Purify Deacetylmycoepoxydiene with Solventing-out Crystallization

为考察溶析结晶纯化去乙酰真菌环氧乙酯的效果,研究了不同的溶剂、反溶剂含量和导入方式对去乙酰真菌环氧乙酯结晶的影响.在静态结晶实验的基础上,通过设计正交实验l9(34)研究动态结晶过程中各因素对去乙酰真菌环氧乙酯收率和纯度的影响.结果表明:有效地控制反溶剂含量及其导入方式可以提高晶体的纯度和收率并影响晶体的形态.去乙酰真菌环氧乙酯动态结晶最佳条件:结晶温度为15℃,溶剂-反溶剂体积比(丙酮-水)为2∶3,反溶剂流加时间为3 H.In order to purify deacetylmycoepoxydiene(DAM)using solventing-out crystallization technique,the optimal conditions of crystallization were investigated by orthogonal design,and the recovery and purity of DAM were used as major evaluating contents.The results showed that the shapes of DAM crystal were influenced by different solvents,the recovery and purity of DAM were also influenced by the volume of anti-solvent and the way it was conducted.The optimal parameters are described as follows:crystallization temperature is 15 ℃,V(acetone)∶V(water)=2∶3,the flowing time of anti-solvent is 3 hours.国家海洋863项目(2007AA091503

三个鲫品系DNA含量的比较研究

采用流式细胞术 (FCM)对红鲫、彭泽鲫、异育银鲫进行红血球DNA含量的检测分析比较 ,以鉴定它们的倍性。结果显示 ,红鲫红血球的DNA含量是 3 0pg ,彭泽鲫是 4 7pg ,异育银鲫是 4 8pg。显而易见 ,彭泽鲫的DNA含量是二倍体红鲫的 1 57倍 ,异育银鲫的DNA含量是红鲫的 1 6倍。采用肾细胞直接制作染色体的方法进行红鲫、彭泽鲫、异育银鲫的染色体倍性鉴定 ,结果红鲫的染色体数目是 10 0 ,为二倍体 (2n =10 0 ) ,彭泽鲫的染色体数目是 162 ,为三倍体 (3n =1

Design of NMR transmit pulse waveform based on FPGA

基于任意波形发生器的原理,采用ddS(dIrECT dIgITAl SynTHESIS)技术,以单片机控制芯片STC89lE51和fPgA芯片XC5VfX70T为基础进行硬件和逻辑设计,使用ISE10.1和MOdElSIM软件编写脉冲波形发生器的各个子模块和测试模块,利用上位机软件或者键盘模块进行设置,改变波形频率和相位,最终产生核磁共振谱仪所需的调频调相波形数据。仿真结果表明,该方案产生的信号波形可灵活实现频率和相位的更改,波形性能良好,对于核磁共振谱仪发射脉冲波形的设计提供了可靠的方法和思路。The hardware and logic design based on MCU control chip STC89LE51 and FPGA chip XC5VFX70T combines the principle of the arbitrary waveform generator with DDS(direct digital synthesis) technology.The sub-modules of pulse waveform generator and test modules are designed by ISE10.1 and Modelsim.Using the PC software or keyboard to set the frequency and phase of waveform,the ultimate frequency modulation and phase modulation waveforms data required by the NMR spectrometer can be generated.The simulation results show that the signal waveform designed by the program can have a good performance in the change of frequency and phase,providing reliable methods and ideas for the design of the transmit pulse waveform in the NMR spectrometer.国家自然科学基金(11175149)资助项

Preparation of Deacetylmycoepoxydiene with Reversed Phase Chromatography

研究不同条件下反相柱层析对去乙酰真菌环氧乙酯分离纯化的影响.通过rP-18中压柱层析对从红树林内生真菌拟茎点霉(PHOMOPSISSP.)A-1-2-3诱变后突变株g1-1固体发酵提取物中的去乙酰真菌环氧乙酯进行了纯化精制.对rP-18柱层析纯化去乙酰真菌环氧乙酯操作条件进行了考察,使去乙酰真菌环氧乙酯的含量从28%左右提高到81.5%左右,回收率大于90%.采用rP-18直接洗脱,溶析结晶,重结晶,结晶残液rP-18分步洗脱的总工艺路线,去乙酰真菌环氧乙酯的总回收率为87.7%,产品最终纯度达到99%以上.The effects on purification of deacetylmycoepoxydiene(DAM) in different conditions were studied.Preparation of DAM from the crude extract of fermentation of strain G1-1,a mutant strain of mangrove endophytic phomopsis sp.A-1-2-3,was conducted using C18-silica gel reversed phase chromatography at moderate pressure.In the process,the operating conditions of C18-silica gel chromatography were studied experimentally,then the purity of DAM reached about 81.5% from about 28% in the crude extract,and the recovery of DAM was over 90%.The whole process of preparation was as follow: direct elution with RP-18,solvent-out crystallization,recrystallization and segment elution of residue of crystallization with RP-18.Through the whole process flow,the general recovery of DAM was 87.7%,and the purity of DAM reached 99% or higher.国家海洋863项目(2007AA091503)资

