高氟铝和铝引起低龄鸡骨发育不全

进行了高氟铝和铝对低龄鸡骨损害的实验。５７日龄鸡９６只随机分为８组,毒物加进饲料,实验期３个月。结果表明,各高氟、高氟铝组骨氟均数倍于对照组,低铝组骨氟显著升高;单饲ＮａＦ组骨铝增高近３倍,高氟铝组骨氟比ＮａＦ组和病区玉米组低１／３以上,骨铝低约５０％;单饲铝达对照４～２１倍的骨铝与对照组接近。饲氟与骨氟ｒ＝０．７７,与骨铝ｒ＝０．６５;饲铝与骨铝ｒ＝－０．４６,与骨氟ｒ＝－０．５３;骨氟与骨铝ｒ     

全氟和多氟烷基磺酸的研究XX.二氟甲磺酸二氟甲酯与亲核试剂的反应

二氟甲磺酸二氟甲酯HCF~2SO~3CF~2H(1)和三氟甲碘酸二氟甲酯CF~3SO~3CF~2H(2)相比,在亲核反应中显出较大的差异.由于α-氢的存在,在一定程度上影响了它和亲核试剂的反应,如KF和2作用时得到HCF~3.但与1反应却只进攻其硫原子,得到HCF~2SO~2F(3).而KI与1作用时既可进攻硫又可进攻其烷氧基碳.其它亲核试剂如RCO~2^-,ArS^-等却只进攻1的硫原子.碱性较强的苯酚钠和1作用时除分别进攻硫和碳外,还可攫取其氢原子而产生二氟卡宾.若反应温度较低时,则仅攫取其二氟甲基的氢;若于90℃反应,则还可同时攫取二氟甲氧基的氢,碱性更强的乙醇钠与1反应时则是以攫氢为主.     

全氟和多氟烷基磺酸的研究 ⅩⅩ.二氟甲磺酸二氟甲酯与亲核试剂的反应

二氟甲磺酸二氟甲酯HCF_2SO_3CF_2H(1)和三氟甲磺酸二氟甲酯CF_3SO_3CF_2H(2)相比,在亲核反应中显出较大的差异.由于α-氢的存在,在一定程度上影响了它和亲核试剂的反应,如KF和2作用时得到HCF_3.但与1反应却只进攻其硫原子,得到HCF_2SO_2F(3).而KI与1作用时既可进攻硫又可进攻其烷氧基碳.其它亲核试剂如RCO_2~-、ArS~-等却只进攻1的硫原子.碱性较强的苯酚钠和1作用时除分别进攻硫和碳外,还可攫取其氢原子而产生二氟卡宾.若反应温度较低时,则仅攫取其二氟甲基的氢;若于90℃反应,则还可同时攫取二氟甲氧基的氢.碱性更强的乙醇钠与1反应时则是以攫氢为主.     

α′-三氟甲基含氟β-二酮的合成

为了合成手性含氟β-二酮顺磁性镧系螯合物作为~1H NMR手性位移试剂,我们曾试图用2-三氟甲基-3-氧杂八氟己酸乙酯与3,3-二甲基-2-丁酮(1)在乙醇钠存在下进行Claisen酯缩合反应合成β-二酮,结果只发生氟仿型反应,生成碳酸二乙酯.若用三氟乙酸乙酯与1,I,1-三氢_3,6-二(三氟甲基)-4,7-二氧杂-2-十一氟癸酮在乙醇钠存在下反应,也得到氟仿型反应产物2-氢-5-三氟甲基-3,6-二氧杂-十四氟壬烷(2).本文采用碱性较弱的     

F+HC≡CH→HC≡C+HF反应的理论研究

在大气化学和燃烧历程的研究中，只含两个碳原子的碳氢化合物自由基的研究占有很重要的地位．乙炔与氟原子的反应是实验室制取HCZC·自由基的重要方法．因此乙炔与氟原子的反应在动力学研究中一直很受重视．乙炔与氟原子的反应存在有以下三种反应方式问：门抽取反应：F＋C。H。     

