Effect of Decrystallization of Cellulose on Adsorbing Cellulase

为探讨解结晶处理提高酶水解效率的机理,对比研究了高结晶度的微晶纤维素(MCC)和低结晶度的解结晶微晶纤维素(D-MCC)对纤维素酶的吸附过程。结果发现:酶吸附平衡后,样品的XPS和FT-IR分析表明纤维素酶通过酶蛋白的氨基(—NH_2)与纤维素分子链上的羟基(—OH)之间以氢键(C—OH…NH)力吸附在MCC上;相同条件下得到的MCC和D-MCC吸附率曲线的差异表明,底物结构的改善比提高温度更能提高酶吸附率;比较纤维素酶对MCC和D-MCC在35℃下的吸附动力学可知,通过降低底物的结晶度可促进酶吸附,刚性结构的MCC更满足准一级动力学的假设,D-MCC表面结构相对松散,其吸附过程需进一步分析,以得到更适合的动力学方程。The cellulase adsorbed and formed enzyme-substrate( ES) compound is a key step in the process of enzymatic hydrolysis. Through the comparison of cellulase adsorbed on two substrates: microcrystalline cellulose( MCC) with high degree of crystallinity and decrystallization microcrystalline cellulose( D-MCC) with low degree of crystallinity,it was found that,in the XPS wide scan patterns of adsorption equilibrium MCC,a new absorption peak of nitrogen element( 399. 06 e V) was observed. The fitting method is adopted to treat the strong peak of XPS-O1 s,and the binding energy of this new peak was only 530. 53 e V. In the infrared absorption range of 3050- 3550 cm~(- 1),the absorption intensity of OH group decreased with extending adsorption time on cellulose. The above results proved that new hydrogen bonds( C—OH…NH) between the protein amino( —NH_2) and cellulose molecule chain( —OH) were generated during the cellulose adsorption process. From the comparison of the adsorption rate curves between MCC and D-MCC,the decrystallization method to improve cellulase adsorption was more effective than enhancing the temperature. From the comparison of adsorption kinetics between MCC and D-MCC at 35℃,it was indicated that a reduction of cellulose crystallinity was positive for adsorption rate. MCC with rigid surface was fit for the first-order kinetic hypothesis. D-MCC with flexible surface was not suitable for the first-order kinetic. A more suitable kinetic hypothesis should be investigated in the future.国家自然科学基金-广东自然科学基金联合基金重点项目(U0733001

台湾海商法的变革及其特色

台湾海商法的变革及其特色李景禧，林光祖台湾海商法源于1929年公布的国民党《海商法》，共八章174条。1962年，为适应台湾地区海商经济发展的需要，台湾当局对海商法进行全面修改，增为十章194条。同时，废止旧海商法施行细则并陆续公布船舶法、船舶登记法..

台湾“民法”的司法运作

本文摘自李景禧教授与林光祖教授合著的《台湾民商事法研究》(法律出版社1996年版),文字略有调整。李景禧(1912—1995),1933年毕业于朝阳大学,留学于日本东京大学;回国后,历任朝阳大学法律系教授,民国时期“最高法院”推事(法官),南京《法律评论》主编,福建学院法律系教授兼系主任,厦门大学法学院教授;生前曾任中国法学会名誉理事,中国法学会民法学经济法学研究会顾问,中国消费者协会理事,第六、七、八届全国人大代表,民革中央委员。李景禧教授是我国法学界的老前辈,知名的民法学者,对我国法学教育事业和社会主义法制建设做出了突出的贡献。本刊特发此文,以示纪念

Discussion on effective enzymatic hydrolysis of cellulose

纤维素酶解可为生物质基的能源与化工品开发提供必需的水溶性还原糖。实验以浓磷酸解结晶处理结合纤维素酶-β-葡萄糖苷酶混合酶液的协同酶解,构建了一种高效酶解方法。实验结果表明,酶水解的最佳条件为:酶液质量浓度为0.062 5 Mg/M l,底物质量浓度为12.5 Mg/M l,P H为4.8缓冲溶液,酶解温度为50℃,转速为120 r/MIn。解结晶MCC结合协同酶解方法作用120 H和解结晶麦草结合协同酶解方法作用120 H,产物得率均得到大幅提高。Enzymatic hydrolysis can provide necessary soluble reducing sugars for biomass based energy and chemicals.An effective enzymatic hydrolytic method is established by using the concentrated phosphoric acid to decrystallize the microcrystalline cellulose( MCC) and wheat straw,and cellulose to mix with β-Glucosidase.The optimal enzymatic hydrolysis conditions are shown as follows: 0.062 5 mg / m L of cellulose,12.5 mg / m L of substrate,p H 4.8 of citric acid buffer solution,50℃ of enzymolysis temperature and 120 r / min of shaking speed.The yields are both greatly improved for decrystallization of MCC / enzymolysis and decrystallization of wheat straw / enzymolysis for 120 hours.中山市科技技术项目(2014A2FC333); 电子科技大学中山学院科研团队培育项目(412YT02

