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1.
We report our results pertaining to the use of injectable autologous collagen for the correction of dysphonia resulting from a glottic gap. To date 20 cases have been treated, 13 of which were for unilateral vocal fold immobility and 7 for sulcus vergeture and/or scar. Collagen is extracted from the skin. Approximately 5 cm2 is necessary to yield 2 ml. Injection must take place in the deep layer of Reinke's space. No patient suffered from any local or general intolerance. The phonatory glottic gap was totally or partially closed. In the paralysis group, the improvements were the following: the median maximum phonation time improved from 5.8 seconds to 11 seconds, the median mean flow rate from 0.13 ml/s to 0.09 ml/s, the median glottic gap from 8.4 to 4.5 ml/dB per s, the median intensity range from 21 to 29 dB, and the median frequency range from 141 to 195 Hz. The spectral analysis layout classification improved from 2 to 3.  相似文献   

2.
泥炭,软褐煤中的腐殖质的荧光光谱研究   总被引:2,自引:0,他引:2  
对滇西镇安盆地泥炭,软褐煤中的腐殖质进行了荧光光谱研究,发现它们的荧光性质很复杂,有些腐殖质可以象稳定组分一样发出橙黄至黄色荧光,I546=8.13~13.17单峰或不完全双峰λmax=560~605nm,Q650/500=0.60~2.93;大部分腐殖质不发荧光或发暗棕褐色荧光I546=0~5.38,因荧光太弱而难以获得荧光光谱,但被激发数分钟后,有些不发荧光或发暗棕褐色荧光的腐殖质其荧光会渐泊  相似文献   

3.
ICF靶丸内燃料的气液两相组分组成分析   总被引:1,自引:0,他引:1  
 在质量守恒的基础上,运用拉乌尔定律和道尔顿分压定律,对以摩尔分数比为3∶3∶4比例充入到ICF靶丸内的氘气、氚气和氘化氚三元系的热核燃料,在工作温度为22,24,26,28和30 K下处于相平衡时气液两相的组分组成进行了分析讨论。结果显示:工作温度为22 K时,随着充气压强从1 MPa增大到5 MPa,液层中氘气的摩尔分数从0.251增大到0.290,氚气的摩尔分数从0.350减小到0.310;气泡中氘气的摩尔分数从0.322增大到0.365,氚气的摩尔分数从0.278减小到0.241。充气压强为5 MPa时,随着工作温度从22 K提高到30 K,液层中氘气摩尔分数从0.290减小到0.261,氚气的摩尔分数从0.309增大到0.341;气泡中氘气的摩尔分数从0.365减小到0.302,氚气的摩尔分数从0.241增大到0.298。  相似文献   

4.
采用激光剥蚀电感耦合等离子体质谱(LA-ICP-MS),对枞阳境内出土西周至战国时期青铜器和汤家墩遗址出土炼渣中的铜颗粒进行微量元素原位无损分析,以探讨枞阳县境内出土青铜器的铜矿来源。结果表明,枞阳汤家墩遗址冶炼铜金属颗粒中的Co,As,Sb,Ag和Bi等元素含量较高,其微量元素特征不同于铜陵和铜绿山的冶炼金属铜;从西周至战国时期,枞阳青铜器所用铜矿来源比较稳定,主要来自汤家墩遗址周边的枞阳县境内,有少量器物的铜矿可能来自长江以南的铜陵地区;LA-ICP-MS可用于青铜器和古铜矿冶遗址炼渣中所夹杂铜颗粒的微量元素原位无损分析,从而为利用炼渣探讨古矿冶遗址冶炼金属产品的微量元素特征奠定了基础,对探讨三代青铜器的矿料来源研究具有重要的应用价值。  相似文献   

5.
薛正群  王凌华  苏辉 《发光学报》2018,39(4):534-540
对AlGaInAs多量子阱1 300 nm FP激光器进行反射式倒装封装,在热沉上靠近激光器出光端面约10~20 μm的区域采用Au反射层,对器件垂直方向出光进行反射。测试结果显示,与常规封装相比,采用这种结构封装芯片垂直发散角从34.5°降低至17°,器件单模光纤的平均耦合功率从1 850 μW提高至2 326 μW,耦合效率从21.1%提高到26.5%。对两种激光器进行光电参数的测量,结果表明:与常规封装器件相比,采用反射式倒装结构器件的饱和电流从135 mA提高至155 mA,饱和输出功率从37 mW提高至42 mW,热阻从194 K/W降低至131 K/W。最后对两种器件在95℃环境温度、100 mA电流下进行加速老化实验,老化结果显示:在老化条件下,器件衰退系数从常规封装的4.22×10-5降低至1.06×10-5,寿命从5 283 h提高至21 027 h。  相似文献   

