利用传感器探究光质对光合作用的影响

改进人教版教材原有探究实验“探究环境因素对光合作用强度的影响”的实验装置,利用传感器和光谱仪精确地测定了光波长和光合速率之间的线性关系,将定性分析与定量研究相结合,有效培养了学生的科学思维和科学探究能力。实验结果表明,绿萝叶片的光合速率随光波长的增加先减小后增大又减小,蓝光（446 nm）和红光（640 nm）处光合速率最大,绿光（516 nm）处光合速率最小。     

入射光波长对硅太阳能电池特性的影响

为了提高硅太阳能电池的效率,研究了入射光波长对硅太阳能电池表征参数的影响。实验中采用恒定功率的白炽灯为光源,经过不同的滤光片后得到不同波长的光,测定了在不同波长的入射光照射下硅太阳能电池表征参数的变化。结果表明,随入射光波长的增大,硅太阳能电池的开路电压、短路电流、最大输出功率和填充因子都逐渐增大。实验过程中还发现,在入射光波长436 nm时,硅太阳能电池表面的氮化硅增透膜对硅太阳能电池表征参数产生的影响较大。     

家庭实验五则

实验以其形象、直观的特点，在化学教学中起着举足轻重的作用。而学生若能利用身边的废旧物品，自己动手在家里做实验，既可以激发学生的学习兴趣从而巩固课本知识，又能培养学生勤于钻研的科学态度，若能坚持，无疑是实施素质教育的好办法。本人经多次实验、改进，总结了几条与高中课本知识相关的小实验，有的实验确是知识难点的有力阐释：１漂白旧报纸实验目的：验证ＳＯ２的漂白作用及漂白的不稳定性用品：发黄旧报纸一块，塑料饮料瓶（雪碧、可口可乐小瓶或纯净水瓶均可）一个，火柴。实验步骤：（１）将塑料瓶自瓶口向下约２０ｃｍ处用…     

基于体全息技术的WDM器件衍射效率均匀性研究

对基于体全息技术的WDM器件的衍射效率均匀性进行研究.为获得尽可能均匀的衍射效率,除了考虑传统的光擦除效应外,更进一步考虑到耦合光路几何组态、各信道衍射光波长、衍射角等因素的影响,利用递推法,推导出更加精确的曝光时序.模拟结果表明,利用该曝光时序,各信道可获得均匀的衍射效率.     

智能手机光谱仪的开发及应用

通过Onshape软件建模并用3D打印机制作了手机光谱仪,并利用ImageJ的Macros语言设计了 自动分析光谱图的脚本.使用手机光谱仪对多种金属盐混合溶液的焰色反应进行拍摄获取到相应的光谱图,运用设计的脚本分析之后得到了各金属离子的特征谱线,发现其与理论上金属元素的特征谱线的误差非常小.实验结果表明手机光谱仪准确度较高,可以用于少量金属元素的定性分析.     

测量顺序对实验影响的研究

本文研究了双棱镜干涉测钠光波长、测液体粘滞系数(落球法)实验中物理量测量顺序对实验结果的影响,得出选择合理的测量顺序有利于节约实验时间、利于提高实验精度。指出在实验中对测量顺序的选择应该引起足够的重视。     

Tevatron上顶夸克极化效应的研究

在顶色辅助的人工色模型框架下，在Tevatron上研究了顶夸克一反顶夸克对的产生过程中顶夸克的极化效应，在计算过程中，我们运用了CTEQ3部分子分布函数和螺旋度投影算符的方法．研究结果表明，考虑极化后，在绝大部分参数空间内，截面修正小于15％，考虑到理论上的不确定性，该修正在实验上不可探测．因此，在Tevatron上通过顶夸克一反顶夸克对的产生来寻求顶色辅助的人工色模型的线索是不可能的．     

掺杂氰基苯乙烯的胆甾相液晶凝胶的双色性能

为了弥补单色防伪不足，设计了“双色”防伪材料的实验。通过缩合反应合成具有聚集诱导发光特性的氰基苯乙烯化合物，然后与向列相液晶、凝胶剂、手性剂物理混合制备兼具荧光和结构色的“双色”胆甾相液晶凝胶材料；利用薄层色谱、掺水实验、核磁共振波谱仪、紫外-可见分光光度计、荧光分光光度计等分析材料的化学结构与颜色性能，并制备字符二级加密以及八卦中的“坎”与“离”图像加密模型。结果表明，制备的双色胆甾相液晶凝胶可用于信息存储与防伪领域。     

两类图色唯一的充要条件

利用图的伴随多项式的性质，给出了两类图色唯一的充分必要条件。     

迈克尔逊干涉仪实验相对误差的探索

基于非定域干涉光程差级数展开的方法,通过对迈克尔逊干涉仪测He-Ne激光波长实验,探索了在干涉图样半径R≠0和不满足非定域干涉两种情况下,激光光波长的理论计算结果和近似结果之间相对误差随参数变化关系。以二阶展开为例,计算了d不同值时相对误差η随R变化关系,实验数据与理论吻合较好。     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

Western and Eastern culture differences in commercial field

The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.     

Improvement of one-cycle controller by use of proportional integral differential controller

1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…     

风的曲线

Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.