硅酸及其盐的研究 Ⅴ.氟离子和硅酸的聚合作用

在較广的pH范围內,测定氟离子对硅酸(酸化的水玻璃和单硅酸鈉)胶凝作用的影响。在中性和微碱性溶液中,氟离子促进硅酸胶凝,而且这作用随所加氟离子数量而加大。在酸性溶液中,氟离子也有促凝作用,并随氟离子增多而增加。但只增加到一定限度,过此限度,促凝作用卽行減退。所生凝胶的离浆溶液合氟量亦已测定。在碱性溶液,氟离子全部在离浆液中,表示氟离子不参加凝胶的組成而仅起催化作用。在酸陸溶液,氟离子全部或大部分在凝胶內,这表示它不仅参与反应而且是产物的組成部分。根据以前所提硅酸聚合的机制,对所观測到的結果作初步的解释。     

静态顶空-气相色谱-质谱法分析废水中苯系物的内标物优选

采用静态顶空-气相色谱-质谱法同时测定废水中8种苯系物含量时,根据目标物与内标物响应值变化趋势的相似性,对内标物的选择进行优化。结果表明:氟苯和甲苯-D8分别适合作为苯和甲苯的内标物,而4-溴氟苯更适合作为乙苯、二甲苯、苯乙烯和异丙苯的内标物。与只采用氟苯作为内标物相比较,内标物优化后有利于提高分析方法的准确度和精密度。     

铂重整条件下烴类转化的机理和动力学Ⅳ. 关于铂重整催化剂的双重性问题

用环己烷、环己烯、甲基环戊烷和甲基环戊烯等四种單体烴,分别在鉑-氧化鋁、氟氫酸-氧化鋁以及鉑-氟氫酸-氧化鋁三种催化剂上进行反应。發現鉑-氟氫酸-氧化鋁不論在脱氫或异构化以及异构脱氫等反应上都比前两种催化剂的性能优越。同时也發現鉑-氧化鋁与氟氫酸-氢化鋁并非只具有脫氫或异构化性能的單功能催化剂,而是活性較差的双功能催化剂,在鉑-氧化鋁中加入氟氫酸或在氟氫酸-氧化鋁中加入鉑以后,就都成为活性很好的双功能催化剂。根据这些結果,我們提出了鉑与氟氫酸在催化剂表面形成活性集团(或复合活性中心)的假說,并根据这种假說与試驗結果,提出了甲基环戊烷芳烃化的轉化历程,其中甲基环戊烯的异构化是最慢的步驟。     

铝和铝氟病鸡模型全血骨元素和血清生化骨矿含量骨形态学的相关研究

复制了铝危害和铝氟病鸡模型。将100日龄84只雄性种鸡随机分为7个组,毒物加进配合饲料自由摄食,实验3个月。结果表明,高铝、高氟、高氟铝组在实验3周内全血多种元素和7周内的血清生化物质含量及其相关性便发生显著变化,实验13周性成熟后出现逆转并接近正常。均引骨骼元素含量、骨细胞、骨胶元、骨组织形态、骨矿代谢、骨塑形和骨骼力学机能的病理变化。性成熟后饲料加氟与未加氟各3个组的全血铁、磷、血清钙、GRT才出现分异,并与骨矿代谢动态参数的分异相吻合。表晨本实验性成熟前诸多病变主要是铝危害引起。铝可较长期使全血锌和和骨锌含量下降。全血元素含量和相关性的变化是受机体内环境影响较大的动态变化过程。骨代谢联系着广泛的生物无机化学基础。性成熟后高氟、高氟铝、高铝的危害尚有各自的特点。     

氟化钠对大鼠血清微量元素的影响

为探讨氟化钠（NaF）对大鼠血清四种微量元素含量的影响,将80只2月龄SPF级SD大鼠,雌雄各半,随机分成8组：对照组[幼年（CS）、成年（AS）]和用药组[幼年高氟（CHS）、成年高氟（AHS）平订幼年低氟（CLS）、成年低氟（ALS）组,长期高氟（HS）和低氟（LS）组];对照组灌胃生理盐水,刖药组分别按相应时阃给予不同剂量的NaF灌胃。结果表明,与CS组相比,CYIS组和CLS组的P分别增加100％（P〈0．05）和193．8％（P〈0．05）;与As组相比,HS组的Ca、Zn分别下降了20．5％（P〈0．05）和40％（P〈0．05）,而P则增加了74％（P〈0．05）,LS组的Zn也下降了33．3％（P〈0．05）。提示：长期使用氟化钠可导致幼年大鼠血中化学元素代谢紊乱。     

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.     

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.     

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.     

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.     

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.     

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.     

Microwave-assisted copper-catalyzed stereoselective ring expansion of three-membered heterocycles with α-diazo-β-dicarbonyl compounds

Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular S_N2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.