【正文】 s Day. More and more young Chinese people begin to celebrate this day in a very similar way as that in western countries. Fewer people than ever will gaze at the heavens on Saturday to pick out the two stars shining bright on either side of the Milky Way, that is, if people even know on which day Qixi falls. There are ready reminders dotted about, in the form of big ads saying Sales on Chinese Valentine39。 Festival. In this day, girls will throw a sewing needle into a bowl full of water on the night of Qixi as a test of embroidery skills. If the needle floats on top of the water instead of sinking, it proves the girl is a skilled embroiders. Single women also pray for finding a good husband in the future. And the newly married women pray to bee pregnant quickly. Tradition transformed The love story of Niulang and Zhinu, and the Qixi Festival have been handed down for generations. Yet these ancient traditions and customs are slowly dying out. Many modern Chinese, particularly youngsters, seem to know more about St Valentine39。s time for the wild fruits to ripe. The picturesque Arxan in Autumn is indeed a fairyland only exists in a dream that satisfies all your fantasies. If it rains heavily on Saturday night, some elderly Chinese will say it is because Zhinu, or the Weaving Maid, is crying on the day she met her husband Niulang, or the Cowherd, on the Milky Way. Most Chinese remember being told this romantic tragedy when they were children on Qixi, or the Seventh Night Festival, which falls on the seventh day of the seventh lunar month, which is usually in early August. This year it falls on Saturday, August 2. Folklore Story As the story goes, once there was a cowherd, Niulang, who lived with his elder brother and sisterinlaw. But she disliked and abused him, and the boy was forced to leave home with only an old cow for pany. The cow, however, was a former god who had violated imperial rules and was sent to earth in bovine form. One day the cow led Niulang to a lake where fairies took a bath on earth. Among them was Zhinu, the most beautiful fairy and a skilled seamstress. The two fell in love at first sight and were soon married. They had a son and daughter and their happy life was held up as an example for hundreds of years in China. Yet in the eyes of the Jade Emperor, the Supreme Deity in Taoism, marriage between a mortal and fairy was strictly forbidden. He ordered the heaven troop to catch Zhinu back. Niulang grew desperate when he discovered Zhinu had been taken back to heaven. Driven by Niulang39。 ll wait in the line for one hour to get a ticket, and another two hours at the site, to only see a tiny bit of the place due to the crowds. Last year, 428 million tourists traveled in China over the weeklong holiday in October. Traveling during this period is a matter that needs thorough preparation. If you are short on time to plan the uping Golden Week it may not be a bad idea to avoid some of the most crowded places for now. There is always a place so fascinating that everyone yearns for. Arxan is a place like this. The beauty of Arxan is everlasting regardless of the changing of four seasons. Bestowed by nature, its spectacular seasonal landscape and mountains are