SR-UV型标准太阳紫外光谱辐射计的研制

SR-UV型标准太阳紫外光谱辐射计是为国家气象部门研制的，用于测量太阳紫外光谱辐射的标准仪器。本文叙述了该仪器的组成结构和工作原理，并给出了该仪器的性能指标。经过特殊光路设计，该仪器能够进行光谱辐射亮度和照度测试。如果增加光栅和截止滤光片，仪器的波长可拓展到可见和近红外波段，适用于航空航天和地物遥感等领域。     

紫外光辐照聚乙烯膜接枝丙烯酸的研究

以低密度聚乙烯膜为接枝基材，丙烯酸为接枝单体，考察了紫外光辐照聚乙烯膜接接反应的主要影响因素，以及接权后聚乙烯膜的力学性能变化。     

激光危险辐射的检测与报警

激光危险辐射量的检测报警是激光安全工作中的重要内容。激光危区检测报警仪是一种对平均辐照度，重复脉冲峰值辐照度和单脉冲辐照量测量报警的仪器，该仪器配备光电型、热释电型和量热型三种传感器。     

紫外光辐射交联甲基乙烯基硅橡胶/线性低密度聚乙烯热塑弹性体的性能

在光引发剂存在的条件下,利用紫外光对甲基乙烯基硅橡胶/线性低密度聚乙烯(MVQ/LLDPE)热塑弹性体进行辐射交联改性,通过凝胶含量、力学性能和热延伸测试,以及差示扫描量热法(DSC)和扫描电镜(SEM)分析,考察其交联特性及相关力学性能。实验结果表明,凝胶含量随光引发剂用量先增加后减小,在1%时出现极大值88%。凝胶含量随着辐照时间快速增加,当辐照时间为6s时,凝胶含量可以达到89%。随着辐照时间的延长,材料的拉伸强度显著提高,而断裂伸长率和热延伸率逐渐下降。扫描电镜(SEM)照片表明,紫外光交联提高了MVQ和LLDPE两相的相容性。差示扫描量热法(DSC)结果表明,紫外光交联可使材料的熔点从124.6℃下降到112.3℃,熔融焓由39.09 J/g下降到32.22 J/g。     

从参考太阳电池到太阳电池组件的量值传递技术研究

为实现太阳电池光电参数测量条件的一致性,进而保证测量数据的准确性、实验室间测量数据比对及互认的公正性,该文通过对太阳电池的开路电压温度修正、短路电流温度修正、太阳辐照强度修正等量值传递技术的研究,完成参考太阳电池在标准状态(STC)下的量值传递到室外自然环境下的太阳电池组件,实现对非标准条件下太阳电池组件光电参数的STC修正。太阳电池组件修正后的开路电压值、短路电流值与STC条件下的开路电压值、短路电流值相对偏差分别为-0.95%、0.58%。该量值传递技术及其方法为非STC条件下太阳电池组件光电参数实验室间比对及互认提供可能。     

聚乙烯对γ吸收剂量测量的影响研究

研究了聚乙烯材料对于重铬酸银化学剂量计测量γ吸收剂量的影响.通过将平均分子质量在20万~30万u区间的聚乙烯放置于重铬酸银化学剂量计中制备为样品剂量计,分析其对于γ吸收剂量测量的影响.实验结果表明,样品剂量计与标准剂量计的比对偏差小于1.9%,样品剂量计测量数据平行偏差小于1%,且样品剂量计测量数据与辐照时间线性相关系数达0.999 7.说明聚乙烯材料在1 004~44 00Gy剂量范围内对重铬酸银化学剂量计测量结果影响很小,可以用聚乙烯材料替代玻璃安瓿制作剂量计测量标准玻璃剂量计无法测量的辐照部位,以保证产品、试件γ辐照吸收剂量的精确测量.     

