三辛胺萃取酸过程的稀释剂效应

研究了三辛胺萃取酸过程的机理,得到三辛胺与强酸生成离子缔合型萃合物,与弱酸生成分子型萃合物。对强酸需要克服水化作用,其萃取能力小于弱酸,其分配比与酸根离子的离子势有关。萃取弱酸时,分配比与酸分子的大小和性质有关。萃取弱酸的稀释剂效应显著,可使分配比提高30～70倍。三辛胺对羧酸的萃取能力取决于萃合物与稀释剂的相互作用能力及其在稀释剂中的疏溶作用,相互作用能力越强,疏溶作用越弱,越有利于萃取。     

Exploration of Novel Co-processed Multifunctional Diluent for the Development of Tablet Dosage Form

The aim of this investigation was to develop a novel multifunctional co-processed diluent consisting of microcrystalline cellulose (Avicel PH 102), crospovidone (Polyplasdone XL) and polyethylene glycol 4000. Colloidal silicon dioxide and talc were also incorporated as minor components in the diluent to improve tableting properties. Melt granulation was adopted for preparation of co-processed diluent. Percentage of Avicel PH 102, Polyplasdone XL and polyethylene glycol 4000 were selected as independent variables and disintegration time was chosen as a dependent variable in simplex lattice design. The co-processed diluent was characterised for angle of repose, bulk density, tapped density, Carr''s index, percentage of fines and dilution potential study. Acetaminophen and metformin were used as poorly compressible model drugs for preparation of tablets. The blend of granules of drug and extra-granular co-processed diluent exhibited better flow as compared to the blend of drug granules and physical mixture of diluents blend. The diluent exhibited satisfactory tableting properties. The tablets exhibited fairly rapid drug release. In conclusion, melt granulation is proposed as a method of preparing co-processed diluent. The concept can be used to bypass patents on excipient manufacturing.     

Crystallization and Morphological Features of Syndiotactic/Atactic Polystyrene Blends at High Temperatures

Crystalline/amorphous binary mixtures of polystyrene with different tacticities, syndiotactic/atactic isomers (sPS/aPS), have been systematically studied to reveal the composition dependence of the blend morphologies, i.e., sPS lamellar structure and aPS diluent segregation, developed after isothermal crystallization. To reveal the molecular weight effect of the aPS diluents, four different of aPS were used to prepare blends with various compositions. After being melt crystallized isothermally at 250 °C, all blends were investigated by means of POM, WAXS, and SAXS as well as SEM and TEM to reveal the spherulitic and lamellar morphologies developed.

     

TBP从盐酸溶液中萃取锡的稀释剂效应

TBP从盐酸溶液中萃取Sn~(4+)时,其稀释剂的影响不仅与稀释剂的性质有关,而且与盐酸浓度,萃取剂浓度,初始水相中锡的浓度等有关。只有[HCl]<6mol/L,[TBP]<40%,[Sn~(4+)]_(in)<1.5g/L时,才能排除这些因素的影响,因为这时各种稀释剂对Sn~(4+)的分配比D_(Sn~(4+))随这些因素的变化趋势相一致。在TBP-SnCl_4-HCl体系中,对于非极性类稀释剂,若按D_(Sn~(4+))的大小来排列,则烷烃类(环己烷、正己烷、正庚烷)>芳烃类(苯)>卤代烃类(四氯化碳),且可用稀释剂的极化率与摩尔体积等因素来解释;对于极性类有接受电子基团的稀释剂,则硝基苯>1,2-二氯乙烷>氯苯>氯仿,可用稀释剂的偶极矩、介电常数、溶解度参数或粘度等物性参数来解释其规律。     

液-液萃取法从湿法磷酸中脱氟制饲料磷酸氢钙

发现三辛胺(TOA)萃取氟时,在氯仿(CLF)、二氯乙烷稀释剂中有很强的溶剂效应,可使分配比D_F增大约8.8倍,分离系数β_(F/P_2O_5)增大约66倍。研究了该体系的萃取行为和性质,考察了各种因素对萃取性能的影响,从而确定了分离的最佳工艺条件:298K;平衡时间约120s;溶剂配比为TOA∶CLF∶煤油=1∶2∶2(v/v);相比为1;三级逆流萃取。反萃取条件为:313K;碱液浓度1～2kmol/m~3;单级反萃取。脱氟磷酸与Ca(OH)_2中和反应4小时,产品磷酸氢钙(CaHPO_4·2H_2O)中F<0.15%。     

