MethylomonasZ201细胞在戊二醛活化DEAE—纤维素上的共价固定化

以戊二醛活化的ＤＥＡＥ－纤维素为载体，采用共价键法固定化ＭｅｔｈｙｌｏｍｏｎａｓＺ２０１细胞，固定化细胞催化丙烯环氧化的最优细胞／载体比为３２ｍｇ干重细胞，最适ＰＨ值达温度分别为７．８和３５℃，用纯氧代替空气作为氧源，分别使游离和固定化细胞的ＭＭＯ活性提高了８％和３５％，外泊性电子给体甲酸钠对固定化细胞ＭＭＯ活性的激发作用小于游离细胞，失活动力学分析结果表明，固定化细胞的稳定性高于游离细胞。     

固定化Methylomonas Z201细胞：甲烷单加氧酶的活性和稳定性

分别以海藻酸钙和砂子为载体，采用包埋和吸附技术固定化ＭｅｔｈｙｌｏｍｏｎａｓＺ２０１细胞．以丙烯环氧化为指标反应，系统研究固定化对ＭｅｔｈｙｌｏｍｏｎａｓＺ２０１细胞ＭＭＯ活性和稳定性的影响．结果表明，对包埋细胞，合适的负载量和粒径为保留较高ＭＭＯ活性所必需．砂子对细胞的吸附能力中等．外源性电子给体甲酸钠对游离和固定化细胞的ＭＭＯ活性影响不同．固定化细胞的最适ｐＨ值和温度与游离细胞相同，但活化能降低．固定化细胞保留游离细胞ＭＭＯ活性的６０—７０％，操作稳定性、热稳定性、贮存稳定性均有所提高．     

METHANE DEHYDROGENATION AND AROMATIZATION IN THE ABSENCE OF O_2 OVER Mo/HZRP-1 A Study on the Interaction between Mo Species and HZRP-1 by Using ~(27)Al and ~(31)P MAS NMR

ＭＥＴＨＡＮＥＤＥＨＹＤＲＯＧＥＮＡＴＩＯＮＡＮＤＡＲＯＭＡＴＩＺＡＴＩＯＮＩＮＴＨＥＡＢＳＥＮＣＥＯＦＯ２ＯＶＥＲＭｏ／ＨＺＲＰ１ＡＳｔｕｄｙｏｎｔｈｅＩｎｔｅｒａｃｔｉｏｎｂｅｔｗｅｎＭｏＳｐｅｃｉｅｓａｎｄＨＺＲＰ１ｂｙＵｓｉｎｇ２７Ａｌａ...     

EFFECTS OF STEAM ON THE STRUCTURE OF Pt-Sn/MgAl_2O_4 CATALYSTS STUDIED BY X-RAY DIFFRACTION

ＥＦＦＥＣＴＳＯＦＳＴＥＡＭＯＮＴＨＥＳＴＲＵＣＴＵＲＥＯＦＰｔＳｎ／ＭｇＡｌ２Ｏ４ＣＡＴＡＬＹＳＴＳＳＴＵＤＩＥＤＢＹＸＲＡＹＤＩＦＦＲＡＣＴＩＯＮＤｏｎｇＷｅｎｓｈｅｎｇ，，ＷａｎｇＸｉｎｋｕｉ，ＰｅｎｇＳｈａｏｙｉ（ＳｈａｎｘｉＩｎｓｔｉｔ...     

谷氨酸脱羧酶在新型羧甲基化交联烯丙基葡聚糖凝胶树脂上的 …

本文首次用合成的羧甲基化的以Ｎ，Ｎ’－甲叉双丙烯酰胺交联的烯丙基葡聚糖（简称ＣＭ－ＣＡＤＢ）凝胶生化树脂为新型载体，研究了谷氨酸脱羧酸在ＣＭ－ＣＡＤＢ树脂上的固定化与环境的信赖关系。确定了酶固定化最佳条件：缓冲体系为ｐＨ４．４，０．１０ｍｏｌ／Ｌ磷酸氢二钠－０．０５ｍｏｌ／Ｌ柠檬酸，载体为交联度３５％，交换容量３．０ｍｅｑ／ｇ的ＣＭ－ＣＡＤＢ凝胶树脂，吸附平衡时间４ｈ以上，酶用量为３０．０ｍｇ／ｇ     