人工气候试验装置对自然气候模拟性的评价方法

用红外光谱法跟踪聚乙烯标准参考片气候曝露过程的分子结构变化，发现其羰基生成与链端乙烯基的增长线性相关，但斜率ｔｇα随曝露环境而变，称α为气象综合作用角。研究证实，这个描写曝露膜分子结构变化的参数能够用来表征聚合物曝露环境的气候特性和评价人工气候箱对自然气候的模拟性。在统计分析广州３０年地面气象记录的基础上，评议市售气候箱仿造自然气候的能力与局限。建议到阳光下试验，经济又可靠。     

可见分光光度计透射比示值误差对测量结果的影响

透射比示值误差是指仪器透射比测量值与被测样的实测值之差.误差来源包含系统误差和随机误差,即仪器结构、光电转换特性和测量中环境变动,仪器不稳、读数误差.所以仪器在测量中存在一个与光辐射功率大小无关的绝对不确定量,而且对仪器的分析测试结果有影响,这样对被测浓度的结果也有影响.     

新型精密光电高温计

一、引言目视光学高温计是高温温标量值传递的主要标准器。但是由于以人的眼睛作为探测器及仪器的结构缺陷,使测量精度受到一定限制。因此,为提高量值传递及高温测量的精度,我们研制成功了光电高温计,取得良好的效果。该光电高温计,在900℃～2000℃范围内,其测温灵敏度可达0.1℃～0.2℃。测量准确度均为±1℃～1.5℃。二、光电高温计工作原理光电高温计的测温方法与目视光学高温计一样,它是应用光测高温技术进行测量的。本仪器的工作原理如图1所示。被测温的     

1MeV电子加速器辐照剂量的测量

目前吸收剂量的测量方法有多种,对低能电子束吸收剂量进行测量时,由于受到电子束穿透深度、热效应、动态加工等因素的影响,可用方法很少,通常用显色薄膜剂量片进行测量.本文采用FWT-60-00薄膜显色剂量片测量1MeV低能电子束进行辐照加工时的吸收剂量,研究了吸收剂量与束流强度、辐照时间、束下装置运行速度的关系,测量了材料中吸收剂量的深度分布,并对加速器能量进行了校正.结果表明:在相同的辐照时间和电子能量下,吸收剂量随束流的增加线性增长;速度较高时,吸收剂量与小车速度也呈现出良好的线性关系.     

茂金属聚乙烯(mPE-1)的非等温结晶行为

对茂金属聚乙烯(mPE-1)和传统的Ziegler-Natta聚乙烯(PE7042)的非等温结晶行为进行了研究.用DSC测试了两种聚乙烯的非等温结晶过程,采用Jeziorny法、莫志深法和Gupta法等对所得数据进行了分析.结果发现,mPE-1的结晶速率比PE7042低.在实验范围内,两种物料的非等温结晶动力学符合莫志深方程,并给出了动力学参数F(T)和a值.     

Photo- and Bio-Degradation Processes in Polyethylene,Cellulose and their Blends Studied by ATR-FTIR and Raman Spectroscopies

Polyethylene, cellulose and their blends with different compositions (5–30% cellulose content) were exposed to UV radiation or composted in soil for bio-degradation. Both types of degradation were carried out under laboratory conditions (room temperature, air atmosphere). The course of degradation processes has been studied using ATR-FTIR and Raman spectroscopies. There are practically no changes in spectra of photo- or bio-degraded pure PE films and cellulose powders. In contrast, the PE/cellulose blends are less stable than pure components and the processes of photodegradation seem to depend on blend composition and irradiation time. Prolonged UV exposure (100 h) leads to efficient photo-oxidation of blends studied. Biodegradation effect was also pronounced in PE films containing 30% cellulose.Spectroscopic measurements were performed during EU Marie Curie Training Site Fellowship at University Bordeaux1 (France).     

