用纯橄岩制备硫酸镁的工艺研究

介绍了以纯橄岩为原料,采用酸浸法制备七水硫酸镁的工艺方法.研究并讨论了硫酸浓度、酸浸温度、酸浸时间、矿粉粒度、搅拌速度等因素对纯橄岩分解和七水硫酸镁制备的影响.具体制备方法及工艺条件:将纯橄岩在700 ℃煅烧4 h,用4 mol/L的硫酸溶液于100 ℃处理2 h,过滤,滤液经双氧水氧化,用氨水调pH=7.0～8.0,过滤除杂得到滤液,滤液经冷却结晶,在40～45 ℃烘干2 h后得粗硫酸镁晶体;粗硫酸镁晶体经重结晶,得高纯七水硫酸镁晶体.在此工艺条件下镁的浸出率可达97.86%,产品纯度为99.1%.产品符合HG/T 2680-1995工业七水硫酸镁的要求.     

纯橄岩酸碱离解法制备白炭黑的工艺比较

分别采用了酸碱离解2种方法从纯橄岩制备白炭黑,其中碱离解的实验条件为4 mol/LNaOH,100℃下,离解4 h,SiO2的浸出率36.55%;酸离解法的实验条件为4 mol/L H2SO4,90℃下,离解2 h,SiO2的浸出率为86.25%。酸离解法制备的白炭黑经测定纯度为96.28%;经FT-IR检测白炭黑的化学结构为水合二氧化硅;TEM图像显示白炭黑的形貌近似球状粒子,平均粒径50 nm以下。白炭黑pH值6.0-7.0,加热减量5.92%,1000℃灼烧减量为6.12%,产品符合中国行业标准HG/T3061-1999的要求。     

双腔防火防爆橡胶软管的研制

根据用途和安装部位的不同，纯胶管的结构形式也多种多样。纯胶管主要有两种用途：一种是输送水、油、乳化液和空气等各种流体介质；另一种是起防护作用的套管。本工作研制化学原料仓库低压线缆用防护套管。     

钢绳锚索在国外地下矿山的应用实例

┏━━━━━━━━┳━━━━━━━━┳━━━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━━━┳━━━━━━━┓┃ 矿山名称 ┃矿床及矿岩特征 ┃ 采矿方法及锚索用途 ┃ 锚索规格及有关参数 ┃ 实际效果 ┃┣━━━━━━━━╋━━━━━━━━╋━     

电子工业用高纯过氧化氢的开发

介绍电子工业用高纯过氧化氢产品种类与用途，生产与市场概况及制取方法。     

硅酸盐矿物的酸不溶物无定性SiO_2

本文通过从绿豆岩、蛇纹石酸解提取钾、铝和镁后所得到的酸不溶物无定性ＳｉＯ２，利用其特有的物理、化学性质、探索其多种用途。经初步研究认为，所得无定性ＳｉＯ２为一种具有广泛用途的新型基础无机材料。     

加快我省膨润土矿的开发利用

本文介绍了膨润土的性质和用途,分析了膨润土的省内资源概况和市场情况,提出了开发利用膨润土的建议。一、前言膨润土又名膨土岩、斑脱岩。它是以蒙脱石为主要矿物的粘土岩。除蒙脱石外还常含有其他矿物,如:粘土矿物伊利石、绿泥石、高岭土、水铝英石等;非粘土矿物沸石     

林德曼—西蒙森液固系反应模式在无机盐工业中的应用

本文认为该模式的用途有:(1)可用于无机盐新工艺的开发;(2)可用于无机盐生产上作为控制检验,(3)可利用此模式研究纯溶液与纯固相反应,然后同工业上含杂质     

优级纯氯化钠的生产工艺

优级纯氯化钠的生产工艺贾荣宝＊王本义（合肥工业大学化学试剂厂，合肥２３０００９）优级纯氯化钠的用途很广，主要用于微量测定氟和硅酸盐、生物培养基的制备、医药等。以工业氯化钠为原料，生产优级纯氯化钠，由于技术指标项目多，要求严格，给生产带来了一定的难度。...     

MDI的分类介绍

简要地介绍了纯MDI、粗MDI和液化MDI的规格和性能．并举例比较了一些典型用途及其净化处理方法。     

木质素/热塑性塑料复合材料界面增容的研究进展

将木质素作为一种有机颗粒填料添加到热塑性塑料中,可解决造纸黑液资源化利用、石油原料日渐紧张以及环境污染加剧等严峻问题。而木质素与热塑性塑料之间相容性直接影响木质素在塑料工业中的应用与发展。首先简要概述了木质素结构与性质和木质素/热塑性塑料复合材料的性能分析,然后系统地阐述国内外研究木质素/热塑性塑料复合材料界面增容方法及其原理;增容方法按添加相容剂、改性木质素和改性塑料进行归类,并对3种增容方法进行比较分析;接着综述了木质素复合材料中增容方法的交叉复合使用;最后对未来木质素/热塑性塑料复合材料界面增容的研究方向以及思路进行了展望。     

