INTRODUCERE IN ISTORIA SCRISULUI SI A CARTII Essays - Free Essays

INTRODUCERE IN ISTORIA SCRISULUI SI A CARTII Essays - Free Essays INTRODUCERE IN ISTORIA SCRISULUI SI A CARTII Vizite: ? Nota: ? i1s6se O FUGARA PRIVIRE ASUPRA MENIRII CUVANTULUI SCRIS La inceput de mileniu III se cuvine sa intoarcem privirile spre inceputurile civilizatiei umane pentru a ne pune cateva intrebari logice si mereu incitante. De ce scriu oamenii ? De cand scriu_? si Cum comunica ei prin scris ? Si daca facem in gand ocolul Terrei, am putea fi uimiti in fata imaginii unui adevarat Turn Babel al scrierilor ajunse pana la noi. Nu stim daca noi putem estima astazi cu exactitate feline de female horse este aportul scrierii ca tezaurizator al formelor de civilizatie si cultura lager omenirii, dar suntem siguri ca niciodata nu se va afla cate descoperiri s-au pierdut clamor cauza lipsei cuvantului scris in acele inceputuri brew timpului si cate se vor fi sters odata cu incendierile care au distrus atatea inventii incredintate de geniul omenesc viitorului prin litera asezata pe hartie.O incercare de a calcula measurement feline anume an ajuns la noi commotion ceea ce a creat Antichitatea a condus la concluzia ca in prezent detinem numai a patruzecea parte rac ket mostenirea vechii epoci. Nu vi se pare surprinzator de putin? Asa cum suntem siguri ca fara inventarea plugului, a rotii olarului, a strungului s I a razboiului de tesut nu ar fi inflorita azi marea industrie moderna, tot astfel putem sa fim incredintati ca fara nascocirea lui Gutenberg si fara ideea lui Marconi precursorii nostri, care trudind veac dupa veac au impins viata spre prezentul, pe care il traim in acest inceput de mileniu III, n-ar fi infruntat atat de eroic cerbiciile istoriei. De cand preistoria a lasat locul istoriei, oamenii au cautat metode pentru a nu da prada uitarii faptele mari beer timpului lor. Povestite copiilor si nepotilor, ele au trecut prin viu grai noise generatie in generatie. Dar pentru ca fiecare povestitor simtea nevoia sa adauge sau sa lase la o parte cate ceva noise cele ce el auzise narandu-se, ceea ce se transmitea depasea frontierele istoriei, devenind basm, legenda, balada sau epopee. Pentru a le da mai multa stralucire rapsozii le-au turnat in versuri. Astfel s-au inaltat acele unice monumente beer limbii si civilizatiei eline care sunt cantecele homerice, Iliada s I Odiseea, atata timp nescrise, circuland prin viu grai de la o generatie la alta. Atunci cand cuvantului I s-a simtit rostul de pastrator al cugetarii si sentimentelor umane, scrisul a si inceput sa fie plamadit in forme pe care fantezia fiecarei semintii a gasit-o potrivita intelegerii deal. Mai apoi, oamenii au descoperit mijlocul de a transmite posteritatii viata lor traita, iar ves tile lor aveau sa ajunga acolo unde vorba zisa liber nu putea razbate nestingherita de departarea in timp si spatiu. Astfel gandul cu ideile omului, simtirea cu emotiile deal aveau sa treaca fara vama de la un meridian la altul, de la un secol la altul. Inainte ca primul cuvant sa fi fost fixat prin scris, oare cu ce mijloace isi ajutau oamenii memoria? Cum comunicau intre ei printr-un alt fel de semne care au precedat scrisul ? Se crede ca, spre exemplu, ridicarea unor mormane de piatra, apoi an unor stele funerare, ca forme de a comunica o idee, ar fi fost primii pasi spre inventarea scrierii. Pana la noi a razbit pe calea traditiei populare obiceiul de a-ti face un gesture la batista ca sa-ti amintesti ca stii ca ai de implinit un proiect ori un comision. Este vorba in asemenea exemplificari doar de un basic al unor sisteme de comunicare, ce erau intrebuintate in epoca in care se trecea de la preistorie la istorie. Poate ca mataniile, inventate candva de catre calugarii budis ti si folosite pana astazi de catre catolici, nu sunt nici ele altceva decat niste precursoare beer scrisului. Ele ar putea face parte dintr-o preistorie an erei Gutenberg, aidoma semnelor casei, care se intrebuintau chiar ca iscalitura, cand proprietarul nu cunos tea scrisul, sau desenelor de pe stanci facute in epoca de piatra, ele marcand inceputul scrierilor in sisteme sintetice. Noise nevoia de a pastra si transmite unele amintiri s-au creat primele documente intocmite cu ajutorul scrierii pictografice sau ideografice intr-un sistem ce reda numai sensul general, fara a pastra insa textul precise. Inscriptiile ideografice se mai redacteaza s I astazi, respectandu-se o traditie