Noise of piezoelectric accelerometer with integral FET amplifier

Since significant progress has been achieved in the development of low-noise piezoelectric (PE) accelerometers with integral FET amplifiers, detailed noise analysis of the system PE transducer-FET amplifier, and obtaining the engineering formula for its noise floor has become vital. As a result of this analysis, the formula for the noise floor of PE accelerometers in terms of acceleration spectral density is obtained at wide frequency band. Noise floor of the low-noise PE accelerometer comprising low-noise JFET charge amplifiers with some particular parameters of the PE transducer and the JFET amplifier was measured. The theoretical and experimental curves of the PE accelerometer's noise floor have a good correlation with each other at frequencies from 1 Hz to 10 kHz. The contribution of the different noise sources to the overall noise floor is shown. Those noise sources include the mechanical-thermal noise and electrical-thermal noise of the PE transducer and all main noise sources of FET amplifiers: the thermal noise voltage of the FET biasing resistor, the thermal noise of the series resistor between the PE transducer and the gate of the FET, the channel thermal noise voltage, the 1/f noise voltage, and the shot noise current in the gate circuit. At low frequencies, the f/spl les/50 Hz noise floor is determined mainly by the FET biasing resistor's thermal noise and the PE transducer's electrical-thermal noise. At frequencies from about 50 Hz to about 1 kHz, the contribution of the PE transducer's electrical-thermal noise dominates over the amplifier's noise sources by a factor of less than 2. At frequencies above 1 kHz, noise floor is determined mainly by the JFET channel thermal noise and the PE transducer's electrical-thermal noise.     

Controlling the red boundary of the tunneling photoeffect in nanodimensional carbon structures in a broad (UV-IR) wavelength range

The tunneling photoeffect (PE) has been studied in a microdiode with an electrostatic field localized at an emitter based on a nanodimensional carbon structure. It is established that, when the carbon nanoemitter is exposed to laser and LED radiation photons of low energy (below work function) in the spectral range from near-UV (380 nm) to near-IR (1150 nm) at micro- and milliwatt optical power, a tunneling photocurrent can be initiated by controlling the electric field strength in the emitter-anode gap. The observed phenomenon can be adequately interpreted using a modified Fowler-Nordheim equation for non-equilibrium photoelectrons. Specific features of the construction and operation of photodetectors based on the tunneling PE with a controlled long-wavelength threshold (red boundary) of photoelectron emission are considered. The bandwidth of photoelectron emitters is evaluated, and the possibility of their operation in the wavelength range from UV up to far-IR is predicted.     

用于PE材料印刷的UV固化油墨的研制

研制了用于PE材料印刷的UV固化油墨,探讨了预聚物、活性单体、光引发剂对UV油墨的固化速度、附着力及耐溶剂性的影响,得出了油墨的最佳配方(以质量分数计)为:PUA 25%,PEA 25%,TMPTA 15%,NPGDA 15%,TPO 6%,炭黑8%,消泡剂3%,分散剂3%。按该配方配制的油墨,固化时间仅需8s,附着力等级为3级,耐溶剂性能良好,是一种适宜于PE基材印刷的UV固化油墨。     

不同类型包装膜对胡萝卜的保护效果研究

目的 以鲜切胡萝卜作为包装对象,研究聚乙烯（PE）薄膜、聚乳酸（PLA）薄膜、笼型聚倍半硅氧烷（POSS）改性PLA薄膜、硅橡胶（SR）薄膜以及改性SR薄膜对胡萝卜保护效果的差异。方法 通过傅里叶红外技术和紫外-可见光谱技术对包装膜的结构和性能进行检测,并测定不同包装下胡萝卜素含量的变化及胡萝卜的质量损失率。结果 不同类型的包装膜对鲜切胡萝卜的保护效果不同,尤其是胡萝卜素的保留率有较大差异。改性SR膜的紫外光谱透过率低,其对鲜切胡萝卜的胡萝卜素的保护功能最佳,水分保有率也较高;PE薄膜的紫外透过性高,对胡萝卜素的保护功能较差,但包装的鲜切胡萝卜质量损失率最小;POSS-PLA薄膜和PLA薄膜对胡萝卜素的保护作用居中,鲜切胡萝卜质量损失率高。结论 在实际包装应用中可以考虑将改性SR薄膜与PE薄膜组合使用。     

