火焰原子吸收法对高含量氯化锌的快速测定

介绍了火焰原子吸收采用次灵敏线测定高含量氯化锌的方法,并确定了仪器的最佳工作条件。该方法快速、简便、准确,利用本方法测定高含量氯化锌得到了满意的结果,样品测定的回收率为97．5％－102．5％,相对标准偏差为0．49％－1．01％。     

端视ICP-AES法测定水中的有机碳

本文建立了利用端视ＩＣＰ－ＡＥＳ技术测定水中有机碳的方法。本法检出限为０．６ｍｇ／Ｌ,灵敏度比国外同类方法提高了大约八倍,方法精密度好,其相对标准偏差０．４％￣３．２％（ｎ＝６）,回收率在８３．６％￣１０９．０％之间,本法前处理简单,测定速度快,灵敏度高,适合天然水中有机碳的测定。     

微波消化-氢化物原子荧光法测定水产品中的铅

采用微波消化技术溶解水产品,以氢化物－原子荧光法测定铅,讨论并确定了最佳测定条件,结果表明,铅的测定线性范围为0－100ng/mL,方法的相对标准偏差为1．2％－5．3％,回收率为94．8％－103．5％。该方法简便、快速,用于水产品中铅的测定,获得令人满意的结果。     

ICP-AES法直接测定阳极泥中的金和银

使用ICP－AES法同时测定了多个阳极泥样品中的金和银。加标回收率为95．4％－103．2％,10次测定的RSD为0．8％－4．8％。方法简便,速度快,结果准确。     

原子吸收火焰分光光度法测定锌精矿中的氧镁

本文研究了原子吸收火焰分光光度法测定锌精矿中的氧化镁含量的方法。方法简便、快速,结果满意。测定范围：０．２％－５．０％。     

盐酸环丙沙星含量测定方法的研究

本文介绍了盐酸环丙沙星含量测定的离子选择电极法，紫外分光光度法和格兰线性滴定三种不同方法。用于原料药回收率的测定分别为９９．４％，９９．６７％和９９．５％；用于片剂回收率测定分别为９８．８５％，９８．８４％和９８．７３％。结果基本相同，与非水滴定法相比具有测试方便、快速等优点。     

火焰原子吸收法测定高铝锌基合金中的铜

提出了用火焰原子吸收光谱法测定高铝锌基合金中铜含量的方法,在本法测定条件下,基体元素及其他共存元素不干扰,可测定质量分数为２．０％－３．０％范围内的高铝锌基合金中的铜。该方法相对标准偏差为０．８６７％,样品加标回收率为９８．４％。     

紫外分光光度法测定脑维营养麦片中的卵磷脂

本文报道了用紫外分光光度法测定及维营养麦片中添加的卵磷脂含量,该方法无需消解,显色,并且简便,快速,测定结果令人满意,回收率为98．2％－101．3％,RSD为1．2％。     

光电直读光谱仪同时测定金属铝中15个元素

本文研究了用光电直读光谱法同时测定金属铝中１５个元素的方法,对光源及测定条件进行了最佳选择,具有测定时间短,灵敏度、准确度高等优点。含量在０．１－１％之间,ＲＳＤ〈３％含量在０．００１－０．１％之间,ＲＳＤ〈６％;含量〈０．００１％,ＲＳＤ〈１４％,经与化学法比对,结果十分吻合。     

生殖液中锌元素含量的测定方法研究--环境与生殖健康课题

在体液中金属元素的测定方面,国内外对血液、血浆、唾液等研究得比较多,对生殖液的研究则相对较少,到目前为止,尚未发现有关这方面的文献。在没有现成资料的情况下,测定了对生殖起关键影响元素之一的锌元素。对样品的处理、用量、测定参数的选择等方面进行了研究,建立了一套测定精液和卵泡液中锌的简洁可靠的方法,该方法对锌的加标回收率在92．0％～107．6％之间,最低检出浓度为0．002mg．L^-1,相对标准偏差在1．3％～10．0％之间。     

Self-organization of five species in a cyclic competition game

Cyclic competition game models, particularly the “rock–paper–scissors” model, play important roles in exploring the problem of multi-species coexistence in spatially ecological systems. We propose an extended “rock–paper–scissors” game to model cyclic interactions among five species, and find that two of the five can coexistent when biodiversity disappears, which is different from the “rock–paper–scissors” game. As the number of fingers is five, we named the new model the “fingers” game, where the thumb, forefinger, middle finger, ring finger, and little finger cyclically dominate their subsequent species and are dominated by their former species. We investigate the “fingers” model in two ways: direct simulations and nonlinear partial differential equations. An important finding is that the number of species in a cyclic competition game has an influence on the emergence of biodiversity. To be specific, the “rock–paper–scissors” model is in favor of maintaining biodiversity in comparison with the “fingers” model when the variables (population size, reproduction rate, selection rate, and migration rate) are the same. It is also shown that the mobility and reproduction rate can promote or jeopardize biodiversity.     

