Whenpyridine was used as reductive decomposing agent, the expecting cholest-4-en-3,6-dione-22-al was obtained. However, when Zn/HOAc was used to decomposethe ozonide, C-4,5 double bond was further reduced to give cholest-3,6-dione-22-al as main product. 2 For the side-chain construction of compound (1), the solid-liquid phase-transfer Wittig reaction was used. When (3-methyl-2-oxobutyl)-triphenylarsonium bromide was used as reagent, the reaction can be carried out inmild reaction condition and the yield is higher than that when phosphorane wasused.

但使用Zn／HOAc作為分解劑時(shí)亚洲一区国产精品，卻得到其氫化產(chǎn)物膽甾-3， 6-二酮-22-醛；2在甾體支鏈引入過程中，采用固-液相轉(zhuǎn)移Wittig反應(yīng)的方法在线A片毛视频，用(3-甲基)-2-氧丁基三苯基溴化胂作為試劑，反應(yīng)在非常溫和的條件下便可完成一区毛片，而且產(chǎn)率比傳統(tǒng)采用膦烷的方法更高；3在對某些甾酮化合物的選擇性還原反應(yīng)研究時(shí)www.99riavcom，發(fā)現(xiàn)在〓還原體系中中文国产原创在线观看网站，當(dāng)加入某些金屬離子后，反應(yīng)有更好的區(qū)域選擇性和立體選擇性在线国产福利影院。

The best compost of catalytic-oxidation is scalpped by perpendicular experiment,the best fugitive conditions arestudied in the best of the reaction between sulphuric acid- potassium bromide and sodium iodate .

研究了在3.0mol/L的硫酸介質(zhì)中国产1000黄色网站，溴化鉀催化碘酸鈉氧化偶氮胂M褪色反應(yīng)的適宜條件與影響因素，建立了催化動力學(xué)褪色光度法測定痕量碘的新方法性交小说在线观看。

Until now the drug melarsoprol was used to treat patients in the advanced stage of sleeping sickness.

直到現(xiàn)在欧美一区性爱视频，美拉胂醇依然被應(yīng)用在昏睡病晚期病人的治療中。

In the presence of tartaric acid (pH=1.5), stripping and determination of uranium are completed.

在pH =1 5的酒石酸存在下国产噜噜观看，水相樣品可以直接顯色測定天天色,天天干,天天日，有機(jī)相樣品用偶氮胂Ⅲ溶液反萃其中的U并同時(shí)顯色測定。

The optimum reaction conditions and the influencing factors were studied. In the presence of gum arobic, arsenazo Ⅲ-barium in acid solution could combine with BSA to form a ternary complex leading to a redshift of absorption spectrum and significant increase of absorption peak intensity.

研究發(fā)現(xiàn)国产三级片一区,二区在线，在表面活性劑阿拉伯樹膠存在下的酸性溶液中超碰免费在线站长工具，偶氮胂Ⅲ-Ba配合物與BSA發(fā)生反應(yīng)形成三元復(fù)合物，引起吸收光譜發(fā)生紅移只久久久久久久久久久，吸收峰明顯增高国产特黄特色视频网站。

0 Mg·L-1 of roxarsone and arsanilic acid by stactic system and semi-stactic system.

L-1洛克沙胂、阿散酸的動力學(xué)過程日韩系列精品自拍视频在线观看。

Arsanilic acid ; Growing - pig ; Nutrient ; Digestive tract

對氨基苯胂酸午夜在线色呦呦；豬；營養(yǎng)物質(zhì)欧美熟女性爱图；消化道

Mixing ratios between paraand ortho-tolyl arsonic acids ranging from 50:50 to 30:70 were effective with a peak value at 45:55 in which a maximum collecting capacity was obtained.

為降低藥劑成本亚洲网站黄色，利用化工廠廢棄的冷母液制造混合甲苯胂酸，在工業(yè)生產(chǎn)中證明是十分成功的亚洲一区二区三区性爱视频。

The mixed collectors studied were as following: benzyl arsonic acid-sodium butyl xanthate for walframite flotation, salicylohydroxamic acid-F〓, salicylohydroxamic acid-cupferron, salicylohydroxamic acid-TBP , F〓-TBP, cupferron-benzohydroxamic acid etc. for cassiterite flotation and mixed aliphatic acid or aliphatic amine for beryl or spodumene flotation.

研究過程中视频偷拍，本文選用了如下具體實(shí)例：芐基胂酸與丁基黃藥浮選黑鎢礦，水楊羥肟酸與F〓aV女同一级毛片、水楊羥肟酸與銅鐵靈在线观看中文字幕码2018、水楊羥肟酸與磷酸三丁酯、F〓與磷酸三丁酯中文字幕日韩一区、銅鐵靈與苯異羥肟酸兩兩結(jié)合浮選錫石国产污污污在线观看免无毒，混合脂肪胺與混合脂肪酸浮選鋰輝石與綠柱石。

These possible mechanisms for the synthetic reaction and thesubstitution reaction of α-hyperiodine group arsonium ylides were proposed.

將它與親核試劑作用；產(chǎn)生α-硒代或α-硫代胂葉立德免费观看黄页网站，提出了先配位后配體偶聯(lián)的可能反應(yīng)機(jī)理www.欧美亚洲精品。