细胞培养用温度敏感凝胶的合成与性能研究

用丙烯酸（ARc）对壳聚糖（CS）进行化学改性，合成反应中问体壳聚糖衍生物CS-ARc，进一步合成不同配比的CS-ARc与N-异丙基丙烯酰胺（NIPA）的共聚凝胶P（CS-AAc-NIPA），通过红外光谱和元素分析等表征了产物的结构和组成，并研究了P（CS—ARc-NIPA）凝胶在水中和细胞培养基中的溶胀性能．结果表明共聚凝胶在水中和培养基中均显示较好的温度敏感性．对P（CS-ARc-NIPA）共聚凝胶进行细胞培养研究发现，其表面可成功种植成纤维细胞（L929），细胞贴附生长情况良好，表明材料具有很好的细胞相容性．当环境温度降低后，共聚凝胶发生疏水．亲水变化，导致其表面细胞自动脱附，从而避免了使用酶解法脱附细胞造成的细胞功能损伤．’     

γ-聚谷氨酸温敏凝胶的合成及其生物相容性研究

通过自由基共聚合方法成功制备了γ-聚谷氨酸温敏凝胶P(γ-PGA-co-NIPAAm),研究发现r=0.05、0.10和PNIPAAm凝胶分别在33.1,33.6和32.5℃处发生可逆的温度相转变行为。与PNIPAAm凝胶相比,共聚凝胶更利于L929的细胞粘附和增殖,表明引入聚谷氨酸利于L929细胞的生长。通过控制温度变化,细胞从凝胶表面自动脱附,其活性大于PNIPAAm凝胶表面自动脱附和从TCPS板上通过酶解法得到的细胞的生物活性。     

聚天冬氨酸/木质纤维素水凝胶对Pb(Ⅱ)的吸附及脱附性能

以聚天冬氨酸(PASP)与木质纤维素(LNC)水溶液聚合法制备出的聚天冬氨酸/木质纤维素水凝胶(PASP/LNC)为吸附剂,对Pb(Ⅱ)进行吸附及脱附实验,研究溶液的初始离子浓度、pH值、吸附时间和吸附温度对溶液中Pb(Ⅱ)吸附量的影响。结果表明,溶液中Pb(Ⅱ)初始离子浓度为0.04 mol/L,溶液pH值为5.5,吸附时间为120 min,吸附温度为30℃时,PASP/LNC水凝胶对Pb(Ⅱ)的吸附量达到最大为972.35 mg/g。吸附过程符合准二级动力学模型,吸附等温线符合Langmuir模型。采用X射线衍射分析、比表面积和平均孔径分析、扫描电镜、傅里叶变换红外光谱分析PASP/LNC水凝胶的结构和吸附机理。使用HNO_3对PASP/LNC进行脱附实验。结果表明,HNO_3浓度为0.04 mol/L,脱附温度为30℃,脱附时间达到60 min时,最大脱附量为928.36 mg/g。吸附/脱附循环实验表明,PASP/LNC水凝胶重复使用4次后吸附量仍较高,是一种可重复使用的高效吸附材料。     

D-萘普生温敏分子印迹凝胶的制备及吸附性能研究

采用热聚合方法,以D-萘普生(D-Npx)为模板分子,N-异丙基丙烯酰胺(NIPAAm)为功能单体,N,N’-亚甲基双丙烯酰胺(MBAA)和二甲基丙烯酸乙二醇酯(EGDMA)分别为交联剂,制备了一种温敏DNpx分子印迹凝胶(MIH),研究了凝胶的温敏性以及交联剂的种类和浓度对凝胶结构和分离性能等的影响。研究结果表明,随着MBAA含量的增加,MIH的平衡溶胀率降低,且MIH对D-Npx的吸附和脱附量先增加后逐渐减少;随EGDMA含量的增加,MIH对D-Npx的吸附和脱附量逐渐增大。MIH具有明显的温敏性,MBAA含量对凝胶的最低临界溶解温度(LCST)几乎没有影响,凝胶表现出较好的溶胀-退胀性,脱附率可达90%以上。     

甲烷与氪共吸附条件下脱附行为的实验研究

对甲烷(CH_4)与氪(Kr)共吸附条件下的脱附行为开展了实验研究。研究了脱附温度、升温速率和吹扫流量对CH_4和Kr脱附行为的影响。实验结果表明:CH_4和Kr具有相似的脱附行为,在不同脱附温度、升温速率和吹扫流量下,CH_4和Kr脱附曲线的峰形和峰位基本相同; CH_4和Kr脱附曲线的出峰时间随脱附温度、升温速率和瞬时吹扫流量的增加而缩短,而CH_4和Kr的脱附曲线随累积吹扫流量的变化趋势在不同瞬时吹扫流量下基本相同。     

