(function () {
function textOf(el) {
return (el && el.textContent || "").replace(/\s+/g, " ").trim();
}
function resolveItemUrl() {
var match = window.location.search.match(/[?&]item=(\d+)/);
if (!match) {
return null;
}
return window.location.origin + "/a-" + match[1] + "/";
}
function loadAccordion() {
var url = resolveItemUrl();
if (!url) {
return Promise.resolve(null);
}
return new Promise(function (resolve, reject) {
var xhr = new XMLHttpRequest();
xhr.open("GET", url, true);
xhr.onload = function () {
if (xhr.status < 200 || xhr.status >= 400) {
reject(new Error("item page " + xhr.status));
return;
}
var doc = new DOMParser().parseFromString(xhr.responseText, "text/html");
resolve(doc.querySelector(".phywe-item-accordion"));
};
xhr.onerror = function () {
reject(new Error("item page network error"));
};
xhr.send();
});
}
function parseItemBlocks(scope, withQuantity) {
if (!scope) {
return [];
}
var rows = scope.querySelectorAll(".itemslist .row.itemblocks");
var items = [];
for (var i = 0; i < rows.length; i++) {
var cols = rows[i].children;
if (!cols.length) {
continue;
}
var nameLink = cols[0].querySelector("a");
var numberLink = cols[1] ? cols[1].querySelector("a") : null;
var item = {
name: textOf(nameLink || cols[0]),
mappedTo: textOf(numberLink)
};
if (withQuantity && cols[2]) {
var qty = parseInt(textOf(cols[2]).replace(/[^\d]/g, ""), 10);
item.quantity = isNaN(qty) ? textOf(cols[2]) : String(qty);
}
if (item.name) {
items.push(item);
}
}
return items;
}
function fillTable(tableId, items, withQuantity) {
var table = document.getElementById(tableId);
if (!table || !items.length) {
return;
}
var tbody = table.querySelector("tbody");
for (var i = 0; i < items.length; i++) {
var tr = document.createElement("tr");
var nameTd = document.createElement("td");
nameTd.style.width = "80%";
nameTd.textContent = items[i].name;
tr.appendChild(nameTd);
var numberTd = document.createElement("td");
numberTd.textContent = items[i].mappedTo;
tr.appendChild(numberTd);
if (withQuantity) {
var qtyTd = document.createElement("td");
qtyTd.textContent = items[i].quantity || "";
tr.appendChild(qtyTd);
}
tbody.appendChild(tr);
}
var wrapper = table.parentElement;
while (wrapper && wrapper.className.indexOf("printtablediv") === -1) {
wrapper = wrapper.parentElement;
}
if (wrapper) {
wrapper.style.display = "";
}
}
function stepTitle(stepEl) {
if (!stepEl) {
return "";
}
var titleEl = stepEl.querySelector(".card-header button div") || stepEl.querySelector(".card-header button");
return textOf(titleEl);
}
function setHeadline(tableId, title) {
var headline = document.querySelector("#" + tableId + " .printtableheadline");
if (headline && title) {
headline.textContent = title;
}
}
function parseMedia(scope) {
if (!scope) {
return [];
}
var rows = scope.querySelectorAll(".itemslist .row.itemblocks");
var items = [];
for (var i = 0; i < rows.length; i++) {
var cols = rows[i].children;
if (!cols.length) {
continue;
}
var nameLink = cols[0].querySelector("a");
var fileLink = cols[1] ? cols[1].querySelector("a") : null;
var item = {
name: textOf(nameLink || cols[0]),
mappedTo: textOf(fileLink || cols[1]),
quantity: cols[2] ? textOf(cols[2]) : ""
};
if (item.name) {
items.push(item);
}
}
return items;
}
function fillFromAccordion(accordion) {
if (!accordion) {
return;
}
var versucheStep = accordion.querySelector('[data-step="versuche"]');
var versuche = parseItemBlocks(versucheStep, false);
setHeadline("print-versuche", stepTitle(versucheStep));
fillTable("print-versuche", versuche, false);
var lieferumfangStep = accordion.querySelector('[data-step="lieferumfang"]');
var lieferumfang = parseItemBlocks(lieferumfangStep, true);
fillTable("print-lieferumfang", lieferumfang, true);
var zubehoer = accordion.querySelector('[data-step="zubehoer"]');
var sections = zubehoer ? zubehoer.querySelectorAll(".card-body") : [];
var notwendig = [];
var empfohlen = [];
for (var i = 0; i < sections.length; i++) {
var items = parseItemBlocks(sections[i], false);
if (sections[i].querySelector(".text-red, .icon-warning-black")) {
notwendig = items;
} else if (sections[i].querySelector(".text-green, .icon-Mehrwert_black")) {
empfohlen = items;
}
}
fillTable("print-zubehoer-notwendig", notwendig, false);
fillTable("print-zubehoer-empfohlen", empfohlen, false);
var mediaStep = accordion.querySelector('[data-step="media"]');
var media = parseMedia(mediaStep);
setHeadline("print-media", stepTitle(mediaStep));
fillTable("print-media", media, true);
}
function start() {
var itemUrl = resolveItemUrl();
if (!itemUrl) {
setTimeout(function () {
window.print();
}, 2000);
return;
}
loadAccordion()
.then(function (accordion) {
fillFromAccordion(accordion);
})
.catch(function (err) {
if (window.console && console.warn) {
console.warn("Accordion konnte nicht geladen werden:", resolveItemUrl(), err);
}
})
.then(function () {
setTimeout(function () {
window.print();
}, 500);
});
}
if (document.readyState === "loading") {
document.addEventListener("DOMContentLoaded", start);
} else {
start();
}
})();
Technical data Cannizzaro reaction and reaction of benzaldehyde with ethylene glycolArticle no: P3101600 ![]()
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
Principle In the first part of the experiment, benzaldehyde disproportionates under the effect of alkalis to alcohol-soluble benzyl alcohol and water-soluble benzoic acid that precipitates when the aqueous solution is acidified. In the second part, benzaldehyde reacts with ethylene glycol to form a cyclic acetal. This ethylene acetal is resistant against basic and oxidising reagents. In an acid medium, it once again splits up into its original products. It is because of these characteristics that cyclic acetals are used for blocking the carbonyl function in preparative, organic chemistry. Benefits
Tasks
Learning objectives
Necessary accessories
| ||||||||||||
PHYWE Systeme GmbH & Co. KG
Robert-Bosch-Breite 10 – 37079 Göttingen – Germany
www.phywe.com
Robert-Bosch-Breite 10 – 37079 Göttingen – Germany
www.phywe.com


