Microstructure Analysis and Properties of Anti-Reflection Thin Films for Spherical Silicon Solar Cells

Structure and properties of anti-reflection thin films of spherical silicon solar cells were investigated and discussed. Conversion efficiencies of spherical Si solar cells coated with F-doped SnO2 anti-reflection films were improved by annealing. Optical absorption and fluorescence of the solar cells increased after annealing. Lattice constants of F-doped SnO2 anti-reflection layers, which were investigated by X-ray diffraction, decreased after annealing. A mechanism of atomic diffusion of F in SnO2 was discussed. The present work indicated a guideline for spherical silicon solar cells with higher efficiencies.

Anti-Reflection Characteristics of Si Nanowires for Enhanced Photoluminescence from CdTe/CdS Quantum Dots

CdTe/CdS quantum dots（QDs） are fabricated on Si nanowires（NWs） substrates with and without Au nanoparticles（NPs）. The formation of Au NPs on Si NWs can be certified as shown in scanning electron microscopy images. The optical properties of samples are also investigated. It is interesting to find that the photoluminescence（PL） intensity of Cd Te/Cd S QD films on Si nanowire substrates with Au NPs is significantly increased,which can reach 8-fold higher than that of samples on planar Si without Au NPs. The results of finite-difference time-domain simulation indicate that Au NPs induce stronger localization of electric field and then boost the PL intensity of QDs nearby. Furthermore, the time-resolved luminescence decay curve shows the PL lifetime, which is about 5.5 ns at the emission peaks of QD films on planar, increasing from 1.8 ns of QD films on Si NWs to4.7 ns after introducing Au NPs into Si NWs.

Preparation and Drug-Release Property of Polycaprolactone (PCL)/Polyglycolic Acid (PGA) Composite Masterbatch with Drug of Tea Polyphenols (TPs)

In order to effectively control the drug-release rate of medical textiles,biodegradable polycaprolactone(PCL) and polyglycolic acid(PGA) were blended at various mass ratios to prepare composite masterbatches for medical textiles.The surface morphology and the chemical structure of the masterbatches were analyzed.The crystallization,mass losses,strengths and drug-release rates of the composite masterbatches at different PCL/PGA mass ratios were explored.The results show that the degradation rate of the PGA carrier is obvious higher than that of the PCL carrier,and PCL,PGA and the tea polyphenol(TP) drug just physically mix without chemical reaction.During the degradation,the strength of the composite masterbatches gradually decreases.In addition,the drug-release rates of composite masterbatches at different mass ratios are different,and the more the PGA in the composite masterbatches,the faster the drug release of the composite masterbatches.The drug-release rate of the composite masterbatches can be controlled by adjusting the contents of PCL and PGA.

ATPB超分散剂的合成及其在ABS/炭黑复合体系中的应用

以端羟基聚丁二烯和N,N-二甲基氨基丙胺为原料,采用两步亲核取代反应制备了含有聚丁二烯骨架和胺基末端结构的端胺基聚丁二烯(ATPB),利用傅里叶变换红外光谱仪、核磁共振氢谱仪表征其分子结构,结果表明,ATPB成功合成并达到预期分子结构。以ATPB为超分散剂,制备了丙烯腈-丁二烯-苯乙烯嵌段共聚物(ABS)和炭黑的复合材料,测试炭黑分散度、分散稳定性和复合材料力学性能。结果表明,合成的ATPB超分散剂对炭黑具有明显的分散效果和较好的分散稳定性,与未经分散的炭黑相比,体系分散度提高了65.8%。复合材料力学性能得到增强,拉伸、弯曲强度分别提升至45.56、78.31 MPa,冲击强度提高了15.7%,其值为7.50 kJ/m^(2)。

基于可低温加工SEBS的发泡母粒及微发泡热塑性弹性体的制备

以可低温加工的氢化苯乙烯-丁二烯嵌段共聚物(SEBS)为基体,将偶氮二甲酰胺(AC)发泡剂、助发泡剂和表面活性剂制备成基于SEBS的发泡母粒,并采用双螺杆挤出机将发泡母粒与动态硫化三元乙丙橡胶(EPDM)/聚丙烯(PP)热塑性弹性体材料(TPE)共混熔融挤出,制备了微发泡TPE材料。研究了SEBS引入量与发泡母粒添加量对微发泡TPE样品的密度、拉伸性能以及泡孔形貌的影响。结果表明,当SEBS的质量分数低于6%,发泡母粒的质量分数为3%时,制备的微发泡TPE材料具有较低的密度、较高的拉伸性能,且泡孔规整度达到最优。