聚酰亚胺渗透汽化膜的研究(Ⅲ)水蒸气小分子在PI膜中的传质行为

以2种二酐、2种二胺为单体,制备了4种不同结构的聚酰亚胺(PI)均质膜;用建立的动态吸附／脱附实验装置测定水蒸气在PI膜中的吸附／脱附行为;考察了不同结构的PI膜对水蒸气吸附／脱附的影响;计算了反常扩散指数;研究了温度对水蒸气在聚酰亚胺膜(PI)中扩散系数的影响．分析了扩散系数与温度和聚合物重复单元的摩尔自由体积之间的关系．研究结果表明:水蒸气小分子在PI膜中的扩散系数随着温度增加而增加,随着聚合物重复单元摩尔自由体积的增加,扩散系数也呈上升的趋势．     

聚天冬氨酸/木质纤维素水凝胶的制备及吸附性能

采用水溶液聚合法合成聚天冬氨酸（PASP）/木质纤维素（LNC）水凝胶;考察了预处理时间、预处理温度、KMnO₄浓度、戊二醛用量、PASP的用量、反应时间以及反应温度对PASP/LNC水凝胶吸附Pb2+、Cd2+性能的影响;运用Langmuir吸附等温线计算PASP/LNC水凝胶最大吸附量;使用HNO₃对PASP/LNC水凝胶进行脱附再生实验;采用SEM和FTIR对水凝胶的结构进行表征。吸附结果表明:预处理时间15 min,预处理温度50 ℃、KMnO₄浓度0.06 mol·L-1、戊二醛用量1.00 g、PASP用量11 g、反应时间3.5 h且反应温度70 ℃时,对Pb2+、Cd2+的平衡吸附容量分别为980.39 mg·g-1、813.01 mg·g-1。 吸附/脱附循环实验表明:循环吸附脱附4次后PASP/LNC水凝胶吸附量仍较高,PASP/LNC水凝胶是一种可循环利用的吸附剂。表征结果表明:PASP/LNC水凝胶的表面有大小不等的孔隙,PASP的—COOH与LNC的O—H发生缩聚反应,形成具有三维网络结构的水凝胶。      

啶虫脒在超高交联吸附树脂上的吸附及脱附性能研究

本文从动态和静态的角度研究了均苯四甲酸酐修饰的超高交联吸附树脂（PMAR）和1,2,4-苯三酸酐修饰的超高交联吸附树脂（TMAR）对啶虫脒的吸附和脱附行为。结果表明：两种树脂对啶虫眯的吸附和脱附效果都比较好,TMAR的静态吸附量为470．9mg·g^-1干树脂,饱和吸附量为562．7mg·g^-1干树脂;PMAR的静态吸附量为453．4mg·g^-1干树脂,饱和吸附量为559．1mg·g^-1干树脂。两种树脂都易于脱附,用2mol·L^-1 HCl：乙醇（体积比1：1）作脱附剂,温度323K,脱附剂体积为9．5BV（床体积）时,PMAR的脱附率为98．13％,TMAR的脱附率为99．83％。     

Poly(DMAEMA-co-VP)/Fe_3O_4纳米复合水凝胶的制备及性能

以甲基丙烯酸-N,N-二甲氨基乙酯(DMAEMA)、4-乙烯基吡啶(VP)为单体,N,N-亚甲基双丙烯酰胺(BIS)为交联剂,在Fe_3O_4纳米粒子分散液中原位共聚制备了具有温度、pH、磁场三重响应性的纳米复合水凝胶。对纳米复合水凝胶的溶胀性能、温敏性、pH敏感性、磁场响应性等性能进行了研究,进而考察了纳米复合水凝胶对重金属离子(Cu~(2+))的吸附脱附行为。结果表明,纳米复合水凝胶具有良好的温敏性、pH敏感性和磁场响应性,并且对重金属离子(Cu~(2+))有可逆的吸附-脱附作用。     

细孔球形硅胶脱附性能的研究

目的 为了获得细孔球形硅胶被完全脱附活化时对应的温度区间,以及硅胶脱附温度与脱附时间的关系,为硅胶脱附活化工艺参数的设定提供一定参考。方法 通过高低温湿热试验箱让细孔球形硅胶在一定温湿度下充分吸附水分,再利用电热鼓风干燥箱在特定温度下,对2层堆积状态下的细孔球形硅胶进行脱附性能实验,得到脱附性能曲线,并根据曲线进行分析。结果 获得了2层堆积状态下细孔球形硅胶完全脱附活化对应的温度区间,以及脱附温度与脱附时间的关系,进一步得出细孔球形硅胶的最佳脱附活化温度区间为120~130 ℃。结论 通过对实验获取的细孔球形硅胶脱附曲线进行脱附性能分析,为细孔球形硅胶脱附活化工艺参数提供了一定的参考价值。     

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.     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Synthesis of Alumina-Zirconia Nanocomposites by Solgel Process

Al₂O₃-ZrO₂ nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.