6.
Obsidians from major Ecuadorian sources (outcrops) were analyzed by electron spin resonance, SQUID magnetometry and 57Fe Mössbauer spectroscopy. If the last technique allows to discriminate obsidians from the Quiscatola source, an association of ESR with SQUID magnetometry permits to differentiate obsidians from the sources of Cotopaxi volcano, from the Quiscatola and Mullumica-Callejones sources of the Chacana caldera and to infer that the 12 analyzed obsidians from the pre-Hispanic site of La Maná come from the Mullumica-Callejones source.  相似文献   

7.
激光诱导Co等离子体电子温度的时间空间演化特性研究   总被引:2,自引:1,他引:1  
本文在380~500 nm波长范围内测定了激光烧蚀Co等离子体中Co原子的时间和空间分辨发射光谱.由发射光谱线的强度和Stark展宽分别计算了等离子体电子温度和电子密度,并由实验结果讨论了激光等离子体中电子温度的时间和空间演化特性.实验结果表明,当延时在100~1000 ns范围内变化时,相应的电子温度Te范围为8000~25000 K;当距离靶表面0~1.8 mm范围内变化时,相应的电子温度Te范围为13000~25000 K,电子温度在激光束方向上的分布具有很好的对称性.  相似文献   

8.
用工作波长632.8 nm、功率为2.5 mW的He-Ne激光器辐照铁棍山药,30 min后,其芦头芽萌发受抑,山药茎含水量、可溶性总糖和可溶性蛋白含量分别从70.203 9%下降到66.615 4 4%、从72.213 25 mg·g-1下降到25.878 88 mg·g-1、从508.539 4 μg·g-1下降到258.423 1 μg·g-1,丙二醛(MDA)和超氧阴离子含量分别从0.62 mmol·g-1变为8.033 122 mmol·g-1、从32.997 13 μg·g-1变为35.536 42 μg·g-1,贮藏前期的超氧化物歧化酶(SOD)活性从494.864 U·g-1变为1 105.85 U·g-1,贮藏后期的SOD活性从1 105.85 U·g-1变为959.167 U·g-1.  相似文献   

9.
Nanowires have recently attracted more attention because of their low-dimensional structure, tunable optical and electrical properties for next-generation nanoscale optoelectronic devices. Cd S nanowire array, which is(002)-orientation growth and approximately perpendicular to Cd foil substrate, has been fabricated by the solvothermal method. In the temperature-dependent photoluminescence, from short wavelength to long wavelength, four peaks can be ascribed to the emissions from the bandgap, the transition from the holes being bound to the donors or the electrons being bound to the acceptors, the transition from Cd interstitials to Cd vacancies, and the transition from S vacancies to the valence band,respectively. In the photoluminescence of 10 K, the emission originated from the bandgap appears in the form of multiple peaks. Two stronger peaks and five weaker peaks can be observed. The energy differences of the adjacent peaks are close to 38 me V, which is ascribed to the LO phonon energy of Cd S. For the multiple peaks of bandgap emission, from low energy to high energy, the first, second, and third peaks are contributed to the third-order, second-order, and first-order phonon replica of the free exciton A, respectively;the fourth peak is originated from the free exciton A;the fifth peak is contributed to the first-order phonon replica of the excitons bound to neutral donors;the sixth and seventh peaks are originated from the excitons bound to neutral donors and the light polarization parallel to the c axis of hexagonal Cd S, respectively.  相似文献   

10.
Electron energy loss spectra (ELS) obtained from polycrystalline Pd metal and PdO powder using primary electron energies ranging from 100 to 1150 eV have been obtained and examined in an attempt to gain a better understanding of the origins of the loss features and to assess the utility of ELS in investigations of Pd catalysts. The two sets of ELS spectra differ significantly. The ELS spectra from Pd metal exhibit a predominant peak at 6.5 eV, shown to arise from a surface plasmon excitation, and two broad features at 25.1 and 31.9 eV, which originate from bulk loss processes. The broad features consist of several overlapping losses due mainly to interband transitions from the d-band, though a bulk plasmon excitation is believed to produce a feature near 24 eV. Two distinct peaks are present at 3.7 and 7.6 eV in the ELS spectra obtained from PdO, while a broad region of intensity appears over the range from 20 to 40 eV. The peak at 3.7 eV is attributed to a transition between the top of the valence band and the bottom of the conduction band. The feature at 7.6 eV is broad and arises from several overlapping features that are most likely caused by interband transitions rather than collective excitations. Furthermore, the ELS spectra obtained from PdO and oxidized Pd are also quite different indicating that ELS can provide useful information for determining the bonding states of oxygen on Pd-containing catalysts.  相似文献   

