关于300D/32F扁平丝FDY工艺条件探讨

现在市场上的同质化产品太多,多样化面料价格居高不下,为满足客户需求和改善行业竞争模式,对涤纶扁平300 D/32 F工艺讨论.在生产中不断调整工艺参数,检测产品品质.通过优化工艺可以稳定生产出AA率高的异形扁平FDY 300D/32F全消光丝.     

气溶胶对远红外激光辐射的衰减规律研究

计算分析了10.6μm波长远红外激光辐射在不同能见度条件下的大气气溶胶中水平传输的衰减系数、有效传输距离以及斜程传输时的透过率变化规律,对比分析了远红外激光辐射在1.0g/m3的高浓度酸雾和油雾气溶胶中的传输能力。根据Mie理论计算了直径为0.5～40μm的水溶性大气气溶胶和尘状气溶胶粒子对10.6μm激光的散射效率因子、吸收效率因子和消光效率因子。结果表明:气溶胶的消光系数越大、大气能见度越低,大气气溶胶对远红外激光辐射的衰减越严重;在1.0g/m3的高浓度酸雾和油雾气溶胶中远红外激光辐射的有效传输距离只有20～50m。水溶性大气气溶胶和尘状气溶胶粒子对10.6μm激光辐射的衰减机理基本相同,其中散射作用居于主导地位并且平均直径大于5μm的气溶胶粒子对10.6μm远红外激光辐射具有显著的衰减作用。     

Ag/SiO_2/Ag组成的三角形纳米柱的光学及传感特性

研究了一种Ag/SiO2/Ag组成的三角形纳米柱的LSPR消光光谱特性及其传感特性.时域有限差分（FDTD）法计算结果表明,三棱柱结构在中间夹层SiO2后,消光光谱峰值出现红移现象,并伴随着折射率灵敏度的增加.随着中间介质层厚度的增加,上下两层金属间表面等离子体耦合逐渐减弱,消光光谱峰值红移速度减慢.当介质层厚度为60nm时,金属层间的表面等离子体耦合消失,消光光谱与折射率灵敏度不再发生变化.对于实际制作时可能出现尖角钝化的三棱柱结构,中间介质层仍然表现出对其光学及传感特性的良好的调节作用.     

Adolescents exhibit behavioral differences from adults during instrumental learning and extinction.

Adolescence is associated with the development of brain regions linked to cognition and emotion. Such changes are thought to contribute to the behavioral and neuropsychiatric vulnerabilities of this period. We compared adolescent (Postnatal Days 28–42) and adult (Postnatal Day 60+) rats as they performed a simple instrumental task and extinction. Rats were trained to poke into a hole for a food-pellet reinforcer. After six days of training, rats underwent extinction sessions in which the previously rewarded behavior was no longer reinforced. During extinction, we examined the effects of continued presentation of a cue light and food restriction. Adults and adolescents exhibited similar performance during training, although adolescents made more task-irrelevant pokes, consistent with increased exploration. Adults made more premature pokes, which could indicate a more exclusive focus on the task. During extinction, adolescents made more perseverative (previously reinforced) pokes than adults. This behavior was strongly modulated by the combination of motivational factors present (food restriction and cue light), indicating that adolescents were differentially sensitive to them. Furthermore, food restriction induced greater open-field activity in adolescents but not in adults. Thus, as the neural circuitry of motivated behavior develops substantially during adolescence, so too does the behavioral sensitivity to motivational factors. Understanding how such factors differently affect adolescents may shed light on mechanisms that lead to the development of disorders that are manifested during this period. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

三叠系—侏罗系环境变化及界线研究方法综述

三叠纪—侏罗纪之交全球发生了一系列不同程度的生物及环境变化,包括温度上升,气候从干旱过渡到潮湿,海平面快速的海退-海进以及大规模的生物灭绝事件等。相关地质及地球化学方法对全球各地质剖面进行的大量研究认为,中部大西洋岩浆省（CAMP）的密集火山活动所产生的大量CO₂及其他火山气体的排放最有可能造成生物灭绝及环境变化。同时,大量轻质碳的输入也扰乱了全球碳循环,造成碳同位素值在该时期出现不同程度和不同次数的负偏移。目前,三叠系—侏罗系界线的研究主要依据生物地层学（如菊石和孢粉化石带的划分）,结合地球化学（如碳同位素标定、元素分布分析）,综合数据建立地质模型等方法进行。中国三叠系—侏罗系界线研究还很薄弱,主要以生物地层学为主,缺乏地球化学数据。通过总结国际三叠系—侏罗系界线研究尤其是研究方法,对中国三叠系—侏罗系界线研究提供参考。     

