2023年全國碩士研究生考試考研英語一試題真題(含答案詳解+作文范文)_第1頁
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1、<p><b>  附錄</b></p><p><b>  外文文獻(xiàn)原文</b></p><p>  About gravity qing separator is discussed some problems</p><p>  According to the content and gravity qi

2、ng separator for dry bulk density, liquidity, choose the clear separation. This equipment often used in improving seed, grain,minerals and recycling material quality products. This paper stated the gravity clear how to w

3、ork there, working with the use of material is gravity clear separator adapt, how to select the gravity qing separator, gravity qing separator mesa of the mixed zone seed treatment and gravity, there have a good clear in

4、vestment prospects.</p><p>  If the material contains light impurity, mildew metamorphic seeds, weed seeds and heavy impurity,So can use gravity qing separator, through the material of it from the material i

5、n bulk density points To improve the material from out of the quality. For instance in processing seeds and grain process, do not The full, worms cracking seeds (grain), not mature, mildew seeds (valley Content), weed se

6、eds,Small stones from good seeds (grain) of separation of to improve Seed germination rate and clarity</p><p>  However, not every kind of material can be gravity high efficiency in the qing qing separator c

7、hoose points From, sometimes use many sets of gravity when the qing qing separator material chosen separation effect is not obvious The. Here there how to work the gravity. How to determine whether the material and gravi

8、ty Qing separator adapt.</p><p>  1 there is clear how gravity</p><p>  1. 1 gravity structure of qing separator</p><p>  1. 1. 1Typical of the gravity qing separator by frameWith a

9、 sieve net, material of conducting bar torque Form vibration mesa (or triangle mesa), one or more Taiwan fan, wind room, feed hopper,Discharging system, CVT institutions.</p><p>  1. 1. 2 general mesa change

10、 from 46 cm x 92 cm to 183 cmx457. 5 cm, mesa in two directions Angle can be adjusted.</p><p>  1. 1. 3 feeding device installed in the washing machine of gravity (at least for 15 minutes or more consecutive

11、 materials; next, mesa high above the edge. Feeding device may have condiment door,Through the material door can increase or decrease the mesa of material flow. Mesa have three materials Row export, heavy material and li

12、ght material row in feeding and export mouth relative low mesa Edge, of course, intermediate product material row in heavy material and export light material among expor</p><p>  1. 1. 4 vibration device ins

13、talled in the bottom of the table, a kind of eccentric movement for vibration.A fan or a group of fans also be placed in the table below. Automatic control panel and laid it inMesa make handlers beside convenient to cons

14、ole the dip Angle, vibration frequency and windVolume.</p><p>  1. 2 working principle</p><p>  1.2.1 material layer</p><p>  At work, the material from bunker eduction, flows throu

15、gh feeding device to gravity clear choice Machine woven nets mesa, mesa is mainly along the vertical vibration, mesa vibration frequency For 200 time/minutes to 600 times/minutes. The vibration of the mesa and air flow t

16、o make materials spread And a fluid state. Air through the wind chamber spread to mesa on screen mesh, through the control gas Flow make mesa material produce the layer (and not light material be given heavier blow in ma

17、teria</p><p>  1. 2.2 things shake separation</p><p>  Vibration in two direction mesa have tilt, to promote material separation and discharging in Mesa material stratification, because the mesa

18、 vibration influence, mesa heavier particles due to the ground Wipe the force ACTS to mesa high edge mobile, heavy material on the mesa "the crawling" to mesa high Edge, and float in heavy material above the li

19、ghter particles, by gravity to lower edge mobile, So the material into a vertical stratification level separation. Heavy material over the edge of the </p><p>  1. 2. 3 material choose clear separation is th

20、e premise of material layer, material layered regional general From feed mouth began to no more than a third of the mesa, only the material fully stratification, just Can make different density of material completely sep

21、arate.</p><p>  1. 2. 4 material into the gravity there must be approved by a clear before the washing to remove material in the screen Most of the chaff, leaf stalks and big miscellaneous, then into the gra

22、vity of the separator basic materials On similar appearance, just on the density change.</p><p>  2 how to choose a gravity clear there</p><p>  In determining the material of the gravity clear

23、the adaptability of the separator, the next step is to content Material in clear on the gravity there, to determine the most suitable for the gravity of the material washing qing.</p><p>  2. 1 provide sampl

24、e</p><p>  The premise of the test is to provide adequate test first material sample. For big The gravity model clear separator, need to provide several tons of material make it can pack to gravity clear sto

25、re there After the storehouse for feeding and processing, gravity for lab sorting machine, you are required to offer 57g Or so the material sample.</p><p>  2.2 analysis gravity clear separation of the good

26、material washing and abandon material sample </p><p>  (1) good material quality whether meet your requirements, material quality improvement of process How degrees. (2) rejected material is how many, reject

27、ed material in the content of good material How much? The machining process of good material in the future if can recycle. (3) as gravity qing separator try Check the results, and the material quality be dropped, the qua

28、lity descend the reason is to adjust (such as mesa vibration Still need to reduce) or storage, material feeding device, Discharg</p><p>  2.3 the material mouth was different materials bulk density</p>

29、<p>  Through the determination of the material KouChong different material and light material differences reflect gravity qing The qing choose washing effect. For seed batch of speaking, in the determination of b

30、ulk density, meanwhile, the different Material of the seed germination rate and mouth clarity in a seed checkout room.</p><p>  3 Gravity qing separator mixed zone materials handling</p><p>  3.

