用消去法推求原子谱项

提出了确定复杂组态的Ｓｌａｔｅｒ函数和原子谱项的程序化方法。运用Ｐａｓｃａｌ语言编制了计算程序，利用本程序可准确地导出等效组态ｓ＾Ｎ，ｐ＾Ｎ，ｄ＾Ｎ，ｆ＾Ｎ，ｇ＾Ｎ，ｈ＾Ｎ，ｉ＾Ｎ，ｋ＾Ｎ，ｌ＾Ｎ，ｍ＾Ｎ，ｎ＾Ｎ，ｏ＾Ｎ，ｑ＾Ｎ，ｒ＾Ｎ，ｔ＾Ｎ，ｕ＾Ｎ，ｖ＾Ｎ，ｗ＾Ｎ，ｘ＾Ｎ，ｙ＾Ｎ，ｚ＾Ｎ的Ｌ－Ｓ耦合谱项和Ｓｌａｔｅｒ函数。迄今为止，还未见国内外文献报道过。     

Existence and approximation of solutions for discontinuous functional differential equations

In this paper existence of solutions of initial value problems for discontinuous functional differential equations is investigated firstly. By applying the method of upper and lower solutions, which may be discontinuous, some existence results of extremal solutions are obtained. Furthermore, we also develop a monotone iterative technique for obtaining extremal solutions which are obtained as limits of monotone sequences.     

基于JSP和Android的歌手竞赛信息交互系统设计

为了打造校园歌手选拔的线上“生态系统”,完成线上与线下的互动闭环,提出一种基于Android平台与MVC模式的歌手竞赛系统的方法。该系统是客户端/服务器结构的,使用Servlet和JSP技术,并采用了改进的MVC设计模式,将Spring MVC与MyBatis技术结合起来。服务端利用Tomcat搭建Web容器,用开发工具Eclipse对服务器编程,并用MySQL数据库提供数据层应用。该系统在移动终端上进行了测试,可以实现线上报名,上传作品,互动分享,查看排名,以及对选手进行评论,投票等功能。该系统的实现可以使线上歌手竞赛随时随地的进行,从而使参赛过程更加便利和高效。     

二维超高效液相色谱-四极杆/飞行时间质谱法解析替考拉宁杂质

建立了二维超高效液相色谱-四极杆/飞行时间质谱法（2D-UPLC-Q/TOF-MS）对替考拉宁组分分离和杂质结构解析的分析方法,有效地解决了流动相中含不挥发性磷酸盐的色谱系统不适用于液相色谱-质谱快速鉴定替考拉宁杂质的难题。一维超高效液相色谱以Octadecyl silica （ODS） hypersil色谱柱（250 mm×4.6 mm, 5 μm）进行色谱分离,以3.0 g/L磷酸二氢钠溶液（pH 6.0）/乙腈=9/1 （v/v）为流动相A、3.0 g/L磷酸二氢钠溶液（pH 6.0）/乙腈=3/7 （v/v）为流动相B进行梯度洗脱;二维超高效液相色谱以Waters ACQUITY UPLC BEH C₁₈色谱柱（50 mm×2.1 mm, 1.7 μm）进行脱盐,以0.01 mol/L甲酸铵（pH 6.0）和乙腈为流动相进行梯度脱盐洗脱。质谱在电喷雾离子源、正离子模式下,采用全信息串联质谱（MS^E）模式采集质谱数据,锥孔气流速50 L/h,锥孔电压60 V,离子源温度120 ℃,雾化气流速900 L/h,雾化气温度500 ℃,毛细管电压2500 V,碰撞能量20~50 eV。根据杂质精确质量数及其二级质谱信息推导其结构,并对替考拉宁主要成分TA_2-2的裂解规律进行了推导,发现了2个母核特征离子;对《欧洲药典》10.0收录的10个组分及22个杂质组分进行二级质谱分析,发现了3个新杂质组分。采用该法既可以使用一维超高效液相色谱根据相对保留时间进行组分准确定位,也可以使用二维超高效液相色谱-四极杆/飞行时间质谱二级质谱信息快速、简便、灵敏地对杂质进行结构鉴定,为替考拉宁的质量控制和工艺优化提供了一种新思路。     

Controlled drug release from bifunctionalized mesoporous silica

Serial of trimethylsilyl-carboxyl bifunctionalized SBA-15 (TMS/COOH/SBA-15) have been studied as carriers for controlled release of drug famotidine (Famo). To load Famo with large capacity, SBA-15 with high content of carboxyl groups was successfully synthesized by one-pot synthesis under the assistance of KCl. The mesostructure of carboxyl functionalized SBA-15 (COOH/SBA-15) could still be kept even though the content of carboxyl groups was up to 57.2%. Increasing carboxyl content could effectively enhance the loading capacity of Famo. Compared with pure SBA-15, into which Famo could be hardly adsorbed, the largest drug loading capacity of COOH/SBA-15 could achieve 396.9 mg/g. The release of Famo from mesoporous silica was studied in simulated intestine fluid (SIF, pH=7.4). For COOH/SBA-15, the release rate of Famo decreased with narrowing pore size. After grafting TMS groups on the surface of COOH/SBA-15 with hexamethyldisilazane, the release of Famo was greatly delayed with the increasing content of TMS groups.     

