海人酸对大鼠海马损毁的技术研究

文章就海人酸对大鼠海马进行化学性损毁的剂量，坐标选择以及损毁的特异性等问题进行了探讨。结果表明海人酸对海马锥休细胞有较特异性的损毁，而不影响输入纤维和这路纤维；0.5ug海人酸损毁的特异性0.3ug海人酸损毁的差，LR2.0mm与LR2.5mm的损毁结果很相似。     

Synthesis of Polyketone STCO Promoted by Rare Earth Catalyst

To lower the cost of polyketone synthesis, rare earth coordinate catalyst was introduced to the copoiymerization of carbon monoxide (CO) and styrene (ST) to synthesize aliphatic polyketone STCO. The catalytic system was composed of rare earth neodymium acetate, yttrium acetate, 2,2'-bipyridine, p-toluensulfonic acid, cupric p-toluensulfonate, and 1,4-benzoquinone. The catalyst and the copolymer were characterized by infrared spectrum and X-ray photoelectron spectrosco py respectively. The effects of each component of catalytic system and the kinds of rare earth acetates on catalytic activity of copoiymerization were investigated. The results show that the proposed rare earth has distinct catalytic activity in the copoiymerization of CO and ST and the maximum activity can reach 303.3 gSTCO/(mol·h).     

沉水植物在静止水体中对悬浮固体的作用

水中悬浮固体会影响沉水植物正常的生长，沉水植物反过来也会影响水中悬浮固体的浓度和沉降。实验研究了两种典型的沉水植物——轮叶黑藻和亚洲苦草在静止水体中对悬浮固体的作用，并与空白组进行了比较。结果表明：轮叶黑藻在一定条件下可明显降低水中悬浮固体的浓度，亚洲苦草则效果较差，另外沉水植物的种植都可以有效降低底部沉积物的量。     

Optimization of callus cultures at Echinacea purpurea L. for the amount of caffeic acid derivatives

BackgroundIn order to produce an effective callus in Echinacea purpurea L.; determination of the explant type and growth regulators that best respond to callus induction and the optimization of the culture conditions to increase the amount of caffeic acid derivatives (CADs) in the obtained callus. CADs contents of callus cultures of E. purpurea were evaluated by establishing an effective callus induction system in vitro.ResultsVarious medium containing different growth regulators were tested using leaf, petiole, cotyledon and root as the explants. The best callus development was achieved in MS medium with 1.0 mg l⁻¹ 2,4-D + 2.0 mg l⁻¹ BAP in leaf, 1.0 mg l⁻¹ NAA + 0.5 mg l⁻¹ TDZ in petiole, 2.0 mg l⁻¹ NAA + 1.0 mg l⁻¹ TDZ in cotyledon and 0.5 mg l⁻¹ NAA + 0.5 mg l⁻¹ BAP in roots. Upon optimisation of callus growth, each type of explant was cultured for 4, 6, 8 and 10 weeks in medium for the analyses of caftaric acid, chlorogenic acid, caffeic acid and chicoric acid contents. The highest amounts of caftaric acid (4.11 mg/g) and chicoric acid (57.89 mg/g) were found from petiole explants and chlorogenic acid (8.83 mg/g) from root explants at the end of the 10-week culture time.ConclusionsAs a result of the present study, the production of caffeic acid derivatives was performed by providing the optimization of E. purpurea L. callus cultures. Effective and repeatable protocols established in this study may offer help for further studies investigating the production of caffeic acid derivatives in vitro.How to cite: Tanur Erkoyuncu M, Yorgancilar M. Optimization of callus cultures at Echinacea purpurea L. for the amount of caffeic acid derivatives. Electron J Biotechnol 2021;51. https://doi.org/10.1016/j.ejbt.2021.02.003.     

大豆蛋白酶解工艺条件的研究

采用 As 3.350酸性蛋白酶对豆饼粉进行水解工艺条件的研究 .实验结果表明 ,原料预处理最佳工艺条件为 :5% HCl,豆饼粉加水比为 1∶ 4,90℃处理 3.5 h;酶解最佳条件为 :每克原料的酶浓度为 60 0 0 u,p H为 3.0 ,温度为 45℃ ,时间为 9h.预处理前过 70目筛 ,加入 2× 1 0 -3mol/ L的Ca Cl2 ,并加以搅拌 ,可使氨基酸态氮生成率达到 70 % ,氨基酸态氮含量达到 0 .9g/ l0 0 m L左右     

聚乳酸行业的发展现状及发展趋势

聚乳酸作为一种新型材料,具有优良的物理性能、良好的生物相容性及生物降解性,因而被广泛地应用于日用、医用等领域.对聚乳酸的生产技术、应用进行了论述,对聚乳酸行业的发展现状进行了详细的描述;就目前而言,受原料及聚合技术的影响,聚乳酸真正替代石油基的塑料制品还需要很长的路要走.     

实用新型厌氧运送盒的研究与设计

目的：为医疗机构研究设计一种新型的厌氧运送盒,用于运送厌氧固体标本,使标本处于厌氧环境。方法用高度透明、密封性能强的材料制备密封盒。盒内放置临床标本,设置插管等容器,通过冷触媒法在密封盒体内发生化学反应,从而消耗氧气。结果根据临床情况,研制出不同体积的运送盒,放入不同体积的标本,加入不同用量的化学药品、催化剂和指示剂。这种密封盒体,通过化学反应达到厌氧环境。结论此新型厌氧运送盒设计新颖,制作程序简捷,密封效果好,药物反应可控,厌氧指示科学,使用方便。     

汽车动力铅酸电池的充放电辅性及均衡管理技术的研究

动力电池组中单体电池间的差异使之具有不同的充放电特性，电池组在充放电循环过程中又增加了单体电池的不一致性，导致某些单体电池过充过放电现象的发生，使得整个电池组的性能及使用寿命下降。所以为了延长电池组的使用寿命，需对电池组进行均衡充放电。     

复合固体超强酸S2O8^2-／ZrO2-SnO2的制备及催化合成己酸异戊酯的研究

合成了复合固体超强酸S2O8^2-／ZrO2-SnO2,研究了SnO2的最佳添加量,并将其应用于催化合成己酸异戊酯的反应,考查了最佳反应条件．SnO2的最佳添加量为2．0％,最佳反应条件为0．10mol己酸使用1．0g复合固体超强酸催化剂,醇酸摩尔比2．0,反应时间为2．5h,己酸的酯化率可达96％以上,而且不污染环境．     

固态氨基酸的THz时域光谱研究

利用太赫兹时域光谱室温下对手性对映体D 酪氨酸、L 酪氨酸、外消旋化合物DL 酪氨酸和D 色氨酸、L 色氨酸、外消旋化合物DL 色氨酸在 0 1～ 2 0THz频谱范围内进行了光谱测量 .结果表明 ,所研究的氨基酸在此波段有特征吸收峰 ,THz时域光谱能够鉴别对映异构体和他们的外消旋化合物 .