PDMS/PVDF复合膜渗透汽化分离乙酸/水体系的性能研究

制备了聚二甲基硅氧烷/聚偏氟乙烯(PDMS/PVDF)渗透汽化复合膜,用于分离乙酸/水体系。研究了料液中乙酸浓度、料液温度、料液流速对复合膜分离性能的影响,比较了不同孔径PVDF支撑层的PDMS/PVDF复合膜的分离性能。结果表明:料液浓度增大、温度升高、流速加快有利于复合膜的传质,使渗透通量增加,但分离因子却表现出不同的变化趋势。渗透通量的大小按复合膜支撑层孔径的排列顺序为0.2μm0.45μm0.1μm1.0μm2.0μm,分离因子则为0.1μm2.0μm0.2μm0.45μm1.0μm,说明支撑层的结构对复合膜的分离性能具有重要的影响。     

MoS_2/Ti复合膜的摩擦磨损研究

采用直流磁控溅射方法在SKD-11钢的表面沉积一层MoS2/Ti复合膜,选择沉积厚度为1μm和2μm的复合膜进行摩擦磨损实验,结果表明,MoS2/Ti复合膜为纳米复合膜,能大大降低钢表面的摩擦系数,改善钢的摩擦性能。适当增加膜的厚度,有利于提高钢的抗磨损性能。     

PVA/PVAm改性涤纶滤布复合膜的制备及其抗污染性能

利用聚乙烯醇(PVA)和聚乙烯胺(PVAm)的混合溶液,经刮膜、干燥和交联固定化处理,改性廉价涤纶滤布制备复合膜.亲水性PVA的羟基和PVAm的氨基被用来提高复合膜的亲水性和抗污染能力.考察了改性涤纶制备复合膜过程中PVA/PVAm共混比例、交联时间、交联剂用量、涂膜厚度以及涂膜次数对复合膜抗污染性能和渗透通量的影响.结果表明:当m(PVA)∶m(PVAm)=1∶1、交联时间为45min、交联剂质量分数为0.2%、涂膜厚度为100μm且涂膜交联2次制备的复合膜的抗污染性能最好.     

YSZ-Al2O3多孔复合膜的制备和表征

制备了氧化钇稳定的氧化锆(YSZ)膜层与氧化铝支撑体之间组分递变的YSZ-Al2O3复合膜层.为提高分离膜层的性能,考虑了组分递变及膜层厚度的控制.结果表明,复合膜层的热膨胀系数和烧结收缩率随着YSZ组分的增加而增加;烧结收缩率是选择复合膜层组分时应该考虑的主要因素.YSZ体积分数分别为20%和80%的YSZ Al2O3双层多孔复合膜,其可几孔径分别为0.72μm和0.36μm.该复合膜既是性能优良的微滤膜,也是制备氧化锆超滤膜和纳滤膜的良好支撑体.     

不同原料NCC对NCC/PVA复合膜性能的影响

分别以微晶纤维素、脱脂棉和漂白芦苇浆为原料,硫酸水解法制备纳米纤维素(NCC),与聚乙烯醇(PVA)简单共混流延成膜法制备NCC/PVA复合膜.m(NCC)/m总为7％时制备NCC/PVA复合膜,红外光谱分析结果表明复合膜中PVA分子链和NCC分子链间存在能提高两者相容性的氢键缔合作用力;热重分析结果表明复合膜的热稳定性与NCC热稳定性基本一致.扫描电子显微镜分析结果表明m(NCC)/m总为0.5％时制备NCC/PVA复合膜的表面和断面较为规整.3种原料中漂白芦苇浆NCC长径比最高(约为25),且m(NCC)/m总为0.5％时制备NCC/PVA复合膜拉伸强度最大,较PVA膜拉伸强度提高40.8％.3种原料NCC分别制备的3种NCC/PVA复合膜断裂伸长率,均较PVA膜断裂伸长率降低.随着m(NCC)/m总的增加,NCC/PVA复合膜透光率较PVA膜透光率降低;3种原料中微晶纤维素NCC/PVA复合膜透光率较PVA膜透光率降低最小.     

低成本超薄复合膜用于不同溶液体系钒电池的性能研究

采用廉价的聚烯烃微孔膜作为支撑体,全氟磺酸离子交换树脂作为复合相,设计并制备了成本低、机械强度高、性能优异的超薄液流电池复合膜.研究了在H_2SO_4和HCl不同体系下复合膜的氢离子传导、钒离子渗透、电池性能.结果表明,25μm复合膜具有较高的机械强度和较低的溶胀率;在混酸钒溶液体系(1.5 mol/L VOSO_4+1.5 mol/LH_2SO_4+2.5 mol/L HCl)的电池性能优异,100 mA/cm~2下能量效率(EE)为80%.同时,复合膜成本较低(40～60元/m~2),具有应用前景.     

烧结NdFeB永磁体表面Ni-P／TiO2复合膜的耐腐蚀性能

采用化学镀镍和溶胶-凝胶成膜技术,在烧结NdFeB永磁体表面形成了Ni-P/TiO2复合膜,XRD分析结果表明,复合膜为非晶态结构.Ni-P/TiO2复合膜在0.5 mol/L H2SO4溶液中的Jcorr、Rp为2.38μA/cm2和12.5 kΩ·cm2,分别为Ni-P镀层的1/3和1.6倍;复合膜在0.5 mol/L NaCl溶液中的Jcorr、Rp为0.22μA/cm2和120 kΩ·cm2,分别为Ni-P镀层的1/7和2.0倍.Ni-P/TiO2复合膜耐盐雾时间超过Ni-P镀层2.5倍.所制备的Ni-P/TiO2复合膜较Ni-P镀层有更佳的耐腐蚀性能.     

