HVOF制备WC-12Co太阳能选择性吸收涂层性能的研究

本文选用微米、亚微米和纳米结构三种WC-12Co金属陶瓷复合材料,采用超音速火焰喷涂方法（HVOF）制备了金属陶瓷太阳能选择性吸收涂层,测量了WC-12Co太阳能选择性吸收涂层的吸收率和发射率,并探讨了制备工艺、粉末中WC颗粒尺寸和涂层厚度对涂层性能的影响。     

预制层结构对CZTS薄膜微观组织和光学性能的影响

研究了叠层顺序对磁控溅射沉积铜锌锡硫(CZTS)吸收层的微观结构、表面形貌和光学性能的影响.试验结果表明:当预制层结构为Cu/ZnS/SnS2时,制备的CZTS薄膜在(112)晶面具有择优生长取向,并具有较好的结晶一致性,在288,335和368cm-1处呈现出特征拉曼(Raman)峰,薄膜表面晶粒较大、形状规则、薄膜空隙较少、比较致密,可见光范围内的吸收系数较高,光学带隙1.5eV,适合作为CZTS薄膜太阳能电池的吸收层;当预制层结构为SnS2/Cu/ZnS和ZnS/SnS2/Cu时,由于在预制层硫化过程中造成一定的Zn和Sn流失,使CZTS薄膜中含有CuS杂相,导致薄膜表面质量下降,禁带宽度增加,不适合做CZTS薄膜太阳能电池的吸收层.     

太阳能选择性吸收涂层的研究进展

太阳能是一种取之不尽用之不竭的清洁能源,通过高吸收率的太阳能选择性吸收涂层对可见光的吸收,能够把低品位的太阳能转换成高品位的热能.因此,制备高效的太阳能选择性吸收涂层是太阳能热利用中的关键技术.该文作者对目前国内外有关太阳能选择性吸收涂层的研究工作和最新进展进行介绍,综述目前国内外研究较多的几类选择性涂层,并总结了各种涂层的制备方法及其优缺点,希望为制备高吸收率太阳能选择性吸收涂层的研究提供有益的参考.     

w(Al_2O_3)/w(SiO_2)对烧结液相生成的影响研究

通过研究w(Al_2O_3)/w(SiO_2)对烧结液相生成的影响及分析实际烧结生产中烧结矿w(Al_2O_3)/w(SiO_2)不同范围对转鼓强度的影响,得出烧结配料w(Al_2O_3)/w(SiO_2)控制在0.300~0.355有利于烧结矿质量的提高。在此基础上,进一步探讨了马钢烧结配料w(Al_2O_3)/w(SiO_2)应该控制的水平及3个炼铁总厂烧结矿现w(Al_2O_3)下w(SiO_2)适宜的控制范围,并提出了针对性的调整建议。     

中高温金属／陶瓷型光谱选择吸收涂层的研究进展

太阳能选择吸收涂层是一种特殊的表面,在0.3～2.5μm太阳光谱范围内具有尽可能高的太阳吸收能力,同时在3～25μm红外波长范围内有尽可能低的热辐射能力.在太阳能热利用中,它能把太阳能富集起来,提高太阳能光热转换效率.近年来,太阳能的中高温利用日益成为人们关注的焦点.系统介绍r选择性吸收涂层的吸收机制、制备工艺,同时对国内外选择吸收涂层的现状做了综述.最近,对金属复合氧化物选择吸收涂层的研究有了新的进展,这类涂层在非真空、高温条件下具有较好的光学性能,且热稳定性好,有望进一步推动中高温太阳能吸收涂层的发展.     

