应用平行因子分析和三维荧光分析法分辨萘、1-萘酚和2-萘酚

首次利用三维荧光分析法与RARAFAC算法相结合,在激发波长为220-300nm2(2nm为间隔）,发射波长为325-600nm(5nm为间隔）对萘、1-萘酚和2-萘酚体系进行了分辨研究,分辨结果与真实结果一致。该方法分辨速度快,易于编程实现,且分辨率高,解决了三者同时分辨难的问题,充分地说明了化学计量学在环境化学中具有广阔的应用前景。     

自模型曲线分辨法校正电感耦合等离子体原子发射光谱中严重谱线重叠干扰

对严重重叠的光谱干扰校正,采用较小间隔的光谱扫描测量,并用间隔扫描点的数据计算,可减小计算结果的误差,提高结果的准确性。本方法用于校正Nd359.259nm对Sm359.260nm和V328.939nm对Yb328.937nm谱线重叠干扰,得到了满意的结果。     

平行因子算法用于酪氨酸、色氨酸和苯丙氨酸的同时定性与定量测定

酪氨酸、色氨酸和苯丙氨酸是天然氨基酸中仅有的会发光的组分。本文将三维荧光分析法与平行因子（PARAFAC）算法相结合，在激发波长为205-290nm(5nm为间隔），发射波长为270-380nm（5nm为间隔）对该体系进行了分辨研究，分辨结果与实际浓度一致。该方法分辨速度快，易于编程实现，且分辨效率高，解决了三者同时分辨难的问题，进一步说明了化学计量学在生物化学中具有广阔的应用前景。     

VA族元素氢化物的紫外光解和多光子电离Ⅱ. PH3的多光子电离光谱

用染料激光器在波长为300-640 nm范围内扫描, 观察到PH_3的一系列多光子电离光谱。其中351-398 nm的近二十条谱带, 其能级间隔约263 cm~(-1), 拟归属于通过Ã态的(2+1)电离谱。在460-495 nm的弱谱, 428-452 nm的六条谱带和385-398 nm之间的四条谱带, 则分别认证为相应于经历了B, C和D态的(3+1)MPI光谱。求得B态的项值T_0≤60729 cm~(-1), D态的T_0≤75567 cm~(-1), 而D态的反演振动频率ω_2为510 cm~(-1).     

VA族元素氢化物的紫外光解和多光子电离——Ⅱ.PH_3的多光子电离光谱

用染料激光器在波长为300-640nm范围内扫描,观察到PH_3的一系列多光子电离光谱。其中351-398nm的近二十条谱带,其能级间隔约263cm~(-1),拟归属于通过(?)态的(2+1)电离谱。在460-495nm的弱谱,428-452nm的六条谱带和385-398nm之间的四条谱带,则分别认证为相应于经历了(?),(?)和(?)态的(3+1)MPI光谱。求得(?)态的项值T_0≤60729cm~(-1),(?)态的T_0≤75567cm~(-1),而(?)态的反演振动频率ω~2为510cm~(-1).     

交替三线性分解算法与反相高效液相-二极管阵列检测方法相结合同时测定苯二酚的位置异构体

 利用交替三线性分解算法与反相高效液相 二极管阵列检测 (RP HPLC DAD)相结合 ,在洗脱时间为1 0 86min～ 1 399min(间隔 1 / 1 50min)、紫外吸收波长为 2 68nm～ 2 98nm(间隔 1nm)时对苯二酚位置异构体的重叠及光谱体系进行了分辨研究。分辨结果与实际结果一致。同时测定了水溶液中共存的邻苯二酚、间苯二酚和对苯二酚的含量 ,回收率分别为 (1 0 0 1± 1 0 ) % ,(99 4± 1 4) % ,(1 0 0 5± 1 7) %。研究结果表明 :该方法定量快速准确 ,实验操作步骤简单 ,解决了在干扰物存在条件下三者很难同时分辨的问题。     

含柔性链段的苯并二噁唑类聚合物合成与表征

通过溶液缩聚反应,合成了一系列含有刚性苯并唑噁环和柔性脂肪链的刚、柔间隔聚合物.通过FT-IR1H-NMR 和 TGA 等方法对聚合物化学结构和热失重行为进行了表征.发现聚合物分子链中出现了微量未闭环结构,热分解温度有所降低.聚合物溶液的紫外吸收光谱的最大吸收从 PBO 的429 nm蓝移到 PBOC7 的291 nm,同时荧光 stokes 位移增大.     