11.
The (15)N study aimed to estimate the portion of nitrogen released from tobacco-waste to be utilized by maize crop. Tobacco-waste at the levels of 0, 2, 4, 6 and 8 g pot(-1) and ((15)NH(4))(2)SO(4) as nitrogen fertilizer labelled with 5 at.% exc. at the levels of 0, 4, 8, 12 and 16 mg N pot(-1) together with a basal dressing of some nutrients were added to pots with Pioneer maize variety. After the harvest, dry matter yield was recorded and (15)N determinations and calculations were made. Tobacco-waste had a positive effect on the growth and on the nitrogen uptake of maize crop. Increasing the rates of tobacco-waste increased the dry matter yield of maize crop from 4.64 g pot(-1) (at control) to 7.22 g pot(-1) (at the tobacco-waste treatment of 8 g pot(-1)). The values of (15)N in the plant derived from nitrogenous fertilizer also increased with increasing nitrogen fertilizer levels, whereas they decreased from 0.427 % to 0.249 % with increasing tobacco-waste treatments from 0 to 8 g pot(-1), respectively. The average values of per cent nitrogen derived from nitrogenous fertilizer (Ndff) varied from 4.32 % to 7.95 % at the rates of 4-16 mg N pot(-1), respec-tively. However, Ndff decreased from 8.54 % to 4.99 % with increasing tobacco-waste treatments from 0 to 8 g pot(-1), respectively. Per cent nitrogen derived from tobacco-waste (Ndft) increased from 21.8 % to 38.5 % with increasing tobacco-waste treatments from 2 to 8 g pot(-1), respectively. The results have revealed that (15)N tracer technique was confidently used for the investigation of nitrogen levels released from tobacco-waste as organic waste to be utilized by maize crop.  相似文献   

12.
The pressure induced phase transitions of TiO2 from anatase to columbite structure and from rutile to columbite structure and the temperature induced phase transition from anatase to rutile structure and from columbite to rutile structure are investigated by ab initio plane-wave pseudopotential density functional theory method(DFT),together with quasi-harmonic Debye model.It is found that the zero-temperature transition pressures from anatase to columbite and from rutile to columbite are 4.55 GPa and 19.92 GPa,respectively.The zero-pressure transition temperatures from anatase to rutile and from columbite to rutile are 950 K and 1500 K,respectively.Our results are consistent with the available experimental data and other theoretical results.Moreover,the dependence of the normalized primitive cell volume V/V0 on pressure and the dependences of thermal expansion coefficient α on temperature and pressure are also obtained successfully.  相似文献   

13.
本文叙述了用火焰原子吸收法直接测定天然螺旋旋藻中的钾、钠、钙、镁、铜、铁、锰、锌等多种元素。方法简单便、快速、准确、可靠,具有良好的精密度和准确度,加收率为96%-103%,相对标准偏差为1.2%-5.2%。应用于国家标准物质甘蓝(GBW08504)的测定,获得了满意的结果。  相似文献   

14.
We study the time of flight optical emission from titanium and tungsten nanosized particles, generated through femtosecond laser-matter interaction in vacuum, in the wavelength spectral range from 300 to 900 nm. Typical spectra consist of broadband structureless signals similar to black body emission from a macroscopic object. Nanoparticles temperature, deduced from their emission spectra, decreases drastically as a function of their time of arrival at a given distance from the target. This behaviour is seen to be independent of individual particle velocities.  相似文献   

15.
Crystal growth occurs following widely different modes; in particular the transition from layer-by-layer to continuous growth, and the transition from stable to dendritic growth have attracted much theoretical attention. The former transition (corresponding, for equilibrium surfaces, to the roughening transition) is considered from the point of view of atom-surface scattering used as a tool to probe the state of the surface, and the effects of roughness on the height, width and shape of the incoherent peaks are studied. As an approach to the latter transition, simulations of cluster growth are considered where dendritic shapes are obtained by letting “atoms” fall along random straight trajectories from a “vapour” onto the growing cluster. Two geometries are considered: either the “atoms” fall along the cords from an outer large circle, or they fall obliquely on to a line from points of a parallel line. In both cases ramified structures are obtained, although less open that from diffusion-limited aggregation (DLA), and their fractal nature is studied.  相似文献   