增韧聚醚酰亚胺(PEI)复合材料的制备及性能研究

采用三元乙丙橡胶(EPDM)、自主创新研发的聚苯乙烯基炭化微球、聚醚酰亚胺为原料,通过挤出熔融共混法制得增韧聚醚酰亚胺复合材料。实验结果表明,当加入三元乙丙橡胶用量为15份时,其冲击强度、断后伸长率与纯料进行对比,分别提高了200.0%、272.7%,达到了提高聚醚酰亚胺抗冲性能的目的;DSC测试结果表明,在聚苯乙烯基炭化微球作用下,三元乙丙橡胶与聚醚酰亚胺具有一定的相容性;TGA测试结果表明,聚醚酰亚胺复合材料加工温度在430℃范围内热稳定性良好;SEM冲击断面表明,EPDM/聚苯乙烯基炭化微球母粒料的加入对聚醚酰亚胺具有增韧效果,且粒子分布均匀。

175 dtex原液着色涤纶预取向丝的制备工艺

采用特殊工艺共混改性路线和在线添加黑母粒技术,研制开发175 dtex原液着色涤纶预取向丝(POY)。对切片和黑母粒的干燥工艺、过滤、纺丝的油嘴选型、冷却条件、卷绕成型等生产工艺进行了研究,确定了175 dtex原液着色涤纶POY的最佳制备工艺,制得的产品综合性能良好,满足后道客户加工要求。

涤纶染色和色母粒着色绒类产品碳足迹核算及评价

为了应对社会对披露碳足迹信息的要求,根据碳足迹核算标准,以1 t涤纶绒类产品为功能单位,分别计算涤纶染色绒类产品与涤纶色母粒着色绒类产品从摇篮到大门的碳足迹。结果表明:1 t涤纶染色产品从摇篮到大门的产品碳足迹为6483.8 kgCO_(2)e,1 t涤纶色母粒着色绒类产品从摇篮到大门的产品碳足迹为5217.8 kgCO_(2)e。相比同样功能的涤纶染色产品,每功能单位的涤纶色母粒着色绒类产品碳足迹减排率为19.5%。两款产品的碳排放主要来源于原料和能源部分。为降低涤纶绒类产品的碳排放,一方面可以采用低碳绿色原料或能源,另一方面改变加工方式和染色工艺。

无卤阻燃母粒及其改性纤维的制备和性能研究

以无卤阻燃剂为改性剂、大有光聚对苯二甲酸乙二酯(PET)切片为基体熔融挤出制得无卤阻燃母粒,并将其与半消光PET切片共混熔融纺丝得到阻燃PET预取向丝(POY),再经加弹得到阻燃PET拉伸变形丝(DTY),探究了加工工艺对阻燃母粒制备的影响,评价了阻燃母粒的物性指标和热稳定性,并研究了阻燃母粒添加量对纤维力学性能和阻燃性能的影响。结果表明:阻燃母粒的较佳制备工艺为阻燃剂质量分数40%、熔体温度265℃、螺杆转速200 r/min、切粒机转速35 Hz;阻燃剂在PET基体中均匀分散,加入后不影响PET切片的特性黏数和熔点等物性指标,且提高了PET的热稳定性和成炭能力;当添加的阻燃母粒质量分数为6%~12%时,制备的阻燃PET POY的力学性能与常规PET POY接近;当添加的阻燃母粒质量分数为10%时,制备的阻燃PET DTY具有优异的阻燃性能,极限氧指数达31.8%。

Isothermal Crystallization Behavior of Poly (ethylene terephthalate)/Carbon Black Masterbatch

Poly(ethylene terephthalate) (PET)/carbon black (CB) masterbatch was prepared by melt blending using a separate feeding technique and its homogeneous dispersion morphology was confirmed by transmission electron microscope (TEM). The Avrami and Hoffman-Lauritzen secondary nucleation theories were employed to analyze the effect of high CB content on crystallization kinetics of PET, providing theoretical support for the development of masterbatch with high content of functional components. The Avrami exponents,average values of n,for PET and PET/CB masterbatch are both greater than 3, which indicates three-dimensional growth of crystals. In addition,no significant evidence for regime transition of PET is found applying Hoffman-Lauritzen secondary nucleation theory,though such observations have been reported previously in the literature. Furthermore,appropriate U* value for PET is determined to be 12 800 J/mol. For PET/CB masterbatch,a transition from regime I to regime II around 225℃ is observed with appropriate U* value (12 800 J/mol) . This phenomenon is consistent with a transition point in plot of G versus Tc . The fold surface free energy σe (100. 3 mJ/m 2) of PET is much greater than that of PET/CB masterbatch (48. 3 mJ/m 2) ,which indicates heterogeneous nucleation effect of CB particles.

