YAG:Ce3+微粉的制备及光谱性能

本文以高分子网络凝胶法制备Ｙ３Ａｌ６Ｏ１２（ＹＡＧ）Ｃｅ＾３＋微粉，并测试其光谱特性。与普通的共沉淀法合成的（ＹＡＧ）：Ｃｅ＾３＋相比，高分子网络凝胶法于比较低的温度下（９９０℃）获得ＹＡＧ物相，合成的（ＹＡＧ）：Ｃｅ＾３＋微粉光谱谱峰存在明显的蓝移现象。     

高分子网络凝胶法制备纳米YAG粉体

以Al（NO3）3硝酸铝和Y（N32）3硝酸钇为原料，采用高分子网络凝胶法制备纳米YAG粉体，对网络凝胶机理和胶体的煅烧过程进行了研究。研究表明干凝胶在900℃煅烧即可全部转变为YAG纯相，没有YAM、YAP等中间相生成。所制备的粉体粒度尺寸大小为20nm左右，颗粒呈球形，有轻微团聚。     

高能球磨与反应烧结合成YAG：Ce^3＋荧光粉的研究

采用高能球磨和反应烧结相结合的方法在1300℃、碳还原气氛下合成了YAG：Ce^3＋荧光粉，通过X射线衍射分析（XRD）、场发射扫描电子显微镜图谱（FESEM）、荧光光谱（Ex，Em）研究了反应时间、Ce^3＋的掺杂量对荧光粉性能的影响。研究结果表明，当反应时间为6h时获得的产物为单一的YAG相，颗粒分布均匀且接近球形；当掺杂Ce抖的摩尔分数x=0．06时，荧光粉的相对发射强度最大。     

溶胶-凝胶法制备YAG的若干影响因素

采用溶胶-凝胶（sol-gel）法，以柠檬酸为络合剂，利用硝酸盐制备出了YAG粉体。实验合成了Y2O3占35％-40％（摩尔分数）的YAG粉体，利用热重，差热分析（TG／DTG）、X射线衍射（XRD）、傅立叶红外光谱（FT-IR）、透射电镜（TEM）等手段对YAG前驱体及煅烧物粉体进行了表征。结果表明，通过提高对前驱体的煅烧温度，延长煅烧时间等方法，在900℃下煅烧不同配比的YAG前驱体，均制得了纯相的YAG粉体，表明在以往YAG的合成中易出现的中间相，并不只是组分的不均匀性造成的，还与煅烧温度和煅烧时间有关。     

YAG：Ce，Tb粉体的共沉淀法制备与发光性能

以NH4HC03溶液为沉淀剂，采用共沉淀法制备了前驱体，在氩气气氛中经1200℃煅烧2h合成了Y2.91-xCe0.06TbxAl5O12（YAG：Ce，Tb）粉体。利用X射线衍射仪、透射电子显微镜、荧光光谱仪对样品的结构、形貌及发光性能进行了表征。所得粉体为体心立方相YAG：Ce，Tb。粉体颗粒团聚成珊瑚虫形。YAG...     

(Ceo.67Tb0.33)MgAl11O19荧光粉的溶胶-凝胶法合成及发光性能

采用溶胶-凝胶法合成（Ce0.67Tb0.33）MgAl11O19绿色荧光粉。利用TG-DTA和XRD等实验技术，研究了荧光粉的形成过程，找出了最佳合成条件，并对其粉体形貌和发光性能进行研究。结果表明，用溶胶、凝胶法合成的（Ce0.47Tb0.33）MgAl11O19是一种性能优良的荧光粉。     

掺杂对白光LED用YAG：Ce荧光粉发光性能的研究

采用高温固相法合成了YAG：Ce荧光粉，研究了掺杂元素对YAG荧光粉发光性能的影响。研究表明：YAG：Ce荧光粉亮度随着Ce含量增加先上升后下降。Sm的掺杂对荧光粉发射光谱峰位无影响，而发光亮度却明显下降。随着Gd掺入量的提高，YAG荧光粉的发射光谱发生红移，发光亮度有所下降。YAG：Ce荧光粉的发射光谱，随着Lu掺入量的提高，发射光谱发生蓝移，发光亮度略有下降。在YAG：Ce中掺入Pr，发射光谱在610nm处出现尖锐的红峰，但随着Pr掺入量的增加，亮度明显下降。     

