| 5 | 1/1 | 返回列表 |
| 查看: 1477 | 回復(fù): 3 | |||
| 本帖產(chǎn)生 1 個 翻譯EPI ,點擊這里進(jìn)行查看 | |||
| 當(dāng)前只顯示滿足指定條件的回帖,點擊這里查看本話題的所有回帖 | |||
[交流]
關(guān)于物理吸附方面的漢譯英 求高手
|
|||
|
吸附作用一般可以分為兩類,一類是物理吸附(吸附質(zhì)分子和吸附劑之間相互作用主要是范德華力),另一類為化學(xué)吸附(吸附質(zhì)分子和吸附劑之間形成了化學(xué)鍵)。這里我們主要討論利用惰性氣體(一般為N2或Ar)物理吸附方法來表征介孔材料。它也是最常用、最有效的介孔材料表征方法之一。由此,人們可以得到材料的比表面積、孔容、孔徑分布,甚至一些表面性質(zhì)等信息。吸附等溫線一般可以分為六種類型(IUPAC)。I型等溫線在低壓段吸附量存在一個明顯的增加,隨后達(dá)到吸附飽和。一般被認(rèn)為這是單層(多層)吸附和微孔(< 2 nm)被氣體分子填充時得到的吸附等溫線。有時,介孔孔道表面經(jīng)過有機(jī)官能團(tuán)修飾后的氮氣吸附等溫線也會呈現(xiàn)I型曲線,因為此時有機(jī)基團(tuán)會縮小介孔孔徑,到達(dá)微孔范圍。非孔或大孔材料(孔徑 > 50 nm)表面可發(fā)生多層吸附一般會得到II和III型吸附等溫線。III型等溫線是由于吸附質(zhì)分子在固體表面發(fā)生弱的氣-固相互作用形成的,一般不常見。不規(guī)則的介孔材料一般也會產(chǎn)生II和III型吸附等溫線。也有人報道,未除去表面活性劑的介觀材料的吸附等溫線為II型。III型吸附等溫線則常見于水分子在疏水性介孔材料中的吸附。IV和V型吸附等溫線的特點表現(xiàn)為多層吸附后緊接著吸附量急劇增加的毛細(xì)管凝結(jié)。它們是介孔材料典型的吸附等溫線類型。毛細(xì)管凝結(jié)段的吸附量變化越陡峭,表明孔徑分布越均勻。IV和V型吸附等溫線的不同主要表現(xiàn)在多層吸附段,形成原因與II和III型等溫線差別的原因一樣,都是材料的表面性質(zhì)不同造成的。VI型等溫線來源于均勻非孔表面的依次多層吸附。 多謝了! |
» 搶金幣啦!回帖就可以得到:
+1/287
+1/268
+2/50
+1/42
+1/31
+1/22
+1/21
+1/16
+1/12
+1/10
+1/9
+1/9
+1/9
+1/7
+1/4
+1/4
+1/3
+1/3
+1/1
+1/1
| Adsorption is generally classified as physisorption (van der Waals forces dominate between adsorbates and adsorbents) and chemisorption (chemical bonding exists between adsorbates and adsorbents). Here we mainly discuss the utilization of physisorption of inert gasses (generally N2 or Ar) to characterize mesoporous materials. It’s one of the most popular and effective methods for mesoporous material characterization. Such information as specific area, pore volume, pore size distribution and some surface characteristics of the tested material can be obtained using this method. Adsorption isotherms are generally divided into six types (IUPAC). Type I isotherms show an obvious increase of adsorption capacity at low pressure and the subsequent plateau due to saturation of adsorption capacity. Type I isotherms are generally indicative of filling of micropores (< 2 nm) by monolayer gas molecules, but adsorption of N2 onto functional-group-modified mesopores also exhibits this shape sometimes due to the reduction of pore size to the range of micropores by grafting functional groups. Multilayer adsorption can occur on the surfaces of nonporous or macroporous materials, generally showing Type II or III isotherms. Type III isotherms are attributed to weak gas-solid interactions on the solid surface and are not common. Disordered mesoporous materials also generate Type II or III isotherms in general. It has been reported that mesoporous materials with residual surfactants display Type II isotherms. Type III isotherms are commonly obtained when water molecules are adsorbed onto hydrophobic mesoporous materials. Type IV and V isotherms have the characteristics of drastic increase of adsorption capacity caused by capillary condensation after multilayer adsorption and they are typical for mesoporous materials. The more abrupt the change caused by capillary condensation is, the pore size distribution is more uniform. The difference between Type IV and V isotherms mainly lies in the multilayer adsorption stage, and as the difference between Type II and III isotherms, results from different surface properties of solid materials. Type VI isotherms are attributed to successive multilayer adsorption onto homogeneous nonporous surfaces. |
| 最具人氣熱帖推薦 [查看全部] | 作者 | 回/看 | 最后發(fā)表 | |
|---|---|---|---|---|
|
[考研] 0703化學(xué)求調(diào)劑 +7 | 奶油草莓. 2026-03-22 | 8/400 |
|
|---|---|---|---|---|
|
[考研] 081200-314 +3 | LILIQQ 2026-03-27 | 4/200 |
|
|
[有機(jī)交流]
高溫高壓反應(yīng)求助
10+4
|
chibby 2026-03-25 | 4/200 |
|
|
[考研] 0703一志愿9,初試成績:338,四六級已過,有科研經(jīng)歷,求調(diào)劑! +3 | Zuhui0306 2026-03-25 | 3/150 |
|
|
[考研] 316求調(diào)劑 +5 | Pigcasso 2026-03-24 | 5/250 |
|
|
[考研] 315調(diào)劑 +4 | 0860求調(diào)劑 2026-03-26 | 5/250 |
|
|
[考研] 考研調(diào)劑 +9 | 小蠟新筆 2026-03-26 | 9/450 |
|
|
[考研] 324求調(diào)劑 +8 | hanamiko 2026-03-26 | 10/500 |
|
|
[考研] 081200-11408-276學(xué)碩求調(diào)劑 +3 | 崔wj 2026-03-26 | 3/150 |
|
|
[考研] 284求調(diào)劑 +11 | junqihahaha 2026-03-26 | 12/600 |
|
|
[考研] 333求調(diào)劑 +7 | 87639 2026-03-21 | 12/600 |
|
|
[考研] 求調(diào)劑 +5 | 蘆lty 2026-03-25 | 6/300 |
|
|
[考研] 材料考研求調(diào)劑 +3 | Dendel 2026-03-23 | 6/300 |
|
|
[考研] 各位老師您好:本人初試372分 +5 | jj涌77 2026-03-25 | 6/300 |
|
|
[考研] 0854人工智能方向招收調(diào)劑 +4 | 章小魚567 2026-03-24 | 4/200 |
|
|
[考研] 上海電力大學(xué)材料防護(hù)與新材料重點實驗室招收調(diào)劑研究生(材料、化學(xué)、電化學(xué),環(huán)境) +4 | 我愛學(xué)電池 2026-03-23 | 4/200 |
|
|
[考研] 311求調(diào)劑 +3 | 冬十三 2026-03-24 | 3/150 |
|
|
[考研] 一志愿北化315 求調(diào)劑 +3 | akrrain 2026-03-24 | 3/150 |
|
|
[考研] 306求0703調(diào)劑一志愿華中師范 +10 | 紙魚ly 2026-03-21 | 11/550 |
|
|
[基金申請] 請教下大家 2026年國家基金申請是雙盲審嗎? +3 | lishucheng1 2026-03-22 | 5/250 |
|