高寒退化与未退化草甸土壤下匍匐茎鹅绒萎陵菜的克隆生长特征的比较

通过鹅绒萎陵菜的野外移栽试验 ,分析了在矮嵩草草甸土壤和退化草甸土壤下该种植物的克隆繁殖特征 .结果表明 ,在母株产生的匍匐茎数量、母株高度和叶片大小在两类不同土壤下没有明显差异 .母株叶片数、匍匐茎的粗度、匍匐茎长度以及间隔子的长度有较明显的差异 .在退化草甸土壤中母株叶片较多 ,匍匐茎长度和间隔子长度明显较长 ,匍匐茎直径也明显较大 .在退化草甸环境中 ,由于土壤养分相对较缺乏 ,鹅绒萎陵菜可能通过增加母株叶片的数量 ,尽可能多地积累光合产物 ,来保证匍匐茎的生长 ,匍匐茎也以增加粗度和增加长度来尽量增强其觅食能力 .鹅绒萎陵菜在生物量投资分配上也表现出一定的差异 .与退化草甸土壤环境相比 ,在未退化草甸土壤中 ,鹅绒委陵菜克隆母株和分株的生物量均明显偏向地下部分 (根系 )的投资 ,以期从土壤中吸收更多的养分 ,从而最终提高子株的成活

Technology of Pretreating Fermentation Broth of Deacetylmycoepoxydiene

为了降低去乙酰真菌环氧乙酯发酵液粘度,改进过滤效果,考察了β-葡聚糖酶对去乙酰真菌环氧乙酯发酵液粘度的影响,并进一步研究了不同类型的絮凝剂对发酵液过滤速度、沉降率、有效过滤体积和去乙酰真菌环氧乙酯含量的影响.通过正交试验,确定了非离子型聚丙烯酰胺的最佳絮凝工艺条件,应用统计学手段获得了最佳酶促反应时间和酶用量.结果表明,β-葡聚糖酶和非离子型聚丙烯酰胺的联合使用,可使滤速提高80%,有效过滤体积增加50%,保证了去乙酰真菌环氧乙酯的发酵量.In order to lower the viscosity of deacetylmycoepoxydiene fermentation broth and improve the effect of filtering,the impact of β-glucanase on the viscosity of DAM fermentation broth was studied.The effects of different types of flocculants on filtration rate of fermentation-broth,sedimentation rate,the effective filter volume and concentration of DAM were further studied.Through orthogonal test,the optimal flocculation conditions of the non-ionic flocculants were obtained,and enzymatic reaction time and enzyme dosage of β-glucanase were determined by statistical methods.The results show that the filtration rate is increased by 80% and effective filter volume is increased by 50% through the joint use of the β-glucanase and non-ionic flocculants.It ensures the fermentation volume of DAM.国家海洋863项目(2007AA091503)资

Preparation and Characterization of Bipolar Membranes Modified by Functionalized Multiwalled Carbon Nanotubes Loaded with Fe~(3+)

分别用未功能化的多壁碳纳米管(MWCNTs)、羟基化多壁碳纳米管(MWCNTs-OH)、羧基化多壁碳纳米管(MWCNTs-COOH)、磺酸基化多; 壁碳纳米管(MWCNTs-SO_3H)改性羧甲基纤维素钠(CMC)-聚乙烯醇(PVA)/壳聚糖(CS)-聚乙烯醇双极膜(BPM)的阳离子交换膜层; 。采用力学性能分析、接触角测定、电流密度-槽电压曲线等对改性前后双极膜的性能进行表征,并测定了改性前后双极膜中Fe~(3+)的流失量。结果表明,; 经功能化多壁碳纳米管改性后,双极膜的亲水性和力学性能得到了显著提高。功能化多壁碳纳米管和Fe~(3+)对催化中间界面层水解离有协同作用,大大提高; 了中间界面层水解离效率,降低了双极膜的膜阻抗和槽电压。此外,改性后双极膜中Fe~(3+)的流失量有了明显的下降,从而保持了双极膜结构和催化水解离; 性能的稳定性。The cationic exchange layers of the carboxymethyl cellulose (CMC)-; polyvinyl alcohol (PVA) /chitosan (CS) -polyvinyl alcohol bipolar; membranes (BPM) using glutaraldehyde as crosslinker and ferric chloride; as modifier, were modified by multi-walled carbon nanotubes (MWCNTs),; hydroxylated multi-walled carbon nanotubes (MWCNTs-OH), carboxylated; multi-walled carbon nanotubes (MWCNTs-COOH) and sulfonated multi-walled; carbon nanotubes (MWCNTs-SO_3H), respectively. The mechanical; properties, contact angle and electric current density-cell voltage; curve as well as the Fe~(3+) loss amount of the CMC-PVA/CS-PVA BPMs; before and after modification were compared. The experimental results; show that after modification by functionalized multi-walled carbon; nanotubes, both the hydrophilicity and mechanical properties of the; bipolar membrane are significantly improved. The functionalized; multi-walled carbon nanotubes and Fe~(3+) have a synergistic effect on; promoting water splitting in the intermediate layer, thus the water; splitting efficiency is greatly improved, and the membrane impedance and; cell voltage of bipolar membrane are reduced. In addition,; functionalized multi-walled carbon nanotubes existed in the bipolar; membrane are beneficial for retention rate of Fe~(3+) in BPMs during; electrolysis, and then to maintain the stability of the structure and; catalytic performance for water splitting of the BPMs.福建省科技厅重点项目; 福州市科技局项目; 福建省自然科学基金资助项