“注意”规律在生物演示实验中的应用

演示实验是解决课堂教学中重点或难点的非常有效的直观手段之一,是教师为配合讲授新教材而设计的。它能帮助学生深刻理解生物学的基本概念、原理和规律,同时培养学生观察、分析和解决问题的能力。此外,教师的实验操作是学生进行分组实验的行为规范。故教师应充分利用心理学原理,指导学生对演示实验进行详细的观察、记录和分析。(一)激发学生的无意注意心理学表明,无意注意是一种无预定目的、也不需要经过意志来实现的注意。

如何有效开展化学实验教学——基于“中和反应”实验教学技能比赛评审的思考

基于＂中和反应＂实验教学技能比赛的评审,对参赛选手暴露的相关问题及剖析,阐述加强规范化学实验操作、加强对化学实验教学功能的认识、加强对教材栏目设计意图的理解、加强对实验教学演译的研究四个方面,谈如何有效开展化学实验教学。

氢氯混合气光化反应实验探讨

现行高中化学教材必修本一册四页氯气和氢气光化的演示实验,难度较大,不容易成功。为了保证演示的成功,不但要掌握实验成功的关键,还要明确实验失败的原因。而实验的成败跟反应的原理密切相关。 氯气和氢气光化的链式反应的历程,简述如下: 1、链的引发:该链反应是由作为链中心的氮原子的形成而发生的。

地下电缆的探地雷达图像特征与识别技术

为实现对地下电力电缆的快速探测与识别,提出了基于探地雷达对地下电缆成像的探测与识别方法。首先通过正演实测实验分析了地下带电电缆与非带电介质的探地雷达探测图像波形特征,突出了带电电缆反射波形的特殊性;然后建立了基于磁场叠加原理的常见布线方式下的电缆磁场辐射计算模型,从电缆结构与磁场分布角度解释了电缆探测波形的形成原因及特殊性,进一步突出了电缆与其他非带电地层介质的区别,提出了基于探地雷达对地下电缆成像的探测与识别方法;最后通过反演实验对所提方法进行了验证,实验结果表明所提方法在电缆的探测与识别上具有良好的应用效果。

探地雷达技术在变电站地层隐蔽管线探测中的应用

针对变电站改造和新建过程中由于勘测不足和资料缺失而导致地下隐蔽管线被挖断的问题,提出将探地雷达技术应用于变电站的地层隐蔽管线定位与识别中。首先,通过正演实验分析了常见不同地层介质的灰度图特征;然后,根据单道波形图对典型金属、非金属介质以及电缆的探测波形特征及形成原因进行了系统性分析与总结;最后,通过在宜昌市某110kV变电站中进行的反演实验对探地雷达技术在变电站地层隐蔽管线探测中的应用进行了验证。实验结果表明:使用探地雷达技术能够很好地对地层隐蔽管线进行定位和识别,该技术在变电站改造和新建过程中具有良好的应用优势与应用前景。

新课程的实施与构想

新课程的核心是教会学生如何学习,培养学生学习的兴趣,帮助学生掌握适合自己的学习方法,全面培养提高学生的学习能力,把学习过程由过去的硬性灌输和被动接受,变为启发诱导和主动探索。因此全面贯彻实施新课程理念,对于全面提高教育教学质量、培养创新型人才,是十分必要的,也是我们必须要做好的。鉴于河南省西华县第一高级中学当前的情况,我们准备采取以下措施,强力推进新课程理念的贯彻实施:

海上油田中深层滩坝相沉积规律精细刻画及储层预测技术

滩坝砂岩油藏是一种重要的岩性油藏类型,具有分布复杂、预测难度大的特点。以渤海南部海域A油田为研究对象,探索出一套适用于海上大井距条件下中深层滩坝相储层沉积规律精细刻画和预测技术。首先通过大量的岩心观察,明确研究区滩坝相沉积背景;其次通过精细古地貌恢复明确大规模滩坝砂分布的可能,综合古水动力和古风力研究明确沉积边界;最后通过地球物理正演实验和Geo Frame软件的LPM模块技术,确定出滩坝砂体的沉积厚度。研究结果表明该技术具有较好的应用性,为海上油田中深层滩坝相储层精细刻画提供了新思路。

Experiments on Channel Evolution Caused by Check-dam Failure

A 10 m long,0.2 m wide flume was employed to simulate the channel bed evolution of check-dam failure.The experiment longitudinal profiles,the gradient of channel bed,head-cutting propagation distance and deposition length were compared with the theoretical solution derived from a sediment transport diffusion equation.In contrast with the theoretical solution,two different gradients were obtained upstream and downstream of the check-dam.The theoretical solution provides a good description of the changes upstream of the check-dam. The ratio of clear water depth to sediment moving layer thickness in the experiment was analyzed and showed that high concentration sediment laden flow was taken in the incipient of check-dam failure,which may be the reason why the experiment result was slightly different from the theoretical solution in the downstream of check-dam.

