一种新型多功能附聚剂的制备

以丙烯酸丁酯（BA）、甲基丙烯酸和苯乙烯等为原料合成了一种新型多功能附聚剂。探讨了水油比、引发剂用量、不同乳化剂对附聚剂粒径、粘度和固含量的影响,并对附聚剂共聚物的红外谱图进行了分析,最终得到了附聚剂的最佳工艺配方。     

乳胶粒子用附聚剂的制备及应用

采用丙烯酸(AA)、丙烯酸丁酯(BA)混合单体通过乳液聚合方法合成附聚剂,用于聚丁二烯胶乳(PBL)的附聚.研究了附聚时间、附聚剂组成、附聚剂加入量、附聚剂的粒子尺寸等因素对聚丁二烯(PB)胶乳粒径大小的影响.结果表明:附聚时间为40～60 min时,附聚过程基本完成;当BA/AA质量比为80/20时,附聚效果最好;附聚剂在PBL中加入量占PBL总质量的8.3％时,附聚效果明显;PBL平均粒径由原来的96nm附聚到了240～260 nm,粒径得到了明显的增长,合成的附聚剂有良好的附聚效果.     

用高分子附聚法制备大粒径聚丁二烯胶乳

采用高分子胶乳附聚法对小粒径聚丁二烯胶乳（ＰＢＬ）进行附聚,制备大粒径ＰＢＬ。研究了合成附聚剂时的加料方式和不饱和酸用量、附聚剂用量、体系ｐＨ值、附聚温度及其他附聚工艺条件对附聚效果的影响,并对比了附聚前后ＰＢＬ的形态。结果表明,当在合成附聚剂的初期加入丙烯酸乙酯的质量分数为其总量的２０％ ～４０％、不饱和酸的质量分数为１０％以及附聚剂质量分数为１．５％、体系ｐＨ值为９～１０、附聚温度为４０℃和附聚时间为１ｈ时,附聚的效果最好。     

高分子附聚剂增大聚丁二烯胶乳粒径的研究

用丙烯酸正丁酯(BA)和甲基丙烯酸(MAA)合成了高分子附聚剂,并制备了大粒径聚丁二烯胶乳(PBL)。研究了PBL含量(在规定条件下烘干后剩余部分占总量的质量分数)、附聚剂用量和附聚剂中MAA含量对附聚效果的影响。结果表明：当PBL质量分数为30.0%、附聚剂质量分数为2.5%～3.0%、附聚剂中MAA质量分数为15.0%时,可制得粒径大于300 nm、粒径分布为单峰的稳定PBL。     

附聚法制备大粒径聚丙烯酸丁酯胶乳的研究

以非离子和阴离子表面活性剂为复配乳化剂,制备了丙烯酸丁酯/丙烯酸共聚胶乳,以其为附聚剂制备了大粒径的PBA胶乳,采用红外光谱仪、Zeta纳米粒度仪、Zeta电位仪和透射电镜表征了附聚剂的结构特征、附聚前后PBA胶乳粒子的粒径、电位和形态变化。结果表明:当附聚剂胶乳与PBA胶乳质量比为1/20~1/5时,可使PBA胶乳粒径尺寸扩增4倍以上,附聚后胶乳的表面电位值有所下降。     

高分子附聚法制备超大粒径聚丁二烯胶乳

以自制丙烯酸胶乳为高分子附聚剂,以粒径300nm聚丁二烯胶乳(PBL-0700)为起始胶乳,采用高分子附聚法制备了500～600nm超大粒径聚丁二烯胶乳(目标胶乳),考察了附聚剂加入量、放置时间、后稳定剂的加入、附聚温度等因素对目标胶乳粒径的影响,确定了高分子附聚法超大粒径聚丁二烯胶乳制备工艺。     

醋酸附聚制备大粒径PB胶乳影响因素的研究

以醋酸为化学附聚剂,对小粒径PB胶乳进行化学附聚,研究醋酸浓度、醋酸加入量、附聚温度、附聚时间对附聚效果的影响,评估醋酸附聚制备的大粒径PB胶乳性能。     

玉米加工蒸煮液等添加剂对炭黑粘着强度和电性能的影响

本文考察了玉米加工业蒸煮液（Nejayote，玉米饼加工业产生的废水，俗称黄浆水）及其它添加剂（水、木素磺酸钾、糠醇）对炭黑附聚体的粘着强度和电性能的影响。炭黑附聚体的热稳定性与木素磺酸钾、糠醇和该蒸煮液相似。蒸煮液和木素磺酸钾对炭黑附聚体的粘着强度的影响也相似，然而对电性能的影响不同。含蒸煮液的炭黑附聚体具有较低的导电率。水对炭黑附聚体粘着强度的影响不严重，但对其导电性却至关重要。蒸煮液是玉米加工业的一种无用的副产品，在炭黑造粒过程中可作为有潜力的促聚剂。     