Design of tracking system for marine moving object

为实现对海上运动目标的实时跟踪,克服跟踪效果易受到严重遮挡影响的缺点,建立了一套实时跟踪系统,并且结合目标的运动信息与新的模型更新策略,对均值漂移与卡尔曼滤波器相结合的跟踪算法做出了改进。当运动船只被遮挡的比例较大时,先用估计出的目标速度矢量更新卡尔曼滤波器,并用相应的模型更新策略更新目标模型以提高模型相似性度量的精确性,再单独利用滤波器进行跟踪,取得了较好的跟踪效果。实验结果表明,该系统可以较好地实现海上运动目标的跟踪,并且改进后的算法具有良好的实时性和鲁棒性。To accomplish the real-time tracking for the marine moving object and overcome the defect of the susceptibility to severe occlusion,a set of real-time tracking system for the moving object at sea is designed.In virtue of the motion information and a new kind of model update strategy,some improvements are made for tracking algorithm combining the mean-shift with Kalman filter.When the moving vessel is largely blocked,Kalman filter is updated by the prior estimated velocity vector,and the accuracy of model similarity measurement is improved by utilizing the model update strategy,then the filter is exploited to implement tracking.The algorithm achieved good tracking effect.Experimental results show that the system implement marine moving object tracking with good real-time performance and robustness

Fast and effective method for video mosaic

针对现有的视频图像序列拼接方法处理速度慢的问题,提出一种基于Surf特征的快速有效的拼接算法。该算法用鲁棒性强且计算性能优越的Surf算子取代传统的SIfT算子进行特征点提取;在特征点匹配方面,提出了一种基于哈希映射和双向最近邻距离比的匹配算法,可以快速有效地获得特征点间的对应关系。为了消除由于运动物体干扰带来的误匹配,采用随机采样一致性(rAnSAC)方法来消除外点确保匹配的有效性,再通过最小二乘法估计视频帧之间的全局运动参数,最终拼接形成全景图。实验结果表明,该拼接算法快速有效,鲁棒性强,具有较高的使用价值。As the existing methods for video mosaic take high computational costs,a fast and effective algorithm based on SURF feature for video mosaic is proposed.The algorithm uses SURF method with strong robustness and superior performance to extract feature instead of SIFT.At the aspect of feature matching,a novel matching scheme based on hash mapping and bidirectional nearest neighbor distance ratio is presented,which can quickly and effectively obtain the relationship between the features.In order to exclude the error matchings,a RANSAC technique is applied to eliminate outliers to ensure effectiveness of the matched pairs,and then the global motion parameters are estimated by a least-squares solution,finally panorama from video sequence is achieved using the parameters.Experimental results show that the method with strong robustness performs fast and effectively and has highly valuable in practice

从信息不对称角度看境外机构投资者可能带来的负面影响

实行境外机构投资者制度是我国谨慎对外开放证券市场的重要步骤之一。但如果考虑到信息不对称的问题,则境外机构投资者可能产生的负面影响也是不容忽视的。主要是因为:首先,由于投资者与机构投资者之间、机构投资者与上市公司之间存在双重委托代理关系,结果可能导致机构投资者行为的非理性化。其次,由于新兴市场国家的金融市场还很不完善,境外机构投资者因存在着信息不对称而难于发挥其对新兴市场的积极作用。所以境外机构投资者的进入未必能促进新兴市场经济的增长和资源的有效配置;境外机构投资者的某些交易策略可能影响新兴市场国家证券市场的稳定。为此,就如何进一步完善我国的境外机构投资者制度,更好地发挥境外机构投资者对我国证券市场及经济发展的积极作用提出若干政策建议

Preparation of potassium diformate by methyl formate and potassium hydroxide

联系人：李清彪. 第一作者：詹国武（1986—），男，学士.[中文文摘]本研究采用甲酸甲酯、氢氧化钾、甲酸为原料，一步反应制备二甲酸钾。系统地考察了影响产品收率的主要因素，优化了工艺条件，结果表明，当n(MF)/n(KOH)=1.20，n(HCOOH)/n(KOH)=1.44，反应时间为30min，反应温度为55℃时，二甲酸钾产品收率可达 98.8%。产品经红外光谱分析及成分测定，符合质量标准。[英文文摘]In this study, methyl formate, potassium hydroxide and formic acid were used as raw materials for one-step synthesis of potassium diformate. The main factors affecting the quality and yield of product were investigated. The optimal conditions for reaction were: molar ratio of MF to KOH 1.20:1, molar ratio of HCOOH to KOH 1.44:1, reaction time 30 min and reaction temperature 55℃. The product met the quality standard of potassium diformate after infrared spectrum analysis and composition determination.厦门大学创新性实验计划资助项

丙烯酸酯和甲基丙烯酸酯基团转移共聚研究

研究了三种丙烯酸酯分别和四种甲基丙烯酸酯的基团转移共聚，用１ＨＮＭＲ法测定共聚物组成，扩展的ＫｅｌｅｎＴｕｄｏｓ法测定竞聚率，结果为γＭＡ＝９２３、γＭＭＡ＝００６；γＥＡ＝１４１５、γＭＭＡ＝００１；γＢＡ＝７５１、γＭＭＡ＝００２；γＭＡ＝１４４１、γＥＭＡ＝００１；γＭＡ＝１３９６、γＢＭＡ＝０２３；γＭＡ＝８６６、γｉＢＭＡ＝００８，表明基团转移聚合同阴离子聚合有明显的相似之处