混合纤芯光子晶体光纤超平坦色散的研究

利用平面波展开法,系统地研究了一种具有混合纤芯结构的光子晶体光纤的色散特性. 数值计算结果表明,通过优化结构参量,这种新型结构的光子晶体光纤在通信窗口1.55 μm 附近可以获得带宽超过800 nm的超平坦色散区域（色散曲线的变化范围不超过 ±0.6 ps·km－1·nm－1）.     

不同环境条件下水稻叶片中叶绿体内碳酸酐酶活性的变化

以水稻(Oryza．Sativa L．)为材料,在不同光照、高盐、高温及缺N、K培养等条件下研究碳酸酐酶活性的变化。结果表明;在16μmolES^-2-64μmolES^-2。光强范围内,随着光照的增加,碳酸酐酶活性并无明显的变化．在高盐逆境条件下碳酸酐酶活性降低2-3倍,在高温逆境条件下碳酸酐酶活性降低了2～4倍,在缺N培养条件下碳酸酐酶活性降低了7-8倍,在缺K的培养条件下碳酸酐酶活性降低了2—3倍。     

“生物学综合实验”国家级精品课程建设的探索与实践

课程建设是教学建设的基本内容,是人才培养质量的根本保证。回顾湖北师范学院生物学综合实验国家级精品课程建设历史的沿革,着重对该课程的建设思路、措施与成效进行了较为全面的总结。     

在生物化学实验教学中发挥学生主体性的教学策略

学生主体性教学是以促进学生主体性发展为目的,充分发挥学生学习主动性和创造性的一种教学方式。在多年的生物化学实验教学实践过程中,通过组织学生参与预备实验,以问题为基础进行教学,引导学生自主设计实验,提倡交流和讨论等教学策略,促进了学生主体性的发展,提升了实验教学效果。     

Subpicosecond pulse compression in nonlinear photonic crystal waveguides based on the formation of high-order optical solitons

We investigate by numerical simulation the compression of subpicosecond pulses in two-dimensional nonlinear photonic crystal (PC) waveguides. The compression originates from the generation of high-order optical solitons through the interplay of the huge group-velocity dispersion and the enhanced self-phase modulation in nonlinear PC waveguides.Both the formation of Bragg grating solitons and gap solitons can lead to efficient pulse compression. The compression factors under different excitation power densities and the optimum length for subpicosecond pulse compression have been determined. As a compressor, the total length of the nonlinear PC waveguide is only ten micrometres and therefore can be easily incorporated into PC integrated circuits.     

Investigation and Modification of Coupling of Photonic Crystal Defects

We investigate the coupling of photonic crystal (PC) defects by using coupled-mode theory. The PC molecules formed by the coupling of two identical PC atoms are the focus of our study. It is revealed that the flatness of the transmission spectra of the PC molecules is determined uniquely by the phase shift of the travelling wave between the two coupled PC atoms. By properly adjusting the distance between the two constitutional PC atoms, we are able to modify the transmission spectrum of the resulting PC molecule. Theoretical analyses based on the coupled-mode theory are in good agreement with the simulation results obtained by the transfer matrix method and the finite-difference time-domain technique.     

微课在生物化学实验教学中的应用

微课是当今信息化时代一种新型的学习资源和教学手段。将微课应用于生物化学实验教学中,可以突破课时、教室对传统实验教学的限制,创建自主性、开放性实验课堂,发挥学生的主体性,促进师生的交互发展,体现教师的教学智慧,适应教育信息化。微课在实验教学中的应用模式,是生物学实验信息化建设和教学改革的创新实践。     

Formation of Optical Solitons in Nonlinear Photonic Crystal Waveguides

Relying on the huge group velocity dispersion available in photonic crystal (PC) waveguides, we observe the formation of both Bragg grating solitons and gap solitons in nonlinear PC waveguides in numericalexperiments. Also, we indicate the potential applications of optical solitons in optical limiting, optical delay, and pulse compression and the feasibility of observing optical solitons in practical experiments.     

钙对食用蓝藻葛仙米生长、形态建成和光合作用的影响

探讨钙对葛仙米生长、形态建成和光合作用的影响。结果表明:在0、0.24和10 mmol·L-1三种钙浓度条件下培养14 d,葛仙米比生长速率μ值无显著差异,但是葛仙米球体百分数分别增加到40%,50%和85%.随着钙浓度的提高,光饱和点Ik、光补偿点Ic、暗呼吸速率Rd、光合效率α均变化幅度不大,但是其Pmax显著增加了16%.相对于无外源钙条件下,较高钙浓度水平(10 mmol·L-1)条件下培养的葛仙米的Vmax和K0.5(DIC)也分别显著性增加了51%和28%.该结果说明高钙浓度可以促进葛仙米的形态建成和提高其光合能力。     

新课程标准下的个性化阅读教学

正确理解个性化阅读，创设自学情境，鼓励学生质疑。重视讨论交流，能使语文课堂生动活泼，能让作为学习主体的学生养成良好的阅读习惯，形成适合自身发展的阅读理解能力和鉴赏水平。