改善重悬浮液流变性的研究

我国某大型胶磷矿的重介质分选试验,使用铁精矿作悬浮液的加重剂。为了改善悬浮液的流变性,提高选别指标。试验采用了一些措施,其中以加温,脱泥和添六聚偏磷酸钠较为有效。硅铁和磁铁矿配用也是一种可以选取的方法。     

高分子附聚法450nm聚丁二烯胶乳的制备研究

高分子附聚方法是一项独特的技术。特别是在制备超大粒径胶乳方面,可以在较短的时间内制备稳定的胶乳,从而改善产品质量,提高生产效率。作者对制备粒径450nm聚丁二烯胶乳的附聚工艺进行了深入研究,考察了附聚剂胶乳用量、附聚后静置时间、乳化剂用量和搅拌强度等附聚工艺对聚丁二烯胶乳粒径及稳定性的影响,确定了制备450nm聚丁二烯胶乳较为优化的附聚工艺,制备的聚丁二烯胶乳稳定,可用于高性能ABS的制备。     

尾矿的砷污染试验研究及治理措施

随着含砷矿床的开采,导致砷由地层深处转至地表,改变了它们迁移的地球化学条件,容易释放到周围环境中容易释放到周围环境中。文章以马鞍桥金矿为例,通过对马鞍桥金矿的尾矿进行淋滤试验和分级提取试验,来分析其迁移转化情况和对环境的影响。实验的结果表明:淋滤液中,砷含量在0.8～2.88μg·L-1之间,没有超过国家地表水标准,但是分级提取实验结果表明尾矿残渣中64.55%的砷为易迁移态,在尾矿长期堆放过程中,这些易迁移态的砷会转移到周围环境中,从而造成环境污染,并提出了相应的治理对策。     

Perception of gold materials by projecting a solid color on black materials

Gold gives a unique luxurious impression and therefore golden objects are often desired. Since gold is an expensive metal, due to its rarity, it is not feasible to produce objects made of gold at reasonable prices. In this study, we have developed a simple representation method that makes real objects appear to be made of gold using projection mapping technology. In recent years, this technology has been extensively explored, mainly in the field of entertainment. Most of these studies were focused on technologies where a target image was superimposed onto an object. Our method, unlike the conventional approach, does not project a target gold image but simply projects a solid color onto an object, thereby giving the perception that the object is made of gold. We have conducted two psychophysical experiments to substantiate our representation method, using stimuli having the same color. Our results indicate that objects were more easily perceived as golden objects when a solid color was projected onto black objects rather than white objects. Furthermore, a few samples were perceived as metals, even though they were actually paper or fabric. These results suggest that when superimposing a solid color onto an object, a change in material type is perceived along with the change of its color. Moreover, we analyzed the relationship between psychophysical evaluations on the perception of projected gold objects and the physical properties of the materials. The results show that the average and the standard deviation of reflectance generated by black objects can be considered factors that affect the perception of a gold‐like color. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 522–530, 2017     

Orthogonal Curvilinear Cake Filtration

Abstract

Conventional analysis of cake filtration considers cakes formed under one-dimensional rectilinear flow conditions. Other cake geometries are often encountered in practice, and more generalized equations are needed. An orthogonal curvilinear filter cake equation is derived here for an arbitrary orthogonal cake geometry. This equation is applied to rectangular, cylindrical, oblate-spheroidal, and elliptic-cylindrical geometry cakes through the coordinate scale factors. Experiments are run on Lucite cakes in rectangular and elliptic-cylindrical coordinates. The constitutive parameter, Λ, is determined from experiments in rectangular coordinates and is used to predict the performance of an elliptic-cylindrical cake. Comparison of the predicted results with the experimental results of the elliptic-cylindrical cake shows the consistency of the equation for different geometries. The filter assembly used in the experiments was designed to be pressurized without being submerged within a larger slurry agitation vessel. This allows ready access to the assembly walls for placement of probes for measuring local pressure and porosity in rectangular and elliptic-cylindrical geometries.     

粉煤灰对混凝土拌合物泵送性能的影响

介绍了粉煤灰对掺有M17塑化剂的混凝土拌合物泵送性能和混凝土强度的影响，通过扫描电镜对粉煤灰颗粒形貌进行了观察，初步探讨了粉煤灰的作用机理。试验说明在接有M17塑化剂的泵送混凝土中加入粉煤灰，可增加坍落度，降低泌水率，泵逆性能可得到改善。     

On Homogeneous Gold/Palladium Catalytic Systems

Two substrates containing an aryl iodide and an allenoate ester were prepared and the gold‐induced cycloisomerisation to vinylgold(I) species and their proto‐deauration as well as the intramolecular palladium‐catalysed cross‐coupling reactions were investigated. Switching to catalytic amounts of gold and palladium and stoichiometric amounts of silver did indeed furnish the product of a cycloisomerisation/intramolecular cross‐coupling. Control experiments revealed that silver cannot substitute for gold or palladium in these reactions, but a different palladium catalyst in a different oxidation state also afforded the cycloisomerisation/intramolecular cross‐coupling products in only slightly reduced yields. By ICP analysis the palladium was shown to contain gold only at the sub‐ppm level. This shows how carefully results obtained with such systems have to be interpreted. Then a series of allylic and benzylic o‐alkynylbenzoates were investigated in gold‐ and palladium‐catalysed reactions. For esters of benzyl alcohol and cinnamyl alcohol no palladium co‐catalyst was needed for the conversion. All reagents were thoroughly checked for palladium traces by ICP analysis in order to thoroughly exclude a gold/palladium co‐catalysis. Optimisation of the gold complex, counter ion and solvent showed that gold(I) isonitrile pre‐catalysts and silver triflate as activator in dioxane are suitable to convert a number of substrates with aryl, alkyl and even cyclopropyl substituents. Crossover experiments proved an intermolecular allyl transfer.     