31、1 the T-shirt material by gravity after washing the intermediate product material (about 20% or so) The problem is more trouble between. According to domestic common practice is intermediate product materials for again T

32、he gravity of the separator feeding mouth. Gravity enter the homework after washing the state, each unit Several are stable, by gravity of intermediate product material clear separator, the second time There is a clear g

33、ravity in the form of intermediate product material discha</p><p>  3.2 foreign to this problem puts forward more objective practice, they say the feeling Often appear in the form. General intermediate produ

34、ct material by heavy small materials and light big materials group Become, will intermediate product materials into the wind to screen the separator (and not gravity feed entrance qing Separator entrance) hello again a s

35、creening and, to some extent, improve the physics properties of materials (xi 1, form Size), be helpful for gravity qing separator" Light "go</p><p><b>  外文文獻(xiàn)譯文</b></p><p>

36、  關(guān)于重力清選機幾個問題的探討</p><p>  重力清選機根據(jù)物并的容重對干燥的、有流動性的順拉進行清選分離。這種設(shè)備經(jīng)常應(yīng)用在改進種子、谷物、礦物和回收物質(zhì)的產(chǎn)品品質(zhì)。本文主要陳述了重力清選機如何工作, 所加工的物料是否與所使用的重力清選機相適應(yīng), 如何選擇重力清選機, 重力清選機臺面混合區(qū)種子處理及所納重力清選機是否有好的投資前景。</p><p>  如果物料中含有輕雜質(zhì)、霉?fàn)€

37、變質(zhì)種子、雜草種子和重雜,那么可以使用重力清選機, 通過物料的容重將它們從物料中分離出來以改進物料的品質(zhì)。比如在加工種子和谷物過程中, 不飽滿的、被蟲子磕過的種子(谷物) 、不成熟的、霉?fàn)€種子(谷</p><p>  物) 、雜草種子、小石子從好的種子(谷物) 中分離出來, 以提高種子凈度和發(fā)芽率.然而并不是每一種物料都能被重力清選機高效地清選分離, 有時使用多臺重力清選機時物料的清選分離效果仍不顯著。下面介紹重

38、力清選機如何工作。如何確定是否物料與重力清選機相適應(yīng), 怎樣選擇一臺重力清選機, 重力清選機臺面混合區(qū)種子處理及是否有好的投資前景.</p><p>  1 重力清選機是怎樣工作的 </p><p>  1.1 重力清選機的結(jié)構(gòu)</p><p>  1.1.1 典型的重力清選機由機架、帶有篩網(wǎng)、有物料導(dǎo)條的矩形振動臺面(或三角形臺面) 、一臺或多臺風(fēng)機、風(fēng)室、喂

39、料斗、排料系統(tǒng)、無級變速機構(gòu)組成。</p><p>  1.1.2 一般臺面變化從46cmx92cm~183cmx457cm ,臺面兩個方向的角度可以調(diào)整。</p><p>  1.1.3 喂入裝置安裝在重力清選機料倉(至少連續(xù)供物料15分鐘以上〕下面, 臺面高邊上面。喂入裝置上有可調(diào)料門, 通過料門可以增加或減少臺面上的物料的流量。臺面上有三個物料排出口, 重物料和輕物料排出口設(shè)在與喂料

40、口相對的臺面低</p><p>  邊, 當(dāng)然, 中級品物料排出口設(shè)在重物料和輕物料出口中間。</p><p>  1.1.4 振動裝置安裝在臺面的下方, 振動為一種偏心運動。一臺風(fēng)機或一組風(fēng)機也被安置在臺面下方。自動控制面板安放在臺面旁邊使操作者能夠方便地控制臺面的傾角、振動頻率和風(fēng)量。</p><p><b>  1.2 工作原理</b>&

41、lt;/p><p>  1.2.1 物料分層</p><p>  在工作時, 物料從料倉排出, 流經(jīng)喂入裝置到達(dá)重力清選機編織網(wǎng)臺面上, 臺面振動主要是沿縱向進行, 臺面振動頻率為20 0 次/ 分鐘到60 次/ 分鐘。臺面的振動和氣流使物料擴散而呈流體狀態(tài)。氣流通過風(fēng)室擴散到臺面篩網(wǎng)上, 通過控制氣流使臺面物料產(chǎn)生分層(而不是輕的物料從重物料中吹出來) ,重物料仍保持在臺面上, 輕物料在氣流