Pd-Pb/SiO2催化高浓度乙烯基乙炔加氢合成丁二烯

研究了硅胶负载钯铅双金属催化剂催化高浓度乙烯基乙炔加氢合成丁二烯过程。结果表明,加入适量的铅可起到分隔钯纳米粒子,阻碍钯纳米粒子团聚的作用,从而提高催化剂的催化活性,最佳Pb/Pd摩尔比为0.2。继续提高Pb/Pd摩尔比时,会生成铅钯合金相,造成催化剂活性降低。X射线光电子能谱结果表明,催化剂的催化活性与Pd 3d的电子结合能呈正相关关系。制备催化剂过程中,还原温度对催化剂的结构和催化性能影响显著。在350℃下还原得到的催化剂中金属氧化物还原不彻底,催化剂活性较低;还原温度为450℃时,则会引起钯纳米粒子烧结,造成催化剂的催化活性和对丁二烯的选择性同时降低;催化剂的最佳还原温度为400℃。在40℃催化乙烯基乙炔反应40 h后,积炭造成催化剂的孔道堵塞,催化剂失活。因此,需要进一步开展改善催化剂的抗积炭能力和使用寿命方面的研究。     

Natural products phytotoxicity A bioassay suitable for small quantities of slightly water-soluble compounds

A large variety of secondary metabolites that can inhibit germination and/or seedling growth are produced by plants in low quantities. The objective of this study was to develop a bioassay capable of reliably assessing reductions in germination percentage and seedling length of small-seeded plant species caused by exposure to minute quantities of these compounds. The germination and growth of alfalfa (Medicago saliva), annual ryegrass (Lolium multiflorum), and velvetleaf (Abutilon theophrasti) were evaluated against six known phytotoxins from five chemical classes; cinmethylin (a herbicidal cineole derivative) was selected as a comparison standard. Each phytotoxin, dissolved in a suitable organic solvent, was placed on water-agar in small tissue culture wells. After the solvent evaporated, imbibed seeds were placed on the agar; after three days, germination percentages and seedling lengths were measured. Compared to a commonly used filter paper procedure, this modified agar bioassay required smaller quantities of compound per seed for comparable bioassay results. This bioassay also readily permitted the measurement of seedling length, a more sensitive indicator of phytotoxicity than germination. Seedling length decreased sigmoidally as the toxin concentration increased logarithmically. Phytotoxicity was a function of both compound and plant species. Cinmethylin, a grass herbicide, reduced the length of annual ryegrass seedlings by 90–100%, whereas that of alfalfa and velvetleaf was inhibited slightly. The agar bioassay facilitated the rapid and reliable testing of slightly water-soluble compounds, requiring only minute quantities of each compound to give reproducible results.The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned.     

合成气经二甲醚羰基化及乙酸甲酯加氢制无水乙醇的研究进展

合成气经二甲醚羰基化及乙酸甲酯加氢路线制无水乙醇技术因具有诸多优点而备受市场关注。本文综述了该工艺的核心反应机理和最近研究进展。主要探讨了丝光沸石8元环与12元环对羰基化反应的作用。阐明了如何通过调变丝光沸石8元环与12元环的活性位来提高羰基化催化剂的活性与稳定性。评述了铜纳米粒子的粒径、分散度以及Cu⁺与Cu⁰的分布等特点对铜基催化剂加氢催化活性的影响。提高乙醇选择性与催化剂稳定性是该研究的重点与难点。指出羰基化催化剂的优化重点是调变丝光沸石的孔道结构,加氢催化剂的发展方向是构建高分散度的铜纳米粒子,并在反应过程中保持稳定。     

Kondensation von Dampfgemischen nicht mischbarer Flüssigkeiten

Condensation of Vapour Mixtures of Immiscible Liquids In contrast to the condensation of pure vapours and vapour mixtures of miscible liquids, the condensation of vapour mixtures forming immiscible or only partly miscible condensates is still poorly understood. Models describing heat transfer in the latter kind of condensation deviate so much from one another, not only quantitatively but also qualitatively, that reliable design of condensers is impossible. The reason lies primarily in the variety of flow patterns of two‐phase condensates, which range from pure droplet to pure film condensation. This paper surveys literature reports of the flow patterns and heat transfer occurring during condensation of vapour mixtures in the miscibility gap of their liquids. Qualitative knowledge in this condensation area is shown to be satisfactory. Several models have been proposed for heat transfer. However, the heat transfer coefficients obtained from these models differ too much from one another to allow one to choose the “best” correlation. Our own experiments with a eutectic benzene–water mixture on a vertical tube show that the calculation scheme proposed by Hoon and Burnside leads to acceptable results.     