16.
We report on the application of the single-aliquot regenerative-dose (SAR) protocol to the optically stimulated luminescence signal from quartz extracted from fired bricks and unfired mortar in retrospective dosimetry. The samples came from a radioactive materials storage facility, with ambient dose rates of about 0.1 mGy/h. A detailed dose-depth profile was analysed from one brick, and compared with dose records from area TL dosemeters. Small-aliquot dose-distributions were analysed from the mortar samples; one associated with the exposed brick, and one from a remote site exposed only to background radiation. We conclude that unfired materials have considerable potential in retrospective dosimetry.  相似文献   

17.
郑小平  廖延彪 《光学学报》1998,18(3):57-360
分析了光纤传感器进行双参量测量时,系数矩阵的态性对待测量精度的影响,提出采用对系数矩阵进行预处理的方法,使得处理后的矩阵由病态变成良态。用方法对文献「4」和文献「5」给出的系数矩阵分别进行了处理。处理后,文献「4」系数矩阵的条件数从342降低到4,文献「5」系数矩阵的条件数从161降低到3,传感器输出不确定主降低了两个数量级。  相似文献   

18.
脉冲软X光辐射三种材料的喷射冲量实验研究   总被引:3,自引:1,他引:3       下载免费PDF全文
 在强光一号脉冲加速器上进行了国内首次的实验室软X光辐射三种材料的喷射冲量研究。结果表明,在能量为(0.2~0.33)keV、平均脉宽为39ns左右的X光辐射下,对灰漆、白漆和硬铝,在能注量分别为(92~152)J/cm2、(115~136)J/cm2和(163~192)J/cm2时,它们的冲量耦合系数分别为(0.61~0.80)Pa·s/(J·cm-2)、(0.58~0.97)Pa·s/(J·cm-2)和(0.61~0.84)Pa·s/(J·cm-2)。  相似文献   

19.
绿松石是一种产地有限,却在世界范围内被广泛使用的珍稀宝石资源,研究绿松石文物的矿料来源可为了解古代不同地区间珍稀资源的获取与交流模式、文化传播途径、早期贸易网络等学术问题提供帮助。新疆绿松石文物的矿料来源是近年来科技考古关注的热点问题之一,目前存在中原说、波斯说、新疆说和多元说等观点。研究新疆绿松石文物的产源,其难点在于既要保证文物的安全,又要确保分析数据的准确性,同时要避免样品表面污染对数据结果带来的干扰。鉴于此,采用等离子体原子发射光谱LA-ICP-AES对新疆加依、西沟两处墓地出土的绿松石进行化学成分分析,并结合秦岭东部五处产地的绿松石成分数据,经主成分分析绘制散点图——建立产地区分模型。主成分分析结果显示加依墓地样品中有五枚是罕见的锌绿松石,其余同西沟墓地绿松石的成分相近,均含有相对较高比例的Fe和Sr。结合中原地区的绿松石成分数据对比分析,发现新疆两遗址绿松石的微量元素特征相近,以高B2O低BaO为特征区别于中原地区的绿松石样品。在产地区分模型中,代表加依墓地和西沟墓地出土绿松石的散点聚集成团,且明显区分于白河、郧县、洛南、竹山、淅川五地的散点分布区域。综上结果表明新疆东部两处遗址的绿松石制品与中原东秦岭五处绿松石矿区所产矿料的成分差异较大,鉴于近年来新疆哈密发现与两处遗址同时代的绿松石采矿遗址,推测加依墓地、西沟墓地的绿松石制品其矿料来自中原地区的可能性较小。  相似文献   

20.
Morphology evolution of prior β grains of laser solid forming (LSF) Ti-xAl-yV (x 11,y 20) alloys from blended elemental powders is investigated. The formation mechanism of grain morphology is revealed by incorporating columnar to equiaxed transition (CET) mechanism during solidification. The morphology of prior β grains of LSF Ti-6Al-yV changes from columnar to equiaxed grains with increasing element V content from 4 to 20 wt.-%. This agrees well with CET theoretical prediction. Likewise, the grain morphology of LSF Ti-xAl-2V from blended elemental powders changes from large columnar to small equiaxed with increasing Al content from 2 to 11 wt.-%. The macro-morphologies of LSF Ti-8Al-2V and Ti-11Al-2V from blended elemental powders do not agree with CET predictions. This is caused by the increased disturbance effects of mixing enthalpy with increasing Al content, generated in the alloying process of Ti, Al, and V in the molten pool.  相似文献   

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