just beyond word. Arxan is a crucial destination for the remended travelling route, China Inner Mongolia Arxan — Hailar — Manzhouli. It is also the joint of the four prairies across the SinoMongolian border, where people gravitate towards the exotic atmosphere mixed with Chinese, Russian, and Mongolia elements. As a historic site for the Yitian Battle, Arxan still embodies the spirit of Genghis Khan. Walking into Arxan, you will be amazed by a kaleidoscope of geous colors all the year round the Spring azaleas blooming red in the snow, the Summer sea wavering blue in the breeze, the Autumn leaves painted in yellow covering volcanic traces, and the Winter woods shining white on the vast alpine snowscape. Hinggan League Arxan city is situated in the far eastern area of Inner Mongolia Autonomous Region. Its full name Haren Arxan means hot holy water in the Mongolian language. Arxan is a tourism city in the northern frontier with a blend of large forest, grand prairies, vast snowfield, heaven lake cluster, thermium, as well as volcanic cluster. It is a rare and unique ecotourism base filled with healthy sunshine, clean air and unspoiled green. Nestled close to the country39。同時(shí)，也要感謝我的企業(yè)指導(dǎo)老師 XXX 師傅，他嚴(yán)謹(jǐn)求實(shí)的工作態(tài)度，做事認(rèn)真的工作作風(fēng)，豐富的實(shí)踐經(jīng)驗(yàn)，扎實(shí)的理論功底，嫻熟的操作技能使我受益匪淺，是我學(xué)習(xí)的榜樣，并且每次都是很細(xì)心地指導(dǎo) 我，即使我犯過那么多錯(cuò)誤，他都是那樣不厭其煩地耐心教導(dǎo)我，在此對(duì)他表示衷心的感謝！ 由于時(shí)間倉促，加之能力有限，我的論文中依然存在很多不足之處，希望各位老師同學(xué)給予批評(píng)與指正。 在大學(xué)的三年里，我學(xué)到了很多，也懂得了很多，感謝母校，感謝老師，感謝同學(xué)們對(duì)我的關(guān)心和愛護(hù)。相信隨著市場(chǎng)的發(fā)展和中國科研力量的不斷加強(qiáng)以 及科研隊(duì)伍的壯大 ， 新的適合消費(fèi)者需求的具有更高質(zhì)量的聚氨酯涂料會(huì)不斷得到開發(fā)和推廣應(yīng)用 。 綠色涂料的開發(fā)和推廣成為 21 世紀(jì)涂料的主要方向。 由于溶劑型聚氨酯涂料對(duì)于人類自身和生態(tài)環(huán)境的嚴(yán)重威脅日益明顯 ， 綠色涂料替代溶劑型涂料成為必 然。現(xiàn)在歐洲水性工業(yè)涂料已占到 40%；在專用涂料領(lǐng)域，目前水性涂料正在以前所未有的速度向汽車修補(bǔ)涂料、防 腐蝕涂料、道路標(biāo)示涂料等所占比重較大的領(lǐng)域發(fā)展。在工業(yè)涂料領(lǐng)域里，歐洲的水性工業(yè)涂料已超過 100 萬噸， 2022 年將達(dá)到 200 萬噸。涂料工業(yè)大致可分為三個(gè)應(yīng)用領(lǐng)域，而水性涂料在最大的兩個(gè)應(yīng)用領(lǐng)域中占有相當(dāng)?shù)谋壤? 真空度最高可達(dá)到 即可，并且在 0 至 范圍內(nèi)可調(diào)壓力，水環(huán)真空泵即可滿足要求 XX 化工職業(yè)技術(shù)學(xué)院 12 4 總結(jié) 水性涂料的發(fā)展趨勢(shì) 隨著科技進(jìn)步和國民經(jīng)濟(jì)的高速發(fā)展，人們的 環(huán)保意識(shí)日趨增強(qiáng)、對(duì)健康的要求越來越高， 環(huán)保法規(guī)也日趨完善，節(jié)資節(jié)能，保護(hù)環(huán)境，已成為全球涂料界面臨的主要問題。 真空泵 在實(shí)際生產(chǎn)過程中，需要考慮的因素有乳液的溫度不得超過 50℃ ，并且丙酮的沸點(diǎn)在常壓下為 ℃ ，所以在常壓下將丙酮加熱分離出來務(wù)必會(huì)嚴(yán)重影 響產(chǎn)品的質(zhì)量。使用回流的方法，為塔頂和塔底有 57℃ 的溫度差提空?qǐng)鏊?，更容易的脫除丙酮? 脫溶劑釜 給脫丙酮提供足夠的空間，攪拌是 反向雙攪拌，大攪拌為框式攪拌，小攪拌為平葉推進(jìn)式攪拌，帶有夾套。在水性聚氨酯乳液的生產(chǎn)過程中，對(duì)所選乳化設(shè)備的主要要求是： 1，攪拌速度快，即能給樹脂以強(qiáng)剪切力，以便使聚氨酯樹脂均勻地分散在水中； 2，轉(zhuǎn)速可調(diào) ,，以便乳化過程中進(jìn)行必要 的反XX 化工職業(yè)技術(shù)學(xué)院 11 應(yīng)。 加熱方式與預(yù)聚釜不同，用熱水加熱，由冷凍水降溫。 中和擴(kuò)鏈釜 聚合完的 預(yù)聚體是在中和擴(kuò)鏈釜完成中和與擴(kuò)鏈反應(yīng)。 熱交換比表面積 / (㎡ /m179。 而且預(yù)聚反應(yīng)是很復(fù)雜的反應(yīng)，往往溫度高會(huì)帶來更多的副反應(yīng)，所以為了加大換熱面積，只會(huì)把預(yù)聚釜做長，但由于裝置限制，也不能做的太長。例如，裝置一臺(tái)容積大一倍的反應(yīng)釜比裝置兩臺(tái)同容積的反應(yīng)釜可降低投資 20%30%，并顯著減少操作費(fèi)用，還可以使產(chǎn)品穩(wěn)定性提高。 我所在的崗位是容積 3 立方米的 反應(yīng)釜 ， 主要由罐體、夾套、傳動(dòng)裝置、軸封裝置、 螺帶和框式復(fù)合式 攪拌、進(jìn)、出料口、容器法蘭以及支座等構(gòu)成 ，由蒸汽加熱，冷凍水降溫 。注意在逐漸提高系統(tǒng)真空度的時(shí)候要注意脫丙酮反應(yīng)釜內(nèi)的乳液狀態(tài)，防止乳液起沫過于嚴(yán)重，從而影響脫丙酮的效率。攪拌