Design optimization of a slotless PM brushless motor with helical edge wound laminations for rim driven thrusters

This paper discusses the analysis and design of a very thin slotless permanent magnet （PM） brushless motor whose stator laminations are manufactured from a single strip of steel that is edge wound into a spiral （like a ＂Slinky＂） and then fitted over the windings that are preformed on the outside surface of a non-conducting former. Analytical and finite element analysis （FEA） are used to determine the con- strained optimum dimensions of a motor used to drive a rim driven thruster in which the motor rotor is fit- ted onto the rim of the propeller and the stator is encapsulated in the thin Kort nozzle of the thruster. The paper describes the fabrication of a demonstrator motor and presents experimental results to validate the theoretical calculations. Experimental motor performance results are also reported and compared with those of a slotted motor that fits within the same active radial dimensions as the slotless motor. The slotless motor, which has longer active length and endwindings, and thicker magnets than the slotted motor, was found to be less efficient and more expensive （prototype cost） than the slotted machine.

Experiments on Channel Evolution due to Dam Removal in Taiwan

Due to safety concerns and habitat restoration for landlocked salmon,a 13-m high check dam on Chijiawan Creek was removed in late May 2011 in Taiwan.We conducted experiments to understand channel evolution of different scenarios.We further compared our experimental results of riverbed elevation changes with the analytical solutions derived from the diffusion equation and field dynamics as well after the creek experienced the first flood event.The results indicated that magnitude of discharges and notch size are dominant factors in resulting channel evolution.While the largest differences between grain size distribution are associated with discharge,the largest differences in net change in upstream volume are associated with notch size.While the theoretical equation could help understand the channel change after dam removal,it only explained the evolution closer to the dam.The physical experiments,on the other hand,provided insights especially with regard to comparing alternative proposed management actions.The discrepancies between predicted and actual outcome highlight more needed inputs for future dam-removal assessments.

The Free-Flowing Voice and its Connection With the Mother Tongue

Does the native tongue confer greater authenticity and connection？ And how does this connect with languages acquired later in life？ From thirty years of directing, training, and auditioning actors from a range of ethnicities, I have believed that the mother-tongue has a particular and organic connection for an actor, one difficult to achieve in any other language. This belief was confounded in a laboratory conducted with Romanian actors, March 2013. The work was performed in both English and Romanian and it was with a sense of shock that I observed that the work was more vital, compelling, and physically and vocally engaged when they spoke in English. What were the factors at play here and what are the implications for future work？ Patsy Rodenburghas written of the giddy delight children find in language. Under what conditions does the native tongue evoke that ＂giddy delight＂ and where and when does it become an obstacle to such pleasure？

A method for retrieving soil moisture from GNSS-R by using experiment data

Soil moisture is a key parameter in agricultural irrigation. The L band（1.58GHz） on board global position system （GPS） satellite is well suited for monitoring the change of soil moisture. In order to investigate the potential of retrieving soil moisture using the L-band GPS bistatic radar, this paper analyzed a retrieval method by using field experiment data. In order to investigate the relation- ship between the soil moisture （ corresponding roughly to the 0 - 5cm top soil layer） and the signal- to-noise ratio （PT-S-R） to the direct GPS signal-to-noise ratio （Pd_sNR）, an experiment was conducted in Hulunber grassland of China in 2009 and 2011. Six field sites in the soil moisture experiment were utilized to analyze the relationship between soil moisture and the ratio of Pr-SNR to Pd-SN~ and the square of correlation coefficient was about 0.9 when the surface type was known and the elevation angle of the satellite ranged from 65 to 85 degrees approximately. The analysis shows that ratio of Pr-SNR to Pd-SNR can be used to monitor the soil moisture, because the ratio of Pr-SVR to Pd-SNR maxi- mized the elimination of the influence of different signals from different GPS satellites. The estimation accuracy could be improved if we make full use of the empirical knowledge on elevation angles of GPS satellites and ground roughness of different surface types.

Experimental Evidence of the Formula of Saturation

There is more than one definition of the saturation ofcolour. In 2008, the author proposed a new formula for the saturation and in this presentation the experimental verification is shown by means of the Japanese Colour System PCCS, The distances in the lines of equal saturation have three maxima and three minima. A connection to neurology and to the colour sensation is possible. Making a new colour space with the saturation, the LSh-colour space, which is much more symmetrically than the LCh-colour space. This is of interest for calculating colour differences.