HTBN/PAN复合膜分离正庚烷/乙硫醚/正丁硫醇混合物的渗透汽化研究

制备了一系列HTBN/PAN复合膜,用于渗透汽化脱除正庚烷/乙硫醚/正丁硫醇混合物体系中的乙硫醚和正丁硫醇,此复合膜优先脱除乙硫醚和正丁硫醇.通过扫描电子显微镜(SEM)对复合膜的表面和断面进行表征.考察了复合膜在正庚烷和正庚烷/乙硫醚/正丁硫醇混合物体系中的溶胀性以及复合膜在长时间操作下的稳定性,研究了膜液浓度对膜结构和膜分离性能的影响以及操作温度对膜分离性能的影响.结果表明:交联的HTBN在PAN多孔膜表面形成均匀致密的分离层;膜在正庚烷及正庚烷/乙硫醚/正丁硫醇混合物体系中的溶胀度均小于5%;操作温度对于膜的富硫因子影响不大,而渗透通量则随着温度的升高而增大;对于正庚烷/乙硫醚/正丁硫醇混合物分离体系(含硫量为160μg/g),在80℃,50 h长时间操作下,HTBN/PAN复合膜的渗透通量为0.23 kg/(m2.h),富硫因子为2.85.     

以核孔膜为基底疏/亲水复合膜的制备及其DCMD性能研究

创新性地将核孔膜作为基膜,使用聚偏氟乙烯(PVDF)为膜材料,N,N-二甲基乙酰胺(DMAc)为溶剂,采用非溶剂致相分离法制备了PVDF/PET核孔膜复合疏水/亲水膜,并对复合膜的微观结构、机械性能、亲疏水性、孔隙结构进行深入表征,研究了添加剂含量和核孔膜孔径对膜微观形态和性能的影响.结果表明,提高LiCl添加剂含量使得铸膜液的黏度增大,膜指状孔结构变小且海绵状结构变紧密,PVDF/PET核孔复合膜的平均剥离力从4.48 N下降为1.19 N,孔径从0.132 7μm减少到0.080 4μm,孔隙率从44.65%减少至37.60%;核孔膜孔径增大导致复合膜的机械强度下降.直接接触式膜蒸馏(DCMD)分离性能测试表明,PVDF/PET核孔复合膜通量比相同厚度单层PVDF疏水膜通量提升约30%;可稳定运行超过39 h.     

矿化柞蚕丝胶膜表面粗糙度的调控及其对骨髓间充质干细胞生长行为的影响

生物材料表面的粗糙度是影响细胞行为的重要因素之一。为了调控丝蛋白生物材料表面的粗糙度,并评价材料表面粗糙度对细胞生长行为的影响,首先,通过湿化学共沉淀法,以柞蚕丝胶(AS)溶液为模板,诱导了羟基磷灰石(HAp)晶体成核,进而调控了AS膜表面的粗糙度。然后,采用SEM、粗糙仪、FTIR及EDX等对HAp/AS复合膜表面形貌、粗糙度及成分进行了表征。最后,通过SEM和CellTiter 96?AQueous单溶液细胞增殖检测试剂盒(MTS)检测了骨髓间充质干细胞(BMSCs)在HAp/AS复合膜表面的形貌及增殖率。结果表明:纯AS膜的表面粗糙度为0.15μm,矿化1、8及24h后,表面粗糙度分别为0.38、0.46和1.20μm;矿化24h后,在HAp/AS复合膜表面可观察到直径为30~80nm的球状复合物,生成的矿化物为HAp;HAp/AS复合膜具有良好的细胞相容性,表面粗糙度为1.20μm的复合膜能够显著促进BMSCs的增殖,粗糙度对BMSCs在HAp/AS复合膜表面的粘附和形貌有着重要的影响。因此,可通过矿化的方法在生物大分子表面诱导HAp晶体的成核与生长,从而调控材料的表面粗糙度,研究材料界面上的细胞行为。     

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.     

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.     

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.     

中国质量(北京)大会(英文)

正Themed on"quality,innovation,development",the first China Quality Conference(Beijing)was held in the Great Hall of the People on September 15.Chinese Premier Li Keqiang delivered an important speech at the conference.State Councilor Yang Jing and Wang Yong attended the conference with over 600 domestic and international representatives from foreign,regional and international quality organizations     

National Working Meeting on Land and Resources Standardization

正The National Working Meeting on Land and Resources Standardization was held in Beijing on July 15,2014.Wang Min,the Deputy-Minister of the Ministry of Land and Resources,and Yin Minghan,the Chief-Engineer of SAC addressed the meeting.Representatives from relevant competent departments and technical committees were present.The meeting aims to summarize work,discuss existing problems and make clear working thoughts,promoting standardization work of land and resources to a new level.Wang Min pointed out that the standardization work of land and resources should be centered on the basic principles of"protecting land and resources dutifully,intensively and economically utilizing land and resources,and making all-out efforts to safeguard the public’s rights and interests",highlighted the