.
La parte più importante è il filamento: è una
piccola molla costituita da tungsteno, un
metallo estremamente resistente alle alte
temperature.
8. Il piccolo filamento, quando viene
attraversato dall’energia elettrica, diventa
incandescente fino a illuminarsi.
Quasi la totalità dell’energia è perduta sotto
forma di calore, mentre quella che resta serve
a produrre la luce.
Il filamento di tungsteno è alloggiato su un fusto
di vetro, percorso al suo interno da due fili di
metallo, che portano l’energia elettrica.
Il bulbo della lampadina viene poi riempito
con un gas, generalmente una miscela di argon
e azoto, che rallenta il consumo del filamento
dovuto al calore.
10. Le lampadine a risparmio energetico stanno
sostituendo le lampadine ad incandescenza.
Quelle che si utilizzano in casa si chiamano
lampadine fluorescenti compatte ed hanno
spesso una forma a spirale.
Sono formate da un tubo di vetro, al cui interno
è stato messo un gas e anche una piccola
quantità di mercurio. La superficie interna del
tubo è rivestita di un materiale fluorescente.
Ai due estremi del tubo sono presenti due
elettrodi.
11. Quando accendiamo la luce, gli elettroni in
movimento tra i due elettrodi “convincono” gli
atomi di mercurio a emettere radiazione
ultravioletta.
ll materiale fluorescente di cui è ricoperto il
tubo, colpito da queste radiazioni, emette a
sua volta luce visibile.
Le lampadine a risparmio energetico
consumano molto meno di una lampadina a
incandescenza e si può risparmiare fino all'80%.
12. ATTENZIONE!
Quando si rompono, non possono essere
buttate nella spazzatura! Vanno portate in
appositi punti per il riciclaggio.
Se una lampadina fluorescente compatta si
rompe e il contenuto fuoriesce, bisogna aerare
bene la stanza e poi pulire con uno straccio
bagnato. È meglio evitare che la pelle venga a
contatto coi frammenti, e non bisogna usare
l'aspirapolvere.
14. Un televisore è un mondo di materiali, che sia di
tipo classico, al plasma o a cristalli liquidi: vetro,
metalli, materie plastiche, materiali luminescenti.
Noi vorremmo concentrarci sul tipo di monitor:
cosa vuol dire monitor a cristalli liquidi? E al
plasma?
15. Il funzionamento di uno schermo al plasma si
basa sulla fluorescenza, cioè sull’emissione
della luce da parte di sostanze chiamate fosfori.
Ci sono moltissime piccole celle, posizionate in
mezzo a due pannelli di vetro. Queste servono a
mantenere all’interno un miscuglio di gas (neon
e xeno).
Il gas nelle celle viene elettricamente
trasformato in un plasma che “convince” i
fosfori ad emettere luce.
16. Il funzionamento di uno schermo a cristalli liquidi
si basa, invece, sulle proprietà di particolari
sostanze chiamate appunto cristalli liquidi.
I cristalli liquidi, in particolari condizioni, presentano
caratteristiche sia dello stato liquido che di quello
solido. Per questo motivo si chiamano così!
I cristalli liquidi sono intrappolati fra due
superfici di vetro provviste di numerosi contatti
elettrici. Attraverso questi contatti si può applicare
corrente ai cristalli liquidi: la corrente condiziona il
comportamento della luce che passa nel televisore
e ci permette di vedere le immagini!
18. La sigla CD significa Compact Disc… In
Disc…
questo semplice oggetto è racchiusa un
sacco di chimica!
Infatti, è composto da un disco di
policarbonato trasparente generalmente di
trasparente,
12 cm di diametro. Nella parte centrale
troviamo un sottile foglio di materiale
metallico sul quale vengono memorizzale
informazioni. Tali informazioni
successivamente vengono lette per mezzo
di un laser.
19. Questa è la nostra chimica
in salotto: non avremmo
mai immaginato che in una
lampadina, una televisione
o un CD ci fossero tante
sostanze chimiche “al
lavoro”!