HDI三聚体和偶联剂对纸质文物加固保护的研究

用传统的高分子树脂对纸质文物进行加固保护取得了一定的效果 ,但由于高分子树脂的渗透、润湿性能较差 ,容易增加纸张光泽 ;会产生内应力加速纸张老化等问题。针对这个问题 ,本文研究了一种纸质文物加固保护的新方法 ,采用低分子预聚物 HDI三聚体对纸张聚氨酯化 ,并用偶联剂 KH-5 5 0协同处理。通过正交试验分析了处理工艺中各种因素对纸张拉伸干强度的影响 ;并通过对拉伸湿强度、光泽度的测试和酸碱加速老化、干热加速老化等试验验证了 HDI三聚体和 KH-5 5 0对纸质文物的加固保护作用 ,并用 DSC和扫描电镜进行了分析。试验表明 ,这种处理方法在保护纸张原有质感的同时提高了纸张强度 ,降低了纸纤维的吸湿性 。

终极控制权、大股东制衡与信息披露质量

本文从第二类代理问题和特殊资产保护出发,基于终极控制权,探讨控股股东和其他大股东以及大股东制衡机制对上市公司信息披露战略及信息披露质量的影响。实证研究表明:(1)虽然控股股东控制权比例越高的上市公司,信息披露显得越可靠和及时,但控股股东无意于提升信息披露的相关性。(2)控股股东现金流权比例越高,即其特殊资产卷入程度越高,越有可能卷入信息操纵。提高信息披露的可靠性和及时性,但同样无意于提升信息披露的相关性。(3)其他大股东可能阻碍控股股东操控信息披露,其他大股东持股比例越高,越有可能对信息披露以及信息披露的可靠性和及时性产生负面作用。(4)其他大股东制衡度与信息披露指数、信息披露可靠性和及时性之间表现为显著的U型关系。

Effects of Different Preservation Methods on Physicochemical Property of Marine Pathogen Vibrio anguillarum

Freeze-drying,continuous passage and ultra-low temperature cryopreservation are often used to preserve pathogens.In this study,Vibrio anguillarum was rejuvenated by intramuscular infection as the initial strain.The difference between cells preserved with different preservation methods and their initial strains were compared with physiological and biochemical methods and through antibiotics resistance analysis.The composition of protectants for freeze-drying V.anguillarum was optimized.We found that the optimal composition of protectants was 8% of trehalose,12% of skim milk,8.0% of lactose,2.0% of sodium citrate,12.0% of serum and 8.0% of mannitol.The indexes of lysine decarboxylase and urease changed after continuous passage.The urease reaction changed after freeze-drying and freeze-thawing,but the reaction can be restored to the initial after freeze-drying.Based on the antibiotics resistance analyses,the sensitivity of V.anguillarum to different drugs including rifampicin,erythrocin,furazolidone,ceftazidime,lomefloxacin,gentamycin,azithromycin,doxycycline,ampicillin,co-trimoxazole and cefoperazone changed after different treatments,and some of these changes can be restored to the original through activation culture.In sum,compared with cryopreservation and continuous passage,the freeze-drying is more sustainable for the long-term preservation of V.anguillarum,which showed a better effect in maintaining the original characteristics of pathogen.

Chicken Embryo Inhibition Test of Recombinant Freeze-drying Chicken Interferon against Newcastle Disease Virus( NDV) F_(48)E_(10)

The paper was to study the inhibitory effect of recombinant freeze-drying chicken interferon against Newcastle disease virus （NDV） F48E10. Nine-day-old chicken embryos were inoculated with recombinant freeze-drying chicken interferon via allaotoic sack, while 10-day-old chicken embryos were inoculated with NDV F48E10, and in vivo protective efficacy of interferon on chichen embryos was studied. The results showed that the recombinant freeze-drying chicken interferon at the dose of 1.28 mg/embryo reached the protection ratio of 90% on chicken embryo infected by F48E10.

红茶菌优势微生物冻干菌粉的制备

选用脱脂奶粉、甘油、蔗糖、海藻糖等冻干保护剂筛选对红茶菌中优势微生物醋酸菌和酵母菌的最佳冻干保护剂。结果表明,4种保护剂都有很好的作用效果,Y_1蔗糖效果最好,其次为海藻糖;Y_2为脱脂奶粉效果最好,其次为蔗糖;Y_3效果最好的为脱脂奶粉和蔗糖,活菌率可以达到17.4%和16%;同样Y_4也是蔗糖保护的效果略好于其他3种,醋酸菌AC2为蔗糖效果最好,活菌率为12.8%,其次为脱脂奶粉、海藻糖和甘油。另外,10%的蔗糖作为保护剂冻干效果要明显好于5%的蔗糖。使用不同组合的冻干的菌粉来发酵茶糖水,结果发现冻干菌粉发酵的红茶菌中,其中5个组合口味较好。