不饱和硅烷熔融挤出接枝聚乙烯的研究

采用熔融挤出法对低密度聚乙烯进行硅烷接枝,然后在催化剂二月桂酸二丁基锡存在进行水解交联,对接枝产物的熔体流动速率和交联样品的凝胶率的影响因素进行了系统的研究,接枝单体为乙烯基三乙氧基硅烷,主要引发剂为过氧化二异丙苯。     

聚醚/二苯甲酮侧基聚硅氧烷的膜形貌及亲疏水行为

用原子力显微镜AFM等仪器研究了单晶硅表面聚醚(PE)/二苯甲酮衍生物(UV)侧基聚硅氧烷PE-PUVSi的膜形貌及亲、疏水特性,探讨了空气湿度对PE-PUVSi膜形貌及表面性能的影响。结果表明,在单晶硅表面PE-PUVSi形成的硅膜呈非均一、微观相分离结构,其中UV侧基以直立纤细尖峰态分布在聚硅氧烷膜表面,而亲水性PE侧基则卷曲堆积成峰包。将PE-PUVSi硅膜在相对湿度(RH)为97%的空气中放置2.5 h,PE-PUVSi膜表面因吸附水而亲水性增加,其原有的纤细尖峰消失,而且膜表面平均粗糙度降低。     

Adhesion of PE modified by capacitively coupled radio frequency plasma-induced graft polymerization of glycidyl methacrylate

A graft polymerization of glycidyl methacrylate (GMA) on the pretreated polyethylene (PE) sheet samples by oxygen capacitively coupled radio frequency (RF) plasma was carried out to improve the adhesive properties of PE. The PE samples were treated with a RF power of 200 W for a treatment time of 40 s and then exposed to an oxygen atmosphere for a saturation time of 10 min. The grafting of the plasma pretreated PE performed in an aqueous GMA solution with the monomer concentration from 20 vol.% to 100 vol.% at a temperature from 20°C to 90°C for a reaction period up to 50 h. The optimum wettability of the graft polymerized PE surface with the concentration of 40 vol.% at the temperature of 70°C and for the time of 24 h was obtained as the static contact angle decreased from 104.2° for the original PE to 67.6° for the graft polymerized. After the graft polymerization, a strong absorption peak of C-O bonding was shown at 1050 cm⁻¹ in Fourier transform infrared spectrum, indicating an introduction of epoxy groups on the graft polymerized surface. Correspondingly, the surface roughness (Ra) increased from 0.137 μm for the original PE to 1.660 μm for the graft polymerized. The maximal lap adhesive strength of the graft polymerized PE samples lapped using a mixture of epoxy resin and curing agent was achieved to about 160 N·cm⁻². The fractured surfaces by tearing of the PE sheet matrix were observed on the tensioned PE samples due to the higher adhesive strength than that of the PE matrix.     

HPB－b－PMMA增容PVC／PE共混物球晶和结晶行为研究

以小角激光散射（ＳＡＬＳ）和广角Ｘ光衍射（ＷＡＸＤ）技术，测定了氢化聚丁二烯－聚甲基丙烯酸甲基嵌段共聚物（ＨＰＢ－ｂ－ＰＭＭＡ）增容的聚氯乙烯（ＰＶＣ）和聚乙烯（ＰＥ）共混物的球晶形态和结晶度。从该共混物中ＰＥ的结晶状况得出，增容剂ＨＰＢ－ｂ－ＰＭＭＡｄ在降低ＰＥ结晶能力、增加ＰＥ／ＰＶＣ界面粘合并形成ＰＶＣ和ＰＥ相间的部分相容性有着重要的作用。