Analysis on the Enlightenment from Comprehensive Musicianship Course on the Teaching of Vocal Music Performance

Excavation to creativity is one of important means in the teaching process. Comprehensive musicianship course is an experimental teaching method, but also a teaching art form in the music education system. Many achievements have been made to comprehensive musicianship course since the experimental teaching was established in China. The influence scope of comprehensive musicianship course is constantly expanded in the field of social music teaching, and simultaneously its influencing power is also rising. However, it should be implemented in the process of teaching according to the actual circumstances of the primary and secondary school students in China. In the teaching of comprehensive musicianship course, vocal music performance is applied as the main carrier in form and proceeds very rhythmically in the process of the whole time, and also thoughts and emotions are fully reflected by body languages. It starts from the comprehensive learning, and then is gradually promoted between non-major courses in institutions of higher learning and the music teaching in primary/secondary schools, so that a good teaching effect has been obtained. In comprehensive musicianship course, high importance is attached to the improvement of students＇ creativity and innovation ability. In this paper, the enlightenment from comprehensive musicianship course on China＇ s vocal music performance teaching is mainly analyzed.

Speed Geometric Quantum Logical Gate Based on Double-Hamiltonian Evolution under Large-Detuning Cavity QED Model

We introduce the double-Hamiltonian evolution technique approach to investigate the unconventional geometric quantum logical gate with dissipation under the model of many identical three-level atoms in a cavity~ driven by a classical fieM. Our concrete calculation is made for the case of two atoms for the large-detuning interaction of the atoms with the cavity mode. The main advantage of our scheme is of eliminating the photon flutuation in the cavity mode during the gating. The corresponding analytical results will be helpful for experimental realization of speed geometric quantum logical gate in real cavities.

A Practical Hull Form Design of Ferry Using Hybrid Scheme Method and Performing Experiment

Prediction of ship performance in preliminary ship design is an important consideration. It could guarantee ship in safe and comfort. However, many design works did not involve simultaneously ship performances predictions in preliminary design. Moreover, ship designers sometimes modified a ship form to obtain proper design without ship performance consideration. Therefore, this study concerns on predictions of total resistance and added wave resistance of a ferry using a hybrid particle-grid method and then its motions response after modifying bow and stern parts by conducting experiment. Research results show total resistance and added wave resistance have a significant different, therefore, it would be an important consideration in determining ship powering in preliminary ship design. The non-dimensional added wave resistance increases in increasing wave length from λ/Lpp = 0.5 to 1.0 and it decreases after L/λ = 1.0. In addition, it tends to decrease caused by increasing ship speed. The comparison of averaged heave and pitch amplitudes between basic forms after modifying bow and stem parts is quiet similar. However, the rolling amplitude of the modified form is significantly higher comparing with the basic form. We conclude that a ship could be design in preliminary design take into account performances predictions by using numerical method and experimental work.

中学化学课堂教学中有效提问的实践与思考

古人云:"善问者如敲钟,叩之小者则小鸣,叩之大者则大鸣。"对教学而言,说的是教师要"善问"、"巧问",以引起学生的共鸣。早在公元前5世纪,古希腊卓越的哲学家苏格拉底就以提问为基础展开教学(被称为"产婆术")。提问在课堂教学中历史悠久、使用广泛,是激发学生学习兴趣、促进师生相互作用、实现教学反馈的重要途径。教师通过提出问题来检查和了解学生对知识的理解程度和技能的掌握程度。

Influences of water media on the hydrogen isotopic composition of natural gas/methane in the processes of gaseous hydrocarbon generation and evolution

The influences of water media on the hydrogen isotopic composition of organic-thermogenic natural gas were tested in three series of experiments on coal pyrolysis, with no water, deionized water （δDH2O-58‰）, and seawater （δSDn2O=-4.8‰） added, respectively. The experimental results show that the productivities of H2 and CO2 obviously increased under hydrous conditions and that the productivity of CH4 also remarkably increased in the high-evolution phase of hydrous experiments. Water was involved in the chemical reaction of hydrocarbon generation, and then the hydrogen isotopic composition of methane was affected. There is a linear correlation between the hydrogen isotopic composition of methane and its productivity, as reflected in the three series of experiments. In the case of the same CH4 productivity, the hydrogen isotopic composition of the methane produced in anhydrous experiments was the heaviest, that of the methane produced in seawater-adding experiments came second, and that of the methane produced in deionized water-adding experiments was the ligbtest. The hydrogen isotopic composition of natural gas/methane is affected by the following factors： 1） the characteristics of hydrogen isotopic composition of organic matter in source rocks, 2） the thermal evolution extent of organic matter, and 3） fossil-water media in the natural gas-generation period. The experimental results show that the influence of the fossil-water medium in the natural gas-generation period was lower than that of the other factors.

Theory, experiment and applications of metamaterials

In this review article, a brief introduction on the theory, experiments and applications of metamaterials is presented. The main focuses are concentrated on the composing meta-atoms, the method of transformation optics, the experimental demonstration of negative refraction, and the realizations of invisibility cloaks and electromagnetic black hole. At the end of this review, some typical applications of metamaterials, including high-performance antennas made of zero-refractive-index materials, inhomogeneous metamaterial lenses, and planar metasurfaces, are introduced in details.