新型互穿网络超大孔水凝胶的制备、性能及表征

以丙烯酸、丙烯酰胺为基体，以乙烯基吡咯烷酮为预聚体，利用新型两步聚合法和发泡技术，制备了聚（丙烯酸．丙烯酰胺），聚乙烯基吡咯烷酮互穿网络超大孔水凝胶．采用差示扫描量热法（DSC）、红外光谱（FT-IR）和扫描电镜（SEM）等分析技术对所得水凝胶进行了表征，并研究了水凝胶的溶胀行为和凝胶强度．实验结果表明：该水凝胶具有相互连通的孔结构，溶胀行为在几分钟内即可完成；以新型两步法制备的互穿网络结构（IPN），大大提高了超大孔水凝胶的强度，新型两步法是制备IPN的有效方法之一．     

光学基质粉体YAG及荧光粉体Ce:YAG的制备与表征

采用共沉淀法制备出尺寸分布均匀、分散性良好的立方相钇铝石榴石(YAG)与Ce:YAG纳米粉体.考察了煅烧温度和时间对粉体物相和颗粒大小的影响及Ce~(3+)的掺杂量对Ce:YAG粉体的荧光光谱的影响.借助IR、XRD、BET、SEM和荧光分析仪等测试手段对前驱体、YAG及Ce:YAG纳米粉体进行了表征与分析.结果表明:共沉淀前驱体经900℃煅烧2h后可得到纯立方相的YAG(Ce:YAG)纳米粉体;所得Ce:YAG粉体具有较好的荧光特性且Ce~(3+)的掺杂量增加会造成其荧光光谱红移.     

[Li]／[Nb]比变化对Ce：Mn：LiNbO3晶体光折变性能的影响：

采用提拉法生长4种不同[Li]／[Nb]比（0．94，1．05，1．20，1．38）的Ce（0．1％（质量分数））：Mn（0．05％（质量分数））：LiNb03晶体和掺镁量为5％（摩尔分数）的Mg：Ce（0．1％）：Mn（0．015％）：LiNbO3晶体。测试晶体红外光谱，[Li]／[Nb]为1．2和1．38的Ce：Mn：LiNb03晶体OH吸收峰移到3466cm^-1，这是化学计量比的标志吸收峰。Mg（5％（摩尔分数））Ce：Mn：LiNbO3晶体OH吸收峰移到3535cm^-1，这是Mg^2＋达到阈值浓度的标志吸收峰,以锂空位模型解释OH-吸收峰移动机理。采用光斑畸变法测试晶体抗光损伤能力，采用二波耦合光路测试晶体的指数增益系数、响应时间、计算载流子浓度。随着[Li]／[Nb]比增加，这些数据指标增加。[Li]／[Nb]为1．38，Ce：Mn：LiNbO3晶体是化学计量比，它的指数增益系数比Ce：Mn：LiNbO3晶体提高1倍，响应速度和抗光损伤能力提高1个数量级以上，是性能最为优良的光折变晶体材料之一。     

Effect of Permeable Crystalline Material on Steel Reinforcement Corrosion of Concrete

Permeable crystalline materialcan permeate into pores and cracks of concrete and catalyze the reaction between Ca(OH) 2and unhydrated cement to generate a great quantity needle non-soluble crystals, which can stop up the pores and cracks of concrete, and increase the impermeability of concrete. This paper reported the results of a study conducted to evaluate steel reinforcement corrosion of concrete specimens uncoated and coated with permeable crystalline material as well as mixed with the permeable crystalline material. The properties evaluated for corrosion test were water impermeability, water absorption, compressive strength and potential. The results of water impermeability, water absorption, compressive strength clearly showed that the permeable crystalline material could prohibit water, any soluble salts and moisture from penetrating the concrete to cause corrosion, leaking, and other problems, and it did increase the compressive strength, which was favorable for protection of corrosion of reinforcing steel. Moreover, it was concluded from the potential-time curve that the steel reinforcement of uncoated specimen was in the state of activation whereas that of other specimens coated and mixed with the permeable crystalline material was in the state of inactivation. Above all, it was indicated that the permeable crystalline materialis very effective to protect the steel reinforcement of concrete from corrosion.     

The Research and Application About "Dry Peeling Off" Technology for Airplane Surface Paint Layer

In this paper, the principle of spurting take off lacquer were introduced; and with orthogonal method the unsaturate polyester was prepared ;it was easy to peel airplane paint layer off with this material and equipment.     