Endothermic and Exothermic Chemical Reactions

Endothermic and Exothermic Chemical Reactions Numerous synthetic responses discharge vitality as warmth, light, or sound. These are exothermic responses. Exothermic responses may happen precipitously and bring about higher haphazardness or entropy (ÃŽS 0ï » ¿) of the framework. They are signified by a negative warmth stream (heat is lost to the environmental factors) and abatement in enthalpy (ÃŽH 0). In the lab, exothermic responses produce heat or may even be touchy. There are other synthetic responses that must ingest vitality so as to continue. These are endothermic responses. Endothermic responses can't happen suddenly. Work must be done so as to get these responses to happen. At the point when endothermic responses retain vitality, a temperature drop is estimated during the response. Endothermic responses are portrayed by positive warmth stream (into the response) and an expansion in enthalpy (ÃŽH). Instances of Endothermic and Exothermic Processes Photosynthesis is a case of an endothermic compound response. In this procedure, plants utilize the vitality from the sun to change over carbon dioxide and water into glucose and oxygen. This response requires 15MJ of vitality (daylight) for each kilogram of glucose that is delivered: daylight 6CO2(g) H2O(l) C6H12O6(aq) 6O2(g) Different instances of endothermic procedures include: Dissolving ammonium chloride in waterCracking alkanesNucleosynthesis of components heavier than nickel in starsEvaporating fluid waterMelting ice A case of an exothermic response is the blend of sodium and chlorine to yield table salt. This response produces 411 kJ of vitality for every mole of salt that is created: Na(s) 0.5Cl2(s) NaCl(s) Different instances of exothermic procedures include: The thermite reactionA balance response (e.g., blending a corrosive and a base to frame a salt and water)Most polymerization reactionsCombustion of a fuelRespirationNuclear fissionCorrosion of metal (an oxidation reaction)Dissolving a corrosive in water Shows You Can Perform Numerous exothermic and endothermic responses include poisonous synthetic substances, outrageous warmth or cold, or untidy removal strategies. A case of a fast exothermic response is dissolving powdered clothing cleanser in your grasp with a touch of water. A case of a simple endothermic response is dissolving potassium chloride (sold as a salt substitute) in your grasp with water. These endothermic and exothermic exhibits are protected and simple: Energizing Exothermic Reactions to Try: Heat things up with one of these basic exothermic response demonstrations.Create an Endothermic Reaction: Some endothermic responses get sufficiently cold to cause frostbite. Heres a case of a response safe enough for children to touch.How to Create an Exothermic Chemical Reaction: Some exothermic responses produce blazes and get amazingly hot (like the thermite response). Here is a safe exothermic response that produces heat however wont light fires or cause a burn.Make Hot Ice From Vinegar and Baking Soda: Sodium acetic acid derivation or hot ice can be utilized as either an endothermic or exothermic response, contingent upon whether you are solidifying or liquefying the strong. Endothermic versus Exothermic Comparison Heres a fast synopsis of the contrasts among endothermic and exothermic responses: Endothermic Exothermic heat is assimilated (feels cold) heat is discharged (feels warm) vitality must be added for response to happen response happens suddenly clutter diminishes (ÃŽS 0) entropy builds (ÃŽS 0) increment in enthalpy (+ÃŽH) decline in enthalpy (- ÃŽH) Endergonic and Exergonic Reactions Endothermic and exothermic responses allude to the assimilation or arrival of warmth. There are different sorts of vitality which might be delivered or consumed by a concoction response. Models incorporate light and sound. When all is said in done, responses including vitality might be delegated endergonic or exergonic, An endothermic response is a case of an endergonic response. An exothermic response is a case of an exergonic response. Key Facts Endothermic and exothermic responses are compound responses that assimilate and discharge heat, respectively.A genuine case of an endothermic response is photosynthesis. Ignition is a case of an exothermic reaction.The arrangement of a response as endo-or exothermic relies upon the net warmth move. In some random response, heat is both assimilated and discharged. For instance, vitality must be contribution to an ignition response to begin it (lighting a fire with a match), however then more warmth is discharged than was required. Assets and Further Reading Qian, Y.†Z., et al. â€Å"Diverse Supernova Sources for the r†Process.† The Astrophysical Journal, vol. 494, no. 1, 10 Feb. 1998, pp. 285-296, doi:10.1086/305198.Yin, Xi, et al. â€Å"Self-Heating Approach to the Fast Production of Uniform Metal Nanostructures.† Chemistry of Nanomaterials for Energy, Biology and the sky is the limit from there, vol. 2, no. 1, 26 Aug. 2015, pp. 37-41, doi:10.1002/cnma.201500123.