粉末法制备太阳能电池Cu2ZSnS4薄膜吸收层

使用感应熔炼法制备Cu-Zn-Sn合金,并利用单辊甩带制备连续均匀的Cu-Zn-Sn合金薄带.球磨Cu-Zn-Sn合金薄带后和硫粉混合制成粉末前驱体,再将粉末前驱体涂敷在钠钙玻璃基体上在H2 S(g)和N2 S(g)气氛中退火,得到太阳能电池薄膜吸收层用材Cu2ZnSnS4.利用X.射线衍射仪(XRD)、扫描电镜(SEM)和能谱仪(EDS)对Cu-Zn-Sn合金薄带及Cu2ZnSnS4薄膜进行分析和表征,并利用可见光.紫外分光光度计测量Cu2ZnSnS4薄膜的吸收率和透光率.结果表明:使用单辊甩带法可以制备出成分均匀的脆性合金薄带,薄带厚度为6～10 μm.在N2 S(g)气氛下400℃退火后可制成比较纯净的具有锌黄锡矿结构的Cu2ZnSnS4薄膜,其禁带宽度为1.61 eV.     

质量分离的双离子束沉积法生长CeO2(111)/Si薄膜

利用一种全新的薄膜生长技术-质量分离的双离子束沉积技术,在较低温度(400℃)下对CeO2(111)/Si(100)薄膜的生长进行了研究.两束离子的比例以及离子束的能量对薄膜的成分和晶体质量有很大影响,较高能量(300eV)的离子束对薄膜有轰击作用,并有助于薄膜的择优取向生长.在400℃时,制备了CeO2(111)/Si(100)单晶薄膜.     

表层涂碳MlNi_(3.93)Co_(0.46)Mn_(0.27)Al_(0.34)/Co_3O_4CeO_2复合贮氢合金电极制备及电化学性能

通过分层涂浆制备表层涂碳的MlNi_(3.93)Co_(0.46)Mn_(0.27)Al_(0.34)/Co_3O_4CeO_2电极,并建立表层涂碳的MlNi_(3.93)Co_(0.46)Mn_(0.27)Al_(0.34)/Co_3O_4CeO_2电极反应机理模型。物理表征结果表明,活性碳(AC)具有高比表面积,为二维结构,贮氢合金呈块状固体,为单相的CaCu5型六方结构;电化学测试结果表明,活性碳形成双电层的同时也作为导电剂在MlNi_(3.93)Co_(0.46)Mn_(0.27)Al_(0.34)/Co_3O_4CeO_2电极表面形成导电网络,可改善贮氢合金电极的电化学性能,在0.2C充放电下,放电比容量292.6mAh·g-1,以1500mAh·g-1倍率放电时,高倍率放电性能(HRD值)为82.5%,循环100次后容量保持率95.91%,在50%DOD下,氢扩散系数及交换电流密度依次为4.7×10-11cm2·s-1,315.6mA·g-1,相比于未涂炭的MlNi_(3.93)Co_(0.46)Mn_(0.27)Al_(0.34)/Co_3O_4CeO_2电极,分别提高了2.4mAh·g-1、20.94%、5.53%、38.2%、34.5%。     

m(MgO)/m(Al_2O_3)对铁矿粉烧结矿相组成的影响

在准化学平衡条件下,通过相平衡实验研究了不同的m(MgO)/m(Al_2O_3)对含两种类型的Al_2O_3的铁矿粉烧结矿相组成的影响。利用X射线衍射及扫描电镜分别对试样进行了矿相组成分析和显微结构观察。实验结果表明:当温度为1300℃、二元碱度R=2.0时,含两种类型的Al_2O_3的铁矿粉主要矿相组成相近;随着m(MgO)/m(Al_2O_3)的增大,磁铁矿(Fe_3O_4)、硅酸盐(Ca_2SiO_4)、铁酸一钙(CaO·Fe_2O_3)等矿相含量有所升高;同时铁酸钙中固溶Al减少,铁酸钙形态由板片状向针状转变,并且产生富Mg的复合铁酸钙(SFCAM)。     