Preparation of Scratch-Resistant Nano-Porous Silica Films Derived by Sol-Gel Process and Their Anti-reflective Properties

Structural strengthening of the nano porous silica films has been reported. The films were prepared with a base/acid two-step catalyzed TEOS-based sol-gel processing and dip-coating, and then baked in the mixed gas of ammonia and water vapor. The silica films were characterized with TEM, AFM, FTIR, spectrophotometer, ellipsometer, and abrasion test, respectively. The experimental results have shown that the films have a nanostructure with a low refractive index and can form an excellent scratch-resistant broadband anti-reflectance. The two-step catalysis noticeably strengthens the films, and the mixed gas treatment further improves mechanical strength of the silica network. Finally the strengthening mechanism has been discussed.

Carboxylic Acids and Esters as Scaffold for Cavities in Porous Single Layer Anti-Reflective Coatings of Silica-Titania with Excellent Optical and Mechanical Properties

Anti-reflective (AR) single layer of silica-titania (SiO2-TiO2) coatings were obtained from sols containing pyromellitic dianhydride (PMDA) derivatives and Ti and Si precursors on glass substrate by dip-coating method. The coatings showed very high optical quality and the transmission was improved to up to 98.5%. Furthermore, the coatings also presented good mechanical stability.

水驻极母粒对熔喷聚丙烯流变与结晶性能的影响

为探索水驻极熔喷生产工艺最佳配比和熔融温度,在熔喷聚丙烯原料(熔融指数为1200 g/10 min)中混入2%~6%(质量分数)的水驻极母粒,对其熔体流变和结晶性能进行了测试研究。实验结果表明:水驻极母粒改性聚丙烯共混体系非牛顿指数(n)小于1,为假塑性流体;温度和剪切速率对共混体系表观黏度的影响显著,随着温度和剪切速率增大,共混体系的黏度呈下降趋势,驻极母粒添加含量(质量分数)低于4%时,有助于降低共混体系的表观黏度;共混体系的黏流活化能(ΔEη)随剪切速率增加而减小;而共混体系的ΔEη较纯聚丙烯有所增加,表明加入母粒后共混体系黏度对温度的敏感度增大;DSC结果表明,水驻极母粒加入有助于提高熔喷聚丙烯的结晶速率和结晶度。

Numerical-Experimental Analysis of the Coal Fracture Formation Mechanism Induced by Liquid CO_(2) Explosion

The highly inefficient simultaneous extraction of coal and gas from low-permeability and high-gas coal seams in deep mines is a major problem often restricting the sustainable development of coal industry.A possible way to solve this problem under deep and complex geological conditions is represented by the technology based on the phase-change induced explosion of liquid carbon dioxide.In this work,the mechanism of formation of the coal mass fracture circle resulting from the gas cracking process is theoretically analyzed.Numerical simulations show that a blasting crushing zone with a radius of 1.0 m is formed around the blasting hole.The radius of the sec-ondary expansion zone caused by the exploding gas is 2.0 m,and the extension limit of the explosion fracture is 2.3 m.The gas phase change explosion is influenced by the coal roadway driving face,the gas content index and the analytical index of coal shavings.Experiments conducted for comparison also lead to the conclusion that the initial gas emission is increased by 3.7 times from the 100-meter borehole in the original coal mass after coalbed gas explosion anti-reflection.

用于液晶聚芳酯纤维原液着色的色母粒制备

选用炭黑作着色剂,制备了用于液晶聚芳酯纤维原液着色的色母粒。通过对分散剂耐热性、分散剂用量及母粒生产工艺的研究,探讨了母粒最佳制备工艺。制备的色母粒中炭黑分散性良好,无黑点和气泡产生。色母粒熔点、黏度与纯树脂接近,两者相容性好。使用色母粒进行长时间纺丝,过程压力上升缓慢,连续纺丝时间长,纤维呈均匀的深灰色,力学强度损失低。

橡胶/白炭黑连续液相混炼胶在轮胎中的应用

介绍橡胶/白炭黑连续液相混炼胶(EVEC)的生产工艺,根据填料-聚合物相互作用的相关理论分析EVEC良好的填料分散性、较低的滞后损失、优异的抗湿滑性能和耐磨性能。经室内试验、场地测试和实车路试验证,用EVEC胎面胶制造的载重轮胎和轿车轮胎具有燃油消耗低、二氧化碳排放少、制动距离短和使用寿命长的特点,在安全、节能、舒适和耐磨性能等方面的优势显著。EVEC轮胎的经济效益和社会效益显著。