Cu_4-Co-Fe OXIDE CATALYST FOR CYCLOPROPANATION OF 1,1-DICHLORO-4-METHYL-1,3-PENTADIENE WITH METHYL DIAZOACETATE

Ｃｕ４ＣｏＦｅＯＸＩＤＥＣＡＴＡＬＹＳＴＦＯＲＣＹＣＬＯＰＲＯＰＡＮＡＴＩＯＮＯＦ１，１ＤＩＣＨＬＯＲＯ４ＭＥＴＨＹＬ１，３ＰＥＮＴＡＤＩＥＮＥＷＩＴＨＭＥＴＨＹＬＤＩＡＺＯＡＣＥＴＡＴＥＨｕＸｉｎｑｕａｎ１，ＺｈｅｎｇＺｈｕｏ１，Ｘ...     

双稀土氟氧化物Sm-La-O-F催化剂的AFM研究

双稀土氟氧化物ＳｍＬａＯＦ具有良好的乙烷氧化脱氢（ＯＤＥ）催化性能，特别是对于Ｓｍ２Ｏ３ＬａＦ３（１∶１摩尔比），在９７３Ｋ，乙烯选择性为８９７％，乙烷转化率为２２１％，是目前报道的具有高乙烯选择性的ＯＤＥ反应催化剂．比表面积和ＸＲＤ测试表明，Ｓｍ２Ｏ３ＬａＦ３催化剂体相是由单一相结构的双稀土氟氧化物Ｓｍ２／３Ｌａ１／３ＯＦ组成，比表面积较小．原子力显微镜（ＡＦＭ）研究表明，该催化剂的表面颗粒排布规整致密，粒径均匀；而其它乙烯选择性较低的催化剂颗粒排布较为松散，颗粒大小不一．     

STUDY ON REDUCTION MECHANiSM OF1，5－DIAMINO －4．8－DIHYDROXYANTHRAQUINONE ELECTROLYSIS

ＳＴＵＤＹＯＮＲＥＤＵＣＴＩＯＮＭＥＣＨＡＮｉＳＭＯＦ１，５－ＤＩＡＭＩＮＯ－４．８－ＤＩＨＹＤＲＯＸＹＡＮＴＨＲＡＱＵＩＮＯＮＥＥＬＥＣＴＲＯＬＹＳＩＳＣｈｕｎＡｎＭＡ（ＣｈｅｍｉｃａｌＥｎｇｉｎｅｅｒｉｎｇＤｅｐａｒｔｍｅｎｔ，ＺｈｅｊｉａｎｇＵ...     

n-BUTANE ISOMERIZATION ON Al-PROMOTED SULFATED ZIRCONIA CATALYSTS

ｎＢＵＴＡＮＥＩＳＯＭＥＲＩＺＡＴＩＯＮＯＮＡｌＰＲＯＭＯＴＥＤＳＵＬＦＡＴＥＤＺＩＲＣＯＮＩＡＣＡＴＡＬＹＳＴＳＸｉａＹｏｎｇｄｅ，ＨｕａＷｅｉｍｉｎｇ，ＭｉａｏＣｈａｎｇｘｉ，ＧａｏＺｉ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，Ｆｕ...     

CeO2在Pd/γ-Al2O3催化剂中的助剂作用

用色谱微反流动法技术考察了富氧和贫氧条件下,添加ＣｅＯ２对Ｐｄ／γＡｌ２Ｏ３催化剂上ＣＯ氧化反应的影响,并运用ＴＰＲ、ＴＰＤＭＳ及ＳＥＭ等技术研究了ＣｅＯ２Ｐｄ／γＡｌ２Ｏ３催化剂．结果表明：ＣｅＯ２、Ｐｄ的共助作用使ＣｅＯ２Ｐｄ／γＡｌ２Ｏ３催化剂ＴＰＲ还原峰温向低温方向移动;ＣｅＯ２的存在使Ｐｄ／γＡｌ２Ｏ３催化剂表面的吸附氧容易脱出,从而改善了催化剂的氧化活性;ＣｅＯ２、Ｐｄ间的强相互作用使催化剂上Ｐｄ元素的分散程度增加．     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.