AlON/TiAlON_D/TiAlON_M/Cu光谱选择性吸收涂层高温真空稳定性研究

利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、透射电镜(TEM)和俄歇电子能谱仪(AES)研究了AlON/TiAlON_D/TiAlON_M/Cu选择性吸收涂层高温真空条件下显微形貌、结构与化学成分的变化。结果表明,退火前后选择性吸收涂层的多层膜结构和微观形貌保持稳定。制备态涂层的AlON层和TiAlON_D层为非晶结构,TiAlON_M层由非晶基体和分散的晶粒组成。550℃高温真空退火24 h后,TiAlON_M层发生晶化,晶粒长大。退火过程中,O元素从AlON层扩散至TiAlON双吸收层,而N元素从TiAlON双吸收层扩散至AlON层,同时膜层界面区域变宽。高温真空处理后涂层的吸收率略有降低,而发射率保持不变。晶化导致TiAlON_M层吸光性能下降,以及N和O元素扩散导致最优化结构被破坏是涂层吸收率衰减的主要原因。涂层在真空下热稳定激活能为189.5 k J·mol~(-1),表明涂层具有较好的热稳定性。     

Osteoclastogenesis inhibitory factor (OCIF)/OPG

A novel cytokine termed osteoclastogenesis inhibitory factor (OCIF) was purified to homogeneity from conditioned medium of human embryonic lung fibroblasts. OCIF is a heparin-binding basic glycoprotein with Mr of 60 kDa for a monomer and 120 kDa for a homodimer. OCIF specifically inhibits osteoclastogenesis in vitro and increases bone mineral density and bone volume in normal rats. The cloning of OCIF cDNA revealed that OCIF is a soluble member of the tumor necrosis factor receptor (TNFR) superfamily consisting of four cystein-rich domains, two death domain homologous regions (DDHs), and C-terminal basic domain. Mutational analysis of OCIF revealed that N-terminal portion of OCIF consisting of four cystein-rich domains is sufficient to inhibit osteoclastogenesis. OCIF inhibits osteoclastogenesis by binding to the sites expressed on osteoblastic cells and interrupting cell-to-cell signaling between osteoblastic cells and osteoclast progenitors.     

Parathyroid hormone-related peptide (PTHrP) and parathyroid hormone (PTH)/PTHrP receptor

Parathyroid hormone-related peptide (PTHrP) has been identified as the factor responsible for the humoral hypercalcemia of malignancy (HHM). Since the cloning of the cDNA, it has become clear that PTHrP is a prohormone that is posttranslationally cleaved to yield a complex family of peptides. Through its homology to parathyroid hormone (PTH) in the amino-terminus region of the protein, it is able to bind to and activate a common PTH/PTHrP receptor. PTHrP has been shown to be a normal product of many adult and fetal tissues, where it appears to act in an autocrine/paracrine fashion to regulate organogenesis. PTHrP and the PTH/PTHrP receptor seem to be co-expressed in many tissues, but their role in the various systems is uncertain. The use of transgenic and knock-out animal models has contributed to a better understanding of the physiological role of this peptide and its receptor. In this review, the structure of their genes, their expression pattern, and some of their major physiological functions are discussed. Attention is focused on their interaction in the regulation of cartilage and bone development.     

Sialyl Lewis(x)/E-selectin-mediated rolling in a cell-free system

Selections mediate transient adhesion of neutrophils to stimulated endothelial cells at sites of inflammation by binding counter-receptors that present carbohydrates such as sialyl Lewis(x). We have developed a cell-free adhesion assay using sialyl Lewis(x)-coated microspheres and E-selection-IgG chimera-coated substrates to investigate the premise that rolling primarily results from functional properties of selection-carbohydrate bonds, whereas cellular morphology and signaling act as secondary effects. Sialyl Lewis(x)-coated microspheres attach to and roll over E-selectin-IgG chimera-coated substrates between the physiological wall shear stresses of 0.7 and 2 dynes/cm2. Rolling velocities vary with time and depend on E-selectin-IgG chimera site density and wall shear stress. Our results show that sialyl Lewis(x) is a minimal functional recognition element required for rolling on E-selectin under flow.