Experimental study on downstep in Chinese intonation

Downstep in pitch contour of Chinese Putonghua is examined using subtly designed sentences by controlling tone combinations. The results show both automatic and nonautomatic downstep phenomena exist in Chinese. In non-automatic downstep, low tones compress downwards the pitch range of the following syllables. and the main influence of downstep is on topline. Low tone not only lower the topline behind it, but also raise the high tones before it, the effects are compatible with each other. In automatic downstep, the topline of pitch contour in intonational phrase is presented as a linear downtrend, but it differs among speakers due to the effect of personal stress practice. In comparison with downstep phenomenon in other tone or non-tone languages, the downstep ratio in Chinese is not constant, and the domain of downstep is not limited within the adjacent tones.     

Contrastive analysis on tone between Putonghua and Taiwan Mandarin

The differences of the pitch and duration of Chinese syllables between Putonghua （PTH） and Taiwan Mandarin （TM） were studied. The speech materials to be used are not only isolated syllables, but also sentences. The results reveal that： For the isolated syllables, T1 and T2 in TM are influenced by Minnan dialect, therefore their pitch are lower than those in PTH. T3 is fall-rise in PTH, while it is fall in TM. Moreover, the syllable duration sequence for different tone is T3〉T2〉T1〉T4 in PTH, while it is T1〉T2〉T3〉T4 in TM. For the syllables in sentences, T2 is mid-rise in PTH, while it is mid-level in TM. And the T3 is longer than T4 but shorter than T1 or T2 in PTH, while it is the shortest in TM. Furthermore the effects of prosodic phrase boundary on duration for different tones are almost the same in PTH, but the lengthening part of T1 or T2 is longer than that of T3 or T4 in TM.     

Abelian-Higgs phase of SU(2) QCD and glueball energy

It is shown that SU(2) QCD admits an dual Abelian-Higgs phase, with a Higgs vacuum of a type-Ⅱ superconductor. This is done by using a connection decomposition for the gluon field and the random-direction approximation. Using a bag picture with soft wall, we presented a calculational procedure for the glueball energy based on the recent proof for wall-vortices [Nucl. Phys. B 741(2006)1].     

High efficiency filtering using two-dimensional photonic crystal coupled cavity structures

Transmission spectra of coupled cavity structures (CCSs) in two-dimensional (2D) photonic crystals (PCs) are investigated using a coupled mode theory, and an optical filter based on CCS is proposed. The performance of the filter is investigated using finite-difference time-domain (FDTD) method, and the results show that within a very short coupling distance of about 3λ, where λ is the wavelength of signal in vacuum, the incident signals with different frequencies are separated into different channels with a contrast ratio of 20 dB. The advantages of this kind of filter are small size and easily tunable operation frequencies.     

Signal generation in an isotropic medium in scanning electron acoustic microscope

Based on the research in Ref. [5][Materials Science and Engineering, 1989; A122： 57 63], an improved model of heat source is set up, the different modes of Lamb wave in an isotropic sample generated by a chopped electron beam at frequency f are obtained with integral transform and normal function expansion method, and the output signal of PZT coupled at the back surface of the sample is found out. The generation mechanism of SEAM （Scanning Electron Acoustic Microscopy） signal is discussed. It shows that the SEAM is a near field imaging technique with high spatial resolution and its best lateral spatial resolution is about 2√2α （α is the radius of the focused electron beam）. Some of experimental results of SEAM images are presented in the paper and it shows that the spatial resolution of SEAM is better than 0.5 μm and smaller than the thermal diffusion length of the sample. Therefore the character of near field imaging in SEAM is also proved experimentally.     

Real-time restoration of rotational blurred image using gradient-loading

The key to the restoration of rotational motion blurred image is how to restore the image under a low cost and to correct the irreversibility of the degradation function matrix.Based on the special qualities of degradation function matrix and precise deduction in space-domain, we present a new approach using gradient-loading for restoration of rotational blurred image.By easily adding a gradient operator, the irreversibility of the original matrix is corrected and can be applied for inverse filtering then.Gradientloading is the optimized approach which combines the advantages of both the approaches using constrained least square filtering and traditional diagonal-loading.Compared with the approach using least square filtering, its peak signal-to-noise ratio (PSNR) is improved from 3.18 to 6.46dB, while the computing time is reduced to 1/2-1/3.Experimental results demonstrate the effectiveness, noise-resistibility, robustness, and low complexity of this approach, which make it more suitable for real-time environment.     

All-Optical Logic Device Using Bent Nonlinear Tapered Y-Junction Waveguide Structure

We propose an all-optical logic device made of a bent tapered Y-junction waveguide with a Kerr-type nonlinear interface. It could provide an AND gate, OR gate, and exclusive-OR (XOR) gate. We could obtain different transmission results by adjusting the bending angle. The numerical simulation results show that the device functions as AND, OR, and XOR gates.     

Real-time, continuous-wave terahertz imaging by a pyroelectric camera

Real-time, continuous-wave terahertz (THz) imaging is demonstrated. A 1.89-THz optically-pumped farinfrared laser is used as the illumination source, and a 124 × 124 element room-temperature pyroelectric camera is adopted as the detector. With this setup, THz images through various wrapping materials are shown. The results show that this imaging system has the potential applications in real-time mail and security inspection.