乙基纤维素基聚MMA-BA复合高吸油树脂的制备及性能

以废弃棉织物所制备的乙基纤维素(EC)为基体,甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA)为接枝单体,过氧化苯甲酰(BPO)为引发剂,N,N′-亚甲基双丙烯酰胺(MBA)为交联剂进行接枝共聚制备了一种新型复合高吸油树脂[EC-g-P(MMA-co-BA)]。通过FT-IR、SEM对EC-g-P(MMA-co-BA)进行了表征,并对制备条件、吸油性能和动力学进行了探讨和分析。结果表明,当m(BA)∶m(MMA)=1∶1,ω(BPO)=0.3%,ω(MBA)=0.01%,ω(EC)=0.83%时所制备的树脂吸油性能最好。准二级动力学模型可以较为完整的描述该树脂的吸油过程,平衡时间大约为1.5h,其对4种油性物质的吸油速率大小依次为:甲苯邻二甲苯二氯甲烷三氯甲烷。     

镁铝双金属氧化物复合丙烯酸酯系吸油树脂的合成及吸附性能研究

以硝酸镁、硝酸铝和尿素为原料,并加入十二烷基磺酸钠制备了疏水性镁铝氧化物。以丙烯酸丁酯(BA)、甲基丙烯酸丁酯(BMA)和苯乙烯(St)为单体,聚乙烯醇(PVA)为分散剂,乙酸乙酯为致孔剂,过氧化苯甲酰(BPO)为引发剂,N,N′-亚甲基双丙烯酰胺(MBA)为交联剂,加入一定量疏水性镁铝氧化物,合成镁铝双金属氧化物复合丙烯酸酯系吸油树脂,并对该复合树脂的吸油性能进行了性能测试。结果表明,复合树脂对四氯化碳、三氯甲烷和甲苯的最高吸附倍率分别为42.89、36.29、26.85g/g。对复合树脂吸附四氯化碳的动力学模型拟合结果表明,复合树脂吸油符合准一级动力学模型。复合树脂的热重分析结果表明,复合树脂比原树脂的热稳定性有一定提高。     

速吸型吸油树脂的制备及性能研究

以甲基丙烯酸十二酯( LMA)、苯乙烯( St)和丙烯酸丁酯( BA)为共聚单体,制备速吸型吸油树脂。研究了单体配比等因素对树脂吸油率和吸油速率的影响。结果表明:1、成功制备了三元吸油树脂;2、当St的用量为40%( w),m( BA)∶m( LMA)=1∶2时,制备的三元吸油树脂对3#喷气燃料和甲苯的最大饱和吸油率分别为8.25 g/g、12.77 g/g。     

橡胶基丙烯酸酯系高吸油树脂的制备及性能

以丁苯橡胶(SBR)为基体,甲基丙烯酸十八酯(SMA)和乙酸乙烯酯(VAc)为聚合单体,过氧化苯甲酰(BPO)为引发剂,二乙烯基苯(DVB)为交联剂,在甲苯溶液中通过溶液聚合两步法得到新型改性高吸油树脂(R-OAR)。分别考察了单体配比、SBR、引发剂和交联剂用量作为单一影响因素对油品吸油平衡值进行了探讨,并结合傅里叶变换红外光谱(FT-IR)、热重分析(TGA)和扫描电子显微镜(SEM)对其进行表征。FT-IR表明,SMA、VAc成功接枝到SBR上,共聚形成了R-OAR;TGA表明,R-OAR热稳定性较高吸油树脂(OAR)好,分解温度提高了约50℃;单体配比为1.5∶1,SBR用量为5 g,BPO1和BPO2用量分别为4%和0.6%,交联剂为2%时,吸油平衡值达到最大,对柴油、甲苯、苯、四氯化碳分别为10.1 g/g,19.74 g/g,23.18 g/g,30.49 g/g;SEM表明,树脂中存在有利于提高其吸油能力的类交织状结构和织状间隙。     

聚氯乙烯接枝丙烯酸丁酯型吸油树脂的合成与性能

以轻度脱氯化氯的聚氯乙烯(PVC)、丙烯酸丁酯(BA)、二乙烯基苯(DVB)N原料,采用悬浮溶胀接枝共聚的方法合成一种新型高吸油性树脂。研究了BA含量、DVB用量、过氧化苯甲酰(BPO)用量等因素对其吸油性能的影响。该树脂对含氯的有机溶剂具有较高的吸附性．最高可吸三氯甲烷38g／g,氯苯31g／g。其对甲苯等其它有机溶剂的吸附性能与烷基丙烯酸酯型低交联吸油树脂的吸油性能相当。     