铜锌合金粉的表面改性及其抗氧化性研究

选用了正硅酸四乙酯和硅烷偶联剂KH-550两种材料对铜锌合金粉进行表面改性,通过扫描电镜,热分析仪,红外光谱仪等仪器表征其抗氧化性和红外消光能力.结果表明,铜锌合金粉及其改性物的氧化放热峰温 (T_p) 分别为332.2,330.1和302.3 ℃,增重率分别为16.5%,13.7%和14.6%.在3~5 μm,两种改性物的质量消光系数 (α_λ) 分别为0.82和0.63 m²/g;在8~14 μm,α_λ值分别为0.69和0.53 m²/g.与纯铜锌合金粉相比,改性物的红外消光能力下降有限,抗氧化性提高.     

AN INVESTIGATION ON THE OPTICAL PROPERTIES OF CARBON BLACK,FULLERITE, AND OTHER CARBONACEOUS MATERIALS IN RELATION TO THE SPECTRUM OF INTERSTELLAR EXTINCTION OF LIGHT

ABSTRACT

In this work, the optical properties in the UV-VIS of three carbon blacks having specific surface area from 145 to 7?m²/g and produced with furnace or thermal processes have been studied. The results have been compared to the optical properties (in the same spectral range) of C₆₀ fullerene photopolymer, to fullerite i.e., the carbon soot containing fullerenes and to a sample of carbonaceous matter containing carbyne. The scope of the work was to verify if any of the carbonaceous matter studied was able to match the interstellar extinction spectrum which shows a “bump” at 217.5?nm and which was originally attributed to interstellar graphitic particles. None of the materials studied has shown a peak at 217.5?nm. All the carbonaceous materials studied show maxima of absorption from 252 to 267?nm with the exclusion of C₆₀ photopolymer which has a completely peculiar and different spectrum from all other materials with three maxima at 271, 389 and 510?nm. All the carbon materials studied do not match the 217?nm peak, hence, cannot be considered the carrier of the interstellar “bump” but may be present in some circumstellar shells of late type stars, where the peaks at 240–250?nm have been recorded and attributed to a more ordered and partially graphitized carbonaceous matter. In the discussion, the matrix effect, the particle size, and the clumping of the material studied have been considered as cause of the shift of the peak to longer wavelength.

The carbon black samples have also been extracted with pentane or ethanol and the polycyclic aromatic hydrocarbons (PAH) identified have been discussed in the frame of recent works and in relation to the role that they play in the interstellar medium as potential carriers of the diffuse interstellar bands (DIBS).     

Size dependent optical properties of LaB6 nanoparticles enhanced by localized surface plasmon resonance

Lanthanum hexaboride nanopartieles, with high emission electrons in cathode materials and peculiar blocking near infrared wavelengths, were applied for many aspects. Based on the quasi-static approximation of Mie theory, the size dependent optical prop- erties of LaB6 nanoparticles were researched, such as refractive index n（ω）, extinction coefficient k（ω）, reflectivity R（ω）, absorption coefficient a（ω）, and electron energy loss L（ω）. Due to the localized surface plasmon resonance （LSPR）, the extinction coefficient k（ω） and absorption coefficient a（ω） depended on the size, and the LSPR peaks red-shifted with sizes increased, which was different from that of bulk materials. In addition, electron energy-loss spectrum L（co） showed electrons oscillation reinforced, since electrons absorbed the photon energy and generated resonance. Further, reftectivity R（ω） and refractive index n（ω） indicated that the light in near infrared region could not be propagated on the surface of LaB6 materials, which exhibited metallic behaviors. So the resonance peak of LaB6 nanoparticle was located in near-infrared region, making use of this property for solar control glazing and heat-shielding application.     

Effect of Particle Size Distribution of Calcined Diatomites on the Extinction Performance

Calcined diatomite was first investigated as matting agent for formulating high-performance coating. Jet milling and sieving or sedimentation methods were employed to obtain rational particle size distributions. It was found that the optimal size distribution of the particles with the diameters of D₁₀ = 2.54 µm, D₂₅ = 5.04 µm, D₅₀ = 9.74 µm, D₇₅ = 18.80 µm, and D₉₀ = 31.66 µm showed the best extinction performance, with the gloss and extinction being 2.9 and 3.3 and 32.6% and 50.7% determined at incidence angles of 60° and 85°, respectively.