纯胶卤化银乳剂化学增感的研究

本文中应用了国产纯胶制备卤化银乳剂并运用正交设计的方法确定了乳剂中化学增感剂用量的最佳配比。当选用金、硫、亚硫酸钠作为化学增感剂时,通过采用合适的工艺方法,在相同的曝光、显影条件下,胶片的感光度从原配方的S=16DIN增加到S=25DIN。另外,参照金、硫、亚硫酸钠的最佳配比,用氯化亚锡代替亚硫酸钠,感光度也达到了S=24.7DIN。由此可见,为了得到较佳的照相性能;可运用正交试验来研究化学增感剂之间的配比,其结果是令人满意的。     

含超细Au颗粒的乳酸氧化酶和葡萄糖氧化酶生物传感器

制备了小于10 nm的金颗粒，并利用其进行固定化葡萄糖氧化酶和乳酸氧化酶的研究. 实验发现，金纳米颗粒可以大幅度提高葡萄糖氧化酶电极和乳酸氧化酶电极的电流响应，响应电流从相应浓度的几十纳安增强到几千纳安. 探讨了金纳米颗粒在固定化酶中所起的作用.     

pH-triggered conduction of amine-functionalized single ZnO wire integrated on a customized nanogap electronic platform

The electrical conductance response of single ZnO microwire functionalized with amine-groups was tested upon an acid pH variation of a solution environment after integration on a customized gold electrode array chip. ZnO microwires were easily synthesized by hydrothermal route and chemically functionalized with aminopropyl groups. Single wires were deposited from the solution and then oriented through dielectrophoresis across eight nanogap gold electrodes on a platform single chip. Therefore, eight functionalized ZnO microwire-gold junctions were formed at the same time, and being integrated on an ad hoc electronic platform, they were ready for testing without any further treatment. Experimental and simulation studies confirmed the high pH-responsive behavior of the amine-modified ZnO-gold junctions, obtaining in a simple and reproducible way a ready-to-use device for pH detection in the acidic range. We also compared this performance to bare ZnO wires on the same electronic platform, showing the superiority in pH response of the amine-functionalized material.     

The Effects of Various Flotation Parameters on Gold Recovery by Coal-Oil Assisted Gold Flotation

The effects of different physical parameters such as pulp density, aeration conditions, and impeller speed on the performance of coal-oil assisted gold flotation were investigated in this study. The experiments were conducted using samples taken from an epithermal gold ore deposit. The results demonstrated that increasing the solid concentration in feed pulp slightly improves recovery of gold particles, but accompanied by significant decreases in concentrate grade. At low aeration conditions gold recovery was relatively low whereas at high aeration conditions the selectivity was poor. The use of higher level of agitation in the agglomerate re-formation stage brought about an increase in gold recovery; however, gold grade of the concentrates tended to decline. Gold grade of the concentrate was significantly increased by reloading of the coal oil agglomerates; on the other hand, substantial decreases were observed in total gold recovery after each successive cycle.     

An electrochemical study of gold cementation with zinc powder at low cyanide concentration in alkaline solutions

The half-reactions involved in gold cementation on zinc powder from low concentration alkaline cyanide solutions were studied in a steady state regime, employing electrodes of glassy carbon and graphite paste with zinc powder. The effects of pH, cyanide and initial gold concentrations were investigated using various electrochemical techniques. The results were used to determine the controlling step of the cementation at low cyanide concentration and to interpret the influence of the variables on this process. Mixed potentials and associated currents were determined from the Evans' diagrams constructed using sampled current–potentials curves from chronoamperometric results for half redox reactions. These values do not adequately describe the global cementation reaction because gold reduction in low cyanide concentration solutions is greatly influenced by a strong contribution from adsorptive processes. This behaviour is different from that found by other authors for concentrated gold and cyanide solutions, where the process is controlled by the complex ion diffusion (Au(CN)₂ ^–). The strong component of adsorption found in the present work does not permit the determination, using the Evans' diagrams, of the cementation velocity. Direct monitoring of the mixed potential was proposed, employing an electrode made of zinc powder in carbon paste submerged in a gold cyanide solution. The results of these experiments at low cyanide concentrations show that zinc oxidation is controlled by the formation of different passivating layers, the nature of which depended on the pH of the solution, and that the gold reduction reaction is strongly influenced by adsorption phenomena.