石墨烯改性中空涤纶短纤维生产工艺探讨

在大容量直接纺中空涤纶短纤维生产线上,通过在线添加装置添加石墨烯母粒对聚对苯二甲酸乙二醇酯(PET)熔体共混改性,生产5.50 dtex石墨烯改性中空涤纶短纤维,探讨了生产工艺对产品性能的影响。结果表明:在干燥温度160℃、干燥时间8 h的条件下,石墨烯母粒含水率达40μg/g;在PET熔体中添加质量分数为1.0%的石墨烯母粒共混改性后,PET熔体的特性黏数控制在0.645 dL/g;纺丝温度285℃、环吹风速3.4 m/s时前纺生产稳定,原丝具有良好的潜在三维卷曲;拉伸温度66℃、拉伸倍数2.80时后纺生产正常,产品的三维立体卷曲感强;5.50 dtex石墨烯改性中空涤纶短纤维的卷曲数为25 mm长度内6.5个,卷曲率为16.7%,轻负荷作用下的蓬松度为154 cm^(3)/g,重负荷作用下的蓬松度为28 cm^(3)/g,抑菌率为99.5%,保温率为94%,远红外发射率为92%,负离子释放量为5500个/cm^(3)。

色母对玻纤增强PBT激光吸收特性及打标效果的影响

将玻纤增强的聚对苯二甲酸丁二酯(PBT),分别与质量分数0.5%,1.0%,1.5%的蓝色色母及黑色色母粒子进行混合,通过模压机熔融注塑为2 mm的片材。利用分光光度计测试不同颜色及含量的色母粒子的PBT的反射率、吸光度等光学特性;利用差示扫描量热仪研究了色母填料对PBT的熔融分解行为的影响。并运用激光打标机对不同色母粒子的片材表面进行激光镭射,利用扫描电子显微镜对激光镭射后的片材表面进行微观形貌分析。结果表明,少量色母的加入会极大改变PBT的反射率及吸光度等光学特性,在900~1200 nm范围内,反射率对比:黑色色母料<蓝色色母料<纯PBT,吸光度对比:黑色色母料>蓝色色母料>纯PBT,且色母含量越高,PBT的吸光度越高。而色母填料的加入对PBT的熔融、热解等热学行为没有明显的影响。通过1064 nm的激光对PBT进行表面打标,纯PBT由于对波长下的激光吸收较低,无法产生烧蚀;而加入色母后,激光可以在PBT表面形成烧蚀标记,微观形貌下可观察到裸露出来的内部玻璃纤维;黑色色母相较于蓝色色母,更易引起PBT在激光打标时的发泡甚至烧蚀,形成打标标识;且色母含量越高,PBT烧蚀越严重。

渗透结晶型防水剂活性母料配方优化研究

为了配置一种新型的渗透结晶型防水剂,对防水剂的活性母料进行配方优化试验。采用四因素三水平的正交试验方法对水泥基渗透结晶型防水剂的活性母料进行抗渗试验,研究了氧化钙、甲基硅酸钠、聚合硫酸铁、葡萄糖酸钠的掺量对水泥基渗透结晶型防水剂抗渗性能的影响。结果表明4种活性物质氧化钙、甲基硅酸钠、聚合硫酸铁、葡萄糖酸钠均能提高抗渗性能,对试件抗渗性能的影响由大到小依次为葡萄糖酸钠、甲基硅酸钠、氧化钙和聚合硫酸铁。渗透结晶型防水剂的最佳配方为氧化钙26.8g、甲基硅酸钠35.6g、聚合硫酸铁7.3g、葡萄糖酸钠10g,其抗渗压力值较基准组提高了400%。为渗透结晶型防水剂的研究提供参考。

磷氮型无卤膨胀阻燃聚乙烯母粒的制备及应用

采用转矩流变仪研究了聚乙烯(PE)基体材料、弹性体(POE)、马来酸酐接枝PE(PE-g-MAH)和润滑剂对磷氮型无卤膨胀阻燃聚乙烯母粒加工性、阻燃性能和力学性能的影响,确定了母粒配方,利用双转子连续混炼机研究了阻燃母粒的生产加工工艺。将制备的母粒和PE DM187(LD607)按照PE:阻燃母粒=60:40的比例共混后直接注塑成样,制备阻燃聚乙烯材料。通过拉伸和冲击性能测试研究了阻燃聚乙烯的力学性能,通过垂直燃烧测试研究了其阻燃性能。研究结果表明,磷氮型无卤膨胀阻燃聚乙烯母粒的最佳质量配比为PE M2320/FR-1420/POE 8200/KT-12/PE蜡/GTM 100=19.7/70.0/4.0/4.0/2.0/0.3;生产工艺条件为熔体温度220℃、主机转速200 r/min、切粒转速300 r/min,在该配比和生产工艺条件下制备的阻燃母粒塑化较好、表面光滑、本色颗粒均匀,并且,共混后直接注塑得到的阻燃聚乙烯材料力学性能稳定,阻燃性能可达到V-0级(1.6 mm)。