42、作用下離開臺面浮在重物料上面。這時物料處于分層區(qū)。臺面上的物料分布在物料導(dǎo)條之間, 有助于臺面物料均勻過渡。</p><p>  1.2.2 物抖分離</p><p>  振動臺面在兩個方向都有傾斜, 以促進物料分離和排料在臺面物料分層后, 由于臺面振動影響, 臺面上較重顆粒由于磨擦力作用向臺面高邊移動, 重物料貼著臺面“ 爬行”到臺面的高邊, 而浮在重物料上面較輕的顆粒, 在重力作用下向

43、低邊移動,于是物料垂直分層變?yōu)樗椒蛛x。重物料越過臺面高邊的活板門, 流出臺面進入重物料排出口; 同時, 輕物料流向臺面的低邊, 進入輕物料排出口。于是重力清選機完成了物料的分離過程。中等比重范圍內(nèi)的顆粒被稱為中級品, 中級品從重、輕物料排出口中間的區(qū)域進入其排料口。</p><p>  1.2.3 物料清選分離的前提是物料分層, 物料分層區(qū)域一般從喂料口開始不超過臺面的3 分之1 , 只有物料充分分層, 才能使

44、不同容重的物料徹底分離。</p><p>  1.2.4 物料進入重力清選機之前須經(jīng)風(fēng)篩清選機除去物料中大部分的谷殼、葉梗和大雜, 那么進入重力清選機的物料基本上外形相似, 只是容重上有變化。</p><p>  2 如何選擇一臺重力清選機</p><p>  在確定了物料對重力清選機的適應(yīng)性后, 下一步則需要物料在重力清選機上試驗, 以確定最適合物料的重力清選機。

45、</p><p><b>  2.1 提供樣品</b></p><p>  做好試驗的前提首先是提供充足的試驗物料樣品。對于大型重力清選機, 需要提供幾噸物料使它能夠裝至重力清選機儲倉后連續(xù)喂入和加工, 對于試驗室重力精選機, 則需提供579左右的物料樣品。</p><p>  2.2 分析重力清選機分離出的好物料和所棄物料樣品</p&g

46、t;<p>  (1) 好物料的品質(zhì)是否符合你的要求, 物料品質(zhì)提高的程度如何。(2 ) 棄掉的物料有多少、棄掉的物料中好物料的含量有多少? 今后的加工中好物料是否能回收。(3) 作為重力清選機試驗結(jié)果, 物料品質(zhì)是否下降, 品質(zhì)下降是調(diào)整的原因(如臺面振動需要減少)還是儲倉、料喂器、排料口、提升機的原因。(4 )清選分離效果是否一次能達(dá)到。如果不能達(dá)到, 能否換一臺大型重力清選機, 在生產(chǎn)率的下限加工物料使物料有一個長的

47、分離過程以改進分離效果.</p><p>  2.3 測定不同出料口物料容重</p><p>  通過測定不同出料口重物料與輕物料的差異反映重力清選機的清選效果。對于種子批來講, 在測定容重的同時, 不同出料口種子的凈度和發(fā)芽率可以在種子檢驗室做出來。</p><p>  3 重力清選機混合區(qū)物料處理</p><p>  3.1 恤料經(jīng)過重力

48、清選機后的中級品物料(約占20 %左右)是較為麻煩的間題. 按國內(nèi)的一般做法是中級品物料又重新投入重力清選機的喂料口。重力清選機進入作業(yè)狀態(tài)后, 各個參數(shù)都是穩(wěn)定不變的, 經(jīng)過重力清選機的中級品物料, 第二次經(jīng)過重力清選機時依然以中級品物料的形式排出。重力清選機作業(yè)幾個小時后, 中級品物料越積越多, 再加上正常的物料喂入,重力清選機不堪重負(fù), 清選效果下降, 降低了成套設(shè)備使用效果(對于小麥種子重力選是最后一道工序, 對于玉米種子目前分

49、級工序雖然有, 但使用不多, 因而重力選也是最后一道工序。)有時重力清選機前邊的風(fēng)篩清選機只好停機等待重力清選機“消腫” 后再啟動, 整個流水線不是真正意義上的流水線。</p><p>  3.2 這種情形經(jīng)常出現(xiàn)。一般中級品物料由重的小物料和輕的大物料組成, 將中級品物料重新投入風(fēng)篩清選機喂入口(而不是重力清選機喂入口)再篩選一次, 一定程度上改善物料物理性狀(外形尺寸) , 有利于重力清選機“輕裝”上陣, 使

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