含柔性链段的苯并二啞唑类聚合物合成与表征

通过溶液缩聚反应,合成了一系列含有刚性苯并啞唑环和柔性脂肪链的刚、柔间隔聚合物.通过FT-IR1、H-NMR和TGA等方法对聚合物化学结构和热失重行为进行了表征.发现聚合物分子链中出现了微量未闭环结构,热分解温度有所降低.聚合物溶液的紫外吸收光谱的最大吸收从PBO的429 nm蓝移到PBOC7的291 nm,同时荧光Stokes位移增大.     

meso-四[(4-苯乙烯氨基)苯基]卟啉合成及其波谱特点

以吡咯和对硝基苯甲醛为原料,经过环化、还原和缩合,合成了meso-四[(4-苯乙烯氨基)苯基]卟啉(TBAPP),通过UV-Vis、FT-IR、1H NMR及元素分析等对产物进行了表征,并对其荧光和电子顺磁共振特性进行了研究。 卟啉产物的EPR测定显示出游离基特征,表明卟啉分子的大π共轭结构对周边基团产生的自由基有稳定作用。 取代基对卟啉的紫外 可见吸收、光致发光及电子顺磁共振特性均有影响。 四席夫碱苯基卟啉TBAPP的Q带比前体四氨基卟啉（TAPP）和母体四硝苯基卟啉（TNPP）红移,而Soret谱带变化较小;TBAPP的440 nm光激发的最大荧光峰658 nm分别比TAPP蓝移5 nm和比TNPP红移9 nm;TBAPP的EPR精细结构比TAPP弱,而比TNPP强。     

微芯片上Ag2S电化学纳米开关的构筑及电学测量的初步研究

初步探索了利用电化学方法“自下而上”地构筑了Au/Ag/Ag2S-Au固体电化学纳米开关, 并确定了较适宜的开关工作条件. 小于1 nm的Ag2S-Au间隔是Ag2S开关器件的关键结构, 以保证电子的量子遂穿和间隔中Ag凸起的生长与收缩. 测量结果表明, Ag2S开关转换具有较好的可逆性和稳定性, 开关转换电流相差3个数量级以上.     

Photodestruction of fluorophores and optimum conditions for trace DNA detection by automated DNA sequencer.

Although automated DNA sequencers are becoming popular, their sensitivity in detecting DNA bands is still around 10(-17) mole/band. The sensitivity of a system depends on the laser power, labeling fluorophore, and the fluorescence-collecting yield. The emission and photodestruction cross-sections of the fluorophores are critical in optimizing the irradiated laser power and the migration speeds of DNA fragments to achieve high sensitivity. We investigated photodestruction cross-sections of various fluorophores to optimize the irradiation laser power. In addition, we used a cylindrical lens system to improve the fluorescence-collecting yield of a DNA sequencer using side entry laser irradiation. Fluoresceine isothiocyanate (FITC) commonly used in fluorescence studies, is very photo-destructive, the cross-section of the destruction being about 3.8 x 10(-20) cm2 in buffer solution while that of Texas Red is 1.5 x 10(-21) cm2. When the time for DNA fragments to transit through the irradiated region is 11 s, the optimum laser powers are 0.9 mW, with an Ar laser (488 nm) for FITC-DNA, and 18 mW, with an He-Ne laser (594 nm) for Texas Red DNA. We have developed a DNA sequencer, with a cylindrical lens system which improves the fluorescence-collecting efficiency by a factor of 4, and an He-Ne laser (5 mW). Although the sequencer uses a slab gel, an ultra-high sensitivity of 5 x 10(-20) mole/band (S/N-4) was achieved under optimized conditions.     