Role of complement in demyelination in vitro by multiple sclerosis serum and other neurological disease sera

Multiple sclerosis (MS) sera can demyelinate and cause selective cellular changes to organ cultures of rodent CNS which suggests possible immunoglobulin involvement. The complement dependence of this serum action was investigated using complement-inactivating agents and radiolabelled rat cerebellar cultures. After heat inactivation at 56 degrees C, the in vitro effects of MS, chronic relapsing experimental allergic encephalomyelitis (cr-EAE) and Guillain-Barré syndrome (GBS) sera were severely reduced or eliminated as measured by radiolabel release. On introducing a source of fresh complement, the cr-EAE and GBS serum effects were largely restored whereas MS serum effects remained suppressed. Inactivation of serum complement with mercaptoethanol and Zymosan was associated with marked reduction in serum myelinotoxicity; some restoration of in vitro effects was possible on adding fresh complement although this occurred to a greater extent with cr-EAE and GBS than with MS sera. Inactivation of the alternative complement pathway brought a limited reduction in MS serum activity in vitro which was not restored with fresh complement. It is concluded that complement is involved only to a limited extent in MS serum myelinotoxic effects and that MS serum effects in vitro are due to several components of which thermolabile substances make a significant contribution and are as yet uncharacterised.     

小儿清热止咳分散片的填充剂与崩解剂筛选

目的为了制备中药分散片,以小儿清热止咳糖浆方剂为模型药物筛选中药分散片的填充剂和崩解剂。方法以抗张强度、吸湿性和压缩功作为选择填充剂的依据,以吸水性实验、溶胀度实验、空白片崩解时限和加入质量分数为50%浸膏的片剂崩解时限为选择崩解剂的依据。测定发泡量和产气量作为选择泡腾崩解剂的依据。结果综合以抗张强度、吸湿性和压缩功大小,选择乳糖作为分散片的填充剂。溶胀性能优劣顺序是:CMS-Na>L-HPC(信越)>PVPP>MCC101>MCC301>L-HPC(国产)>MCC302>MCC102>滑石粉>干淀粉;吸水性能优劣顺序是:L-HPC(信越)>L-HPC(国产)>CMS-Na>PVPP>MCC302>MCC102>MCC301>MCC101>浸膏;单独使用微晶纤维素或超级崩解剂达不到分散片的质量要求,联用微晶纤维素和超级崩解剂,可以达到分散片质量要求。结论中药分散片的崩解剂可以采用超级崩解剂和微晶纤维素的混合物,泡腾崩解剂选用酒石酸和碳酸氢钠,其摩尔比为1.0∶0.8。     

全血中锰的石墨炉原子吸收光谱直接快速分析法

目的建立全血中锰的直接快速石墨炉原子吸收光谱分析方法。方法硝酸和TritonX-100作为样品混合稀释液,全血用混合稀释液消解乳化后,采用氘灯校正背景,石墨炉原子吸收光谱法自动进样测定。结果方法的线性范围为0～3.0μg/L,相关系数为0.9992,RSD为1.1%～7.7%,加标回收为93.7%～101.0%,方法检出限为0.25μg/L。结论该法准确度、精确度良好,样品不需要消化,污染小,是一种简单、快速、可行的测定全血锰的方法。     

碘伏稀释液冲洗腹腔预防术后腹腔感染的效果观察

目的:观察碘伏稀释液冲洗腹膜腔预防术后腹腔感染的效果。方法:选择41例伴有急性弥漫性腹膜炎的急腹症手术患者,关腹前应用碘伏生理盐水混合液彻底冲洗腹腔直至冲洗液澄清为止。结果:41例患者无1例出现术后腹腔内感染。结论:碘伏稀释液冲洗腹腔可有效降低手术感染发生率。     

丁羟氨酯丙烯酸树脂的性能及结构

比较了以甲基丙烯酸甲酯（MMA）和苯乙烯（St)为稀释剂制备的丁羟氨酯丙烯酸树脂固化物的性能与结构，MMA作为稀释剂的体系有更高的强度；DSC表明前一体系有更高且更宽的玻璃化转变温度；SEM表明前者的相分离显著得多。