Modular pathway engineering of diterpenoid synthases and the mevalonic acid pathway for miltiradiene production

Microbial production can be advantageous over the extraction of phytoterpenoids from natural plant sources, but it remains challenging to rationally and rapidly access efficient pathway variants. Previous engineering attempts mainly focused on the mevalonic acid (MVA) or methyl-d-erythritol phosphate (MEP) pathways responsible for the generation of precursors for terpenoids biosynthesis, and potential interactions between diterpenoids synthases were unexplored. Miltiradiene, the product of the stepwise conversion of (E,E,E)-geranylgeranyl diphosphate (GGPP) catalyzed by diterpene synthases SmCPS and SmKSL, has recently been identified as the precursor to tanshionones, a group of abietane-type norditerpenoids rich in the Chinese medicinal herb Salvia miltiorrhiza . Here, we present the modular pathway engineering (MOPE) strategy and its application for rapid assembling synthetic miltiradiene pathways in the yeast Saccharomyces cerevisiae . We predicted and analyzed the molecular interactions between SmCPS and SmKSL, and engineered their active sites into close proximity for enhanced metabolic flux channeling to miltiradiene biosynthesis by constructing protein fusions. We show that the fusion of SmCPS and SmKSL, as well as the fusion of BTS1 (GGPP synthase) and ERG20 (farnesyl diphosphate synthase), led to significantly improved miltiradiene production and reduced byproduct accumulation. The MOPE strategy facilitated a comprehensive evaluation of pathway variants involving multiple genes, and, as a result, our best pathway with the diploid strain YJ2X reached miltiradiene titer of 365 mg/L in a 15-L bioreactor culture. These results suggest that terpenoids synthases and the precursor supplying enzymes should be engineered systematically to enable an efficient microbial production of phytoterpenoids.     

苹果酸酶结合域定点突变对烟酰胺腺嘌呤二核苷酸类似物催化性能的影响

通过对苹果酸酶(ME)辅酶结合域L310、Q401、L404饱和位点突变库与辅酶烟酰胺腺嘌呤二核苷酸(NAD⁺)类似物库的高通量筛选,研究了苹果酸酶结合域位点对NAD⁺及其类似物(B1~B7)催化活性的影响。 结果表明,突变后酶ME-Q401H/L404T对类似物B4的k_cat/K_m是野生型酶的50倍;突变后酶ME-L310M/Q401N对类似物B4的k_cat/K_m是野生型酶的16倍,对类似物B3的k_cat/K_m是野生型酶的5倍,因此通过对结合域定点突变,NAD⁺类似物的催化活性得到提高。     

PVDF梳状换能器接收非线性兰姆波的实验研究*

该文基于PVDF压电薄膜对梳状换能器进行设计制作,并将该换能器应用于接收非线性兰姆波信号实验研究。首先通过输出矢量和方法分析PVDF梳状换能器的工作特性,然后将设计制作的PVDF梳状换能器应用于铝板中非线性兰姆波信号的接收,并与传统压电陶瓷换能器经斜劈接收的非线性兰姆波信号进行比较分析。实验结果表明,两种换能器所接收到的信号幅值随传播距离的变化趋势相近,线性增长的积累效应表征结果相似,且PVDF梳状换能器可以对基波和二次谐波信号同时响应。除此之外,PVDF梳状换能器用于接收非线性兰姆波信号更加稳定。因此,PVDF梳状换能器有望应用于复杂构件的在线检测与监测研究。     

可折叠航天结构展开动力学分析

以欧拉参数为广义坐标（准坐标）,相对角速度和相对移动速度为广义速率,采用Ｋａｎｅ方程的Ｈｕｓｔｏｎ形式建立多体系统的运动力学方程。由伪上三角分解求约束Ｊａｃｏｂｉ矩阵的正交补阵,约简约束力,从而将运动方程由微分几何方程（ＤＡＥ）变为常微分方程（ＯＤＥ）,并由Ｇｅａｒ法对ＯＤＥ积分求出运动历程。最后给出一伸展臂数值分析算例。