毛细管电泳-间接激光光热干涉检测方法研究

本文提出毛细管电泳-间接激光光热干涉检测新方法。采用吸收系数大、吸收波长与泵浦激光(He-Ne)波长匹配性能较好的亚甲蓝溶液为背景电解质溶液,加入乙醇减少了毛细管壁对亚甲蓝的吸附作用。并将间接光热干涉检测法用于氨基酸毛细管电泳分离检测,对赖氨酸检测限达5×10^-6mol/L(S/N=2).     

氧钒酞菁在激光光盘系统中的应用研究

氧钒酞菁在激光光盘系统中的应用研究董长征，沈永嘉，任绳武（华东理工大学精细化工研究所上海２００２３７）袁海俊（中国科学院上海光学精密机械研究所上海２０１８００）关键词：信息储存，激光光盘，功能染料，氧钒酞菁自１９７２年Ｐｈｉｌｉｐｓ公司推出激光光盘（...     

Low-Cost Colorimetric Measurement of Phosphate Trace Levels in Water and in Soil Solutions by the Collinear Photothermal Beam Deflection Method

Abstract

The collinear photothermal beam deflection technique with a c.w. AlGaAs semi-conductor diode laser (790nm) and He-Ne laser (630 nm) used as the pump and probe beam, respectively, has been combined with the molybdenum blue colorimetry to measure the level of orthophosphate in water and in soil solutions. A detection sensitivity of 0.1 mmol/m³ of PO^3- ₄ has been achieved with the present set-up.     

The damage repair role of He-Ne laser on plants exposed to different intensities of ultraviolet-B radiation

Light-grown broad bean (Vicia faba L.) seedlings were subjected to different intensities of UV-B radiation (0, 0.05, 0.15, 0.45, 0.90, 1.45 and 1.98 W m(-2)) for 7 h under photosynthetically active radiation (70 micromol m(-2) s(-1)) and then exposed to He-Ne laser (632.8 nm, 5.43 mW mm(-2)) radiation for 5 min or red light radiation for 4 h without ambient light radiation. When He-Ne laser radiated leaves were treated using lower intensity UV-B, the activities of superoxide dismutase (EC 1.15.1.1), ascorbate peroxidase (EC 1.11.1.11) and catalase (EC 1.11.1.6) improved significantly. Moreover, the UV-B-injured plants treated with laser light recovered faster from UV-B treatment because the concentration of malondialdehyde and the rate of electrolyte leakage from leaf disks reached control levels (no UV-B or laser treatment) early compared with those exposed only to ambient light or in dark conditions. Laser treatment, however, had no repair effect on seedling damage induced by higher UV-B radiation (1.45 and 1.98 W m(-2)), even with higher laser flux rates and longer laser treatment. In addition, the red light treatment had no repair effect on UV-B-induced damage. Meanwhile, the long-term physiological effect of He-Ne laser treatment on UV-B damaged plants was presented and evaluated. The results showed that the laser had a long-term positive physiological effect on the growth of UV-B-damaged plants. With the exception of the severe damage caused by higher UV-B radiation, a laser with the proper flux rate and treatment time can repair UV-B-induced damage and shorten the recovery time.     