Effect of structural characteristics on impact breakage of agglomerates

The mechanical properties and evolved structure of agglomerates depend strongly on the manufacturing method. There is a great interest in finding a simple way of establishing a rank order in their processing behaviour, e.g., the ease with which they could be dispersed in fluids. For this reason, the breakage propensity of two types of detergent agglomerates produced by different processes but with the same formulation has been evaluated under different conditions by impact testing with a view to diagnose differences in mechanical properties and structure arising from their manufacturing method. The effects of impact velocity, agglomerate size, impact angle, fatigue, humidity, and temperature have been analysed. Both samples show extensive plastic deformation due to the elongation and eventual rupture of the interparticle bridges, especially for the humidified samples. Reducing the temperature increases the extent of breakage substantially. The impact test results of samples kept at −20 °C show brittle failure mode, whilst those of oblique impacts at 45° and ambient conditions show a semi-brittle failure mode by shear deformation. Drying strengthens the agglomerates presumably due to the solidification of bridges. In contrast, humidifying the granules decreases their strength. A general comparison of the impact test results of both samples for different feed sizes shows that, due to the structural differences, the breakage trend of these two types of agglomerate varies with increasing agglomerate size.     

Effectiveness of Phlegmatizers in Explosive Compositions under Mechanical Loading

The mechanism of the effect of phlegmatizers in phlegmatized nitramines under mechanical loading is studied. Current concepts regarding the effect of phlegmatizers on the sensitivity of energetic materials to impact, friction, and vibration are considered; insufficiency of experimental data of this effect is noted. Experimental estimates of the phlegmatizing effect of various phlegmatizers on HMX are given. __________ Translated from Fizika Goreniya i Vzryva, Vol. 42, No. 1, pp. 100–105, January–February, 2006.     

Formation of metal oxide nanoparticles in combustion of titanium and aluminum droplets

A study was performed of the formation of metal oxide nanoparticles during combustion of aluminum and titanium drops which moved in air at a velocity of up to 3 m/sec. The source of the burning particles was a pyrotechnic mixture which contained an oxidizer, a binder, and metal particles of size 4–350 μm. Transmission electron microscopic studies showed that the combustion products were 1–10 μm aggregates of fractal structure consisting of primary particles (spherules) of Al₂O₃/TiO₂ 5–150 nm in diameter. The Brownian diffusion of the aggregates and their motion in electric and gravitational fields were observed using videomicroscopic recording. The charge distribution of TiO₂ aggregates and the equivalent radius of Brownian mobility were determined. In Al combustion, the zone of nanoparticle formation is separated from the particle surface by a distance approximately equal to the particle radius, and in Ti combustion, this zone is located directly near the surface. Coagulation of the oxide aerosol in the track of a burning particle leads to aerogelation with the formation of huge aggregates. Analytical expressions for approximate calculation of the parameters of the oxide particles and zones of their formation are proposed. __________ Translated from Fizika Goreniya i Vzryva, Vol. 42, No. 6, pp. 33–47, November–December, 2006.     

全氟聚醚聚合物及其功能复合材料的研究进展

全氟聚醚（PFPE）聚合物具有极低的表面张力、低摩擦系数、优异的润滑性能和良好的疏水疏油性能，被广泛用作航空航天、核工业、真空、电子等领域的润滑材料以及合成功能复合材料的反应中间体。近年来，基于PFPE聚合物的含氟功能复合材料在一些新兴领域受到广泛关注。本文首先介绍了PFPE聚合物在润滑材料领域最新的研究进展，重点阐述了目前PFPE润滑剂在抗磨、防锈和PFPE基础油抗爬移方面存在的不足，并分析了其原因；其次概述了PFPE聚合物在功能涂层、含氟聚氨酯材料、氟橡胶以及类玻璃（Vitrimers）材料方面的研究进展和应用前景，并介绍了一些含氟功能复合材料的制备工艺；最后展望了PFPE聚合物未来的研究重点和发展趋势，旨在为拓宽PFPE聚合物的应用领域，开发高附加值的PFPE衍生产品提供思路。     

提钒技术研究进展

综述了1980-2015年期间钒矿、含钒磷铁、废钒催化剂、钢渣和石煤等常见提钒原料之提钒技术的研究进展,对目前较具代表性的提钒工艺技术进行了较系统地分析总结,将这些提钒工艺技术归结为冶金工艺、焙烧工艺、湿法提钒、其他新型工艺四大类进行分类阐述;对各类提钒工艺技术进行了举例说明,对其基本过程进行了概述,并对其优缺点进行了较客观的分析和评述。在此基础上,发现和指出了长期以来我国提钒工艺过程中普遍存在的主要问题:首先,钒资源提钒的工艺技术水平仍然较低,废弃物较多,环境污染较严重;其次伴生矿或元素利用较低,钒资源综合利用程度较低。最后,指出了提钒技术的发展趋势:在强调环境保护的背景下,乞待开发新的环境污染较少、钒资源综合利用程度较高的提钒工艺。