新型多组分聚丙烯酸酯类高吸油树脂微球的合成及性能研究

聚丙烯酸酯类吸油树脂因具有良好的吸油性、保油性而备受关注，目前研究大多集中在块材或粉末上，对微球状树脂的研究较少。微球因其加工更加方便、吸油倍率更高而备受关注。采用悬浮聚合法，通过调节软硬单体比例，维持反应体系稳定性，制备了分散性好的吸油树脂微球。以甲基丙烯酸十八烷基酯(SMA)、丙烯酸丁酯(BA)和苯乙烯(ST)为单体，二乙烯苯(DVB)为交联剂，偶氮二异丁腈(AIBN)为引发剂，环己烷(CYH)为致孔剂，合成P(SMA-co-BA-co-ST)高吸油树脂微球。采用红外光谱(FT-IR)、扫描电镜(SEM)、光学显微镜(OM)、热重分析(TG)等手段对树脂微球进行表征。结果表明：所得树脂微球分散性好、粒径均匀，比表面积大。系统分析了各因素对树脂吸油性能的影响，确定最佳反应条件：m[SMA∶BA]=3∶1、ω(ST)=25%、ω(DVB)=0.2%、ω(AIBN)=1.25%、ω(PVA)=1.25%、ω(CYH)=20%,对CCl₄、CHCl₃、CH₂Cl₂的饱和吸油倍率分别为33.50g/g、3...     

高吸油树脂的合成及回用研究

以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)及丙烯酸异辛酯(EHA)为共聚单体,二甲基丙烯酸乙醇酯( EGDMA)为交联剂,过氧化苯甲酰(BPO)为引发剂,明胶为分散剂,活性磷酸钙(ATCP)为助分散剂,采用悬浮聚合法在3L四口烧瓶中合成了三元共聚高吸油树脂.讨论了吸油时间、单体配比、交联剂用量及引发剂用量对树脂吸油...     

丙烯酸丁酯-苯乙烯共聚乳液型吸油树脂的合成及性能研究

以丙烯酸丁酯(BA)和苯乙烯(St)为单体,二乙烯基苯(DVB)为化学交联剂,采用乳液合成法制备吸油树脂.通过正交实验得到最佳合成配方,即BA∶ St=2∶1,w(二乙烯苯)=2％,w(过硫酸钾)=1％,w(丁苯橡胶)=O％,二甲苯的吸收率达到8.73g/g.同时探索了单体配比、DVB用量、油品种类对树脂吸油性能的影响...     

喷雾干燥法制备微米-纳米复合结构高吸油树脂中空微球

以苯乙烯和甲基丙烯酸十八酯为单体、甲基丙烯酸双环戊二烯酯为交联剂,采用喷雾干燥法制备了高吸油树脂中空微球.表征了高吸油树脂微球的微观形貌,考察了交联剂用量对树脂吸油性能的影响,同时与采用悬浮聚合法制备的树脂的吸油及疏水性能进行了对比.结果发现,采用喷雾干燥法制备的微球是由许多纳米粒子聚集而成的中空微米级微球;随着交联剂用量的增加,树脂吸油量呈先增加后减少的趋势,到达饱和吸油率所需时间减少;交联剂用量为3%(质量分数)的树脂吸油性能达到最好,对甲苯、三氯甲烷的饱和吸油率分别为20.78及28.32g/g,4h内对甲苯的吸收基本饱和;而采用悬浮聚合所制备的高吸油树脂,对甲苯和三氯甲烷的饱和吸油率分别为11.26、24.18g/g,12h吸油达到饱和;喷雾干燥及悬浮聚合制备的树脂与水的接触角分别为111.14与85.39°,表面能分别为38.10与42.85mJ/m2,采用喷雾干燥制备的高吸油树脂中空微球表现出较好的疏水性.     

聚甲基丙烯酸十二酯的合成及吸油性能

以甲基丙烯酸十二酯(LMA)为单体,采用悬浮聚合法合成了聚甲基丙烯酸十二酯(PLMA),研究了该树脂对柴油、汽油、甲苯和四氯化碳的吸油性能。结果表明,树脂的吸油率随着时间的延长不断增大,最后达到最大吸油率Qmax,CCl4的Qmax最大,为14.596 g/g,达到Qmax的时间约为110 min;柴油的的Qmax最小,为4.174 g/g,而吸油速率则随着时间的延长呈现出不断降低的趋势。树脂对CCl4、甲苯和汽油的保油率不到90%,对柴油的保油率达到90%以上。树脂的缓释保油率与油品的种类关系较大,树脂对甲苯和四氯化碳的缓释能力较大。     

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.