Structural, spectral, optical and dielectric properties of copper and glycine doped LAHCl single crystals

Cu2+ and glycine doped L-arginine monohydrochloride monohydrate (LAHCl) single crystals were grown by slow solvent evaporation technique. The grown single crystals were confirmed by X-ray diffraction study and the interaction of dopants with LAHCl molecule was identified in Fourier transform infrared spectra. The crystalline perfection of pure and doped crystals was analyzed by high resolution X-ray diffraction studies. Vickers microhardness and UV-visible spectroscopy were carried out respectively to study the mechanical stability and optical transmittance of pure and doped LAHCl single crystals. He-Ne laser of wavelength 632.8 nm was used to measure refractive index and birefringence of grown crystals. The second harmonic generation efficiency was also measured for pure and doped LAHCl single crystals using Nd:YAG laser.     

Effect of light on calcium transport in bull sperm cells.

The effect of light on calcium transport was studied. Bull sperm cells were irradiated with an He-Ne (630 mm) laser and a 780 nm diode laser at various energy doses, and 45Ca2+ uptake was measured by the filtration technique. It was found that there is an accelerated Ca2+ transport in the irradiated cells, which means that laser light can stimulate Ca2+ exchange through the cell membrane. This may cause transient changes in the cytoplasmic Ca2+ concentration which, in spermatozoa, has a regulatory role in control of motility and acrosome reaction, and in other cells can trigger mitosis.     

Near-infrared range photorefractive composites based on poly(vinylcarbazole), multiwall carbon nanotubes, and fullerene C60 1

For composites based on poly(vinylcarbazole) and multiwall carbon nanotubes, photorefractive characteristics at 1064 nm have been studied in the presence and absence of fullerene C₆₀. It has been found that the introduction of fullerene C₆₀ provides an increase in the two-beam gain coefficient of a laser beam and a reduction in the time of hologram recording. The preillumination of the fullerene-containing layer with a continuous light from a He-Ne laser (633 nm) leads to an additional increase in the two-beam gain coefficient.     

Effect of laser dose and treatment schedule on excision wound healing in diabetic mice

The present study was undertaken to evaluate a He-Ne laser (632.8 nm; 7 mW; 4.02 mW cm(-2); 15 mm spot size) dose and the treatment schedule on diabetic wound healing in a mouse model. Circular wounds of 15 mm diameter were created on streptozotocin induced diabetic Swiss albino mice, and were uniformly illuminated with the single exposure of various He-Ne laser doses of 1, 2, 3, 4 and 5 J cm(-2) respectively. Further, the treatment schedule was also optimized by exposing the wounds with 3 J cm(-2) at 0, 24 h, 48 h postwounding. Contraction kinetics, mean area under the curve and the mean healing time of the wounds were computed along with the collagen and the glucosamine levels in the wound ground tissues at various postwounding treatment schedules. Results of this study indicated that the single exposure of 3 J cm(-2) laser dose applied immediately after the wounding caused a significant reduction in the mean area under the curve and the mean healing time along with the elevated levels of collagen and glucosamine contents in the tissue compared to the controls. In conclusion, He-Ne laser dose of 3 J cm(-2) applied immediately after the wounding has demonstrated optimum wound healing compared to the other doses and treatment schedules.     

Cytokine production after helium-neon laser irradiation in cultures of human peripheral blood mononuclear cells.

The effects of laser light on the immune system have not been extensively characterized. Low-power laser sources, such as the helium-neon (He-Ne) laser with a wavelength of 632.8 nm, have been found to produce photobiological effects with evidence of interference with immunological functions. We have investigated the effects of He-Ne laser irradiation on Ficoll-Hypaque-isolated human peripheral blood mononuclear cells (PBMC). Cultured cells were irradiated for various times at two selected intensities and then stimulated with different mitogens. The rate of incorporation of 3H-thymidine into the DNA of stimulated cells decreased with increasing energy density. The levels of interleukin-1 alpha (IL-1 alpha), interleukin-2 (IL-2), tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) in supernatants of the cultures were determined (irradiated either before or after stimulation). When stimulating cells after irradiation, significantly increased levels of all cytokines were detected after 30 min of irradiation (18.9 J cm-2), whereas after 60 min of irradiation (37.8 J cm-2) cytokine levels were found to be significantly decreased.