Quality Study of Honeycomb Core Shaping Without Wax Stabilization

Sandwich panels utilizing honeycomb cores result in lightweight, high-strength units that are very rigid. Indeed, they give honeycomb panels the best strength-to-weight ratio of any construction type available. Conventionally, the wax is poured into the cell of the core to strengthen the structure and prevent the core from being crushed during milling. Much time and labor is required to wax, mill, and clean the cores. In this study, the process of pouring wax into the core was skipped. In other words, the cutter directly milled the core. Experiments showed that the compressive strength of the core produced without wax stabilization was only 3% lower than that of cores produced using the traditional method. In addition, the drum peel strengths of cores produced without wax stabilization were 38.4% higher than cores produced using the traditional method, in which residual wax seriously polluted the adhesive. It was also found that eliminating the wax process can reduce costs.     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

In-process thermal treatment of polylactic acid in fused deposition modelling

Polylactic acid (PLA) is one of the most widely used open source fused filament fabrication materials due to its ease of extrusion, biodegradability, and mechanical strength. The mechanical strength of PLA largely depends on the proper growth of its semi-crystalline structure, which can be severely impaired by a low rate of crystallization, particularly in open source printers. This can be further aggravated by the non-uniform thermal distribution of heat that causes improper curing among the extruded beads of the printing material. As a result, PLA printed on open source printers does not achieve the best mechanical properties. This research, for the first time, proposes an additive-free solution implemented through a detailed set of experimentation to improve the curing rate through in-process temperature variations to cure the joints among the beads. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy is used to confirm the improvements in the bead joints. This work is conducted in two phases of experiments. In the first phase, a full factorial ANOVA is used to investigate various process parameters and the important variables are used in the second phase to print test specimens in four different sets.     

Investigation of the Corrosion Behaviors of HVOF-Sprayed Carbide Cernet Coatings in Molten Al-Zn-Si Alloy Bath

In continuous hot-dip galvanization process the corrosion and chemical stability of the sink roll in the galvanizing bath are important problem which effects on the quality and productivity. In order to protect the sink roll the carbide cermet and/or ceramic coatings were deposited on the surface of the sink roll. The WC-, Cr3 C2-cermet coatings were deposited by high velocity oxygen fuel (HVOF) spray, respectively. The coating samples were immersed in molten Zn-alloy containing 50 wt % aluminum at 833 K for 24 hr and 144 hr, respectively. The inter-diffusion and inter-reaction of Zn, Al and elements in coating and corrosion behaviors of these coatings were investigated by XRD, SEM and EPMA etc. The corrosion mechanisms of the carbide cermet coatings and ceramic coatings in molten High Al-Zn-alloy were approached.     

Fundamental study of adhesion of ice to cooling solid surface (Discussion on influence of copper oxide layer on ice adhesion force)

In many situations, ice often adheres to a cooling solid surface, frequently causing serious accidents. It is critical to clarify the mechanism of ice adhesion to the cooling surface in order to prevent ice adhesion. In a past study, the shearing stresses of two kinds of test plates with a copper surface having the higher thermal conductivity were measured. The shearing stress corresponds to ice adhesion force. Both shearing stresses were significantly different; however, the cause remains unclear.Therefore, the present study focuses on an oxide layer as the main factor causing the difference of both shearing stresses; the influence of the oxide layer formed on shearing stress was discussed. And in the removal and reformation processes of the oxide layer, the time variation of the shearing stress was clarified. Moreover, the relationship between the state of the copper surface and the shearing stress was also clarified by surface analysis.     

＂Three Transformations＂ and Standardization

During his inspection in Henan Province in May, Chinese President Xi Jinping stressed to ＂push forward the transformation from China Speed to China Quality, from Made in China to Created in China, and from Chinese Products to Chinese Brand＂. The ＂Three Transformations＂ are the specific requirements and goal of China＇s national development in the context that market should play a decisive role in the allocation of resources.     

重塑标准推行格局 推动LED照明的普及（英文）

正When you are enjoying the green,energy-saving and healthy lighting of IKEA LED luminaire,you may not realize that most of IKEA’s LED bulbs are produced by the LED luminaire smart manufacturing system of Hangzhou Zhongwei Photoelectricity CO.,LTD(ZVISION).No longer enclosed in the laboratory,the product standards are brought into the factory workshop and even to the entire production process.Thus,the standards are promoted and applied in a favorable way by enterprises,benefitting consumers with high quality products.     

Chinese Experts Contribute to ISO＇s New Toy Standards

正The international standard,ISO 8124-6,Safety of toys–Part 6:Certain phthalate esters in toys and children’s products,was officially issued by ISO worldwide on August 15.It was the first time for Chinese experts to lead the ISO standard development in toys industry.The standard was drafted by a group of Chinese experts from SAC/TC for toys and relevant Chinese departments and finally completed by a dedicated international group of experts.ISO 8124-6 makes a substantive breakthrough in the aspects of the scope of toys,limitation of plasticizer types,control of test cost,accuracy of test,operation convenience,etc.,offering